LVGL Widgets

At the next level of the LVGL object hierarchy are the widgets, which support styling directly. They can have sub-parts, which may be styled separately. Usually styles are inherited, but this depends on widget specifics or functionality. The widget and its parts have states, and different styling can be set for different states.

Widgets can have children, which can be any other widgets. Think of this as a nested structure. The child widgets move with the parent and, if the parent is hidden, its children will also be hidden.

By default, LVGL draws new widgets on top of old widgets, including their children. When widgets have children, property inheritance takes place. Some properties (typically those related to text and opacity) can be inherited from the parent widgets’s styles. When the property is inheritable, the parent will be searched for an object which specifies a value for the property. The parents will use their own state to determine the value. For example, if a button is pressed and the text color is defined by the “pressed” state, this “pressed” text color will be used.

Common properties

The properties below are common to all widgets.

Configuration variables:

  • id (Optional, ID): Manually specify the ID used for code generation.

  • x (Optional, int16 or percentage): Horizontal position of the widget.

  • y (Optional, int16 or percentage): Vertical position of the widget.

Note

By default, the x and y coordinates are measured from the top left corner of the parent’s content area. Important: content area starts after the padding thus if the parent has a non-zero padding value, position will be shifted with that. Percentage values are calculated from the parent’s content area size.

If specifying align, x and y can be used as an offset to the calculated position (can also be negative). They are ignored if Layouts are used on the parent.

  • height (Optional): Height of the widget in pixels or a percentage, or SIZE_CONTENT.

  • width (Optional): Width of the widget in pixels or a percentage, or SIZE_CONTENT.

Note

The size settings support a special value: SIZE_CONTENT. It means the widget’s size in the respective direction will be set to the size of its children. Note that only children on the right and bottom sides will be considered and children on the top and left remain cropped. This limitation makes the behavior more predictable. Widgets with hidden or floating flags will be ignored by the SIZE_CONTENT calculation.

Similarly to CSS, LVGL also supports min_width, max_width, min_height and max_height. These are limits preventing a widget’s size from becoming smaller/larger than these values. They are especially useful if the size is set by percentage or SIZE_CONTENT.

  • min_width, max_width, min_height, max_height (Optional, int16 or percentage): Sets a minimal/maximal width or a minimal/maximal height. Pixel and percentage values can be used. Percentage values are relative to the dimensions of the parent’s content area. Defaults to 0%.

  • scrollbar_mode (Optional, string): If a child widget is outside its parent content area (the size without padding), the parent can become scrollable (see the scrollable flag). The widget can either be scrolled horizontally or vertically in one stroke. Scroll bars can appear depending on the setting:
    • "OFF": Never show the scroll bars (use the double quotes!).

    • "ON": Always show the scroll bars (use the double quotes!).

    • "ACTIVE": Show scroll bars while a widget is being scrolled.

    • "AUTO": Show scroll bars when the content is large enough to be scrolled (default).

  • align (Optional, enum): Alignment of the of the widget relative to the parent. A child widget is clipped to its parent boundaries. One of the values not starting with OUT_ (see picture below).

  • align_to (Optional, list): Alignment of the of the widget relative to another widget on the same level:
    • id (Required): The ID of a widget to which you want to align.

    • align (Required, string): Desired alignment (one of the values starting with OUT_).

    • x (Optional, int16 or percentage): Horizontal offset position. Default 0.

    • y (Optional, int16 or percentage): Vertical offset position. Default 0.

../../_images/lvgl_align.png
  • group (Optional, string): The name of the group of widgets which will interact with a Rotary Encoder Sensor. In every group there is always one focused widget which receives the encoder actions. You need to associate an input device with a group. An input device can send key events to only one group but a group can receive data from more than one input device. If no group is specified for a widget or an encoder, an unnamed default group will be assigned, so in most cases where only one encoder is used it will not be necessary to explicitly specify a group.

  • layout (Optional): See Layouts for details. Defaults to NONE.

  • styles (Optional, ID): The ID of a style definition from the main component configuration to override the theme styles.

  • theme (Optional, list): A list of styles to apply to the widget and children. Same configuration option as at the main component.

  • widgets (Optional, list): A list of LVGL widgets to be drawn as children of this widget. Same configuration option as at the main component.

  • state (Optional, dict): Widgets or their (sub)parts can have have states, which support separate styling. These state styles inherit from the theme, but can be locally set or overridden within style definitions. Can be one of:
    • checked (Optional, boolean): Toggled or checked state.

    • default (Optional, boolean): Normal, released state.

    • disabled (Optional, boolean): Disabled state (also usable with shorthand actions lvgl.widget.enable and lvgl.widget.disable).

    • edited (Optional, boolean): Edit by an encoder.

    • focus_key (Optional, boolean): Focused via keypad or encoder but not via touch screen.

    • focused (Optional, boolean): Focused via keypad or encoder or clicked via touch screen.

    • pressed (Optional, boolean): Being pressed.

    • scrolled (Optional, boolean): Being scrolled.

    • user_1, user_2, user_3, user_4 (Optional, boolean): Custom states.

By default, states are all false, and they are templatable. To apply styles to the states, you need to specify them one level above, for example:

- button:
    checkable: true
    state:
      checked: true # here you activate the state to be used at boot
    checked:
      bg_color: 0x00FF00 # here you apply styles to be used when in the respective state

The state itself can be can be changed by interacting with the widget, or through actions with lvgl.widget.update.

See Cover status and control for a cookbook example which demonstrates how to use styling and properties to show different states of a Home Assistant entity.

In addition to visual styling, each widget supports some boolean flags to influence the behavior:

  • adv_hittest (Optional, boolean): allow performing more accurate hit (click) test. For example, may help by accounting for rounded corners.

  • checkable (Optional, boolean): toggle checked state when the widget is clicked.

  • click_focusable (Optional, boolean): add focused state to the widget when clicked.

  • clickable (Optional, boolean): make the widget clickable by input devices. Defaults to true. If false, it will pass the click to the widgets behind it (clicking through).

  • event_bubble (Optional, boolean): propagate the events to the parent.

  • floating (Optional, boolean): do not scroll the widget when the parent scrolls and ignore layout.

  • gesture_bubble (Optional, boolean): propagate the gestures to the parent.

  • hidden (Optional, boolean): make the widget hidden (like it wasn’t there at all), also usable with shorthand actions lvgl.widget.show and lvgl.widget.hide. Hidden objects are ignored in layout calculations. Defaults to false.

  • ignore_layout (Optional, boolean): the widget is simply ignored by the layouts. Its coordinates can be set as usual.

  • layout_1, layout_2 (Optional, boolean): custom flags, free to use by layouts.

  • overflow_visible (Optional, boolean): do not clip the children’s content to the parent’s boundary.

  • press_lock (Optional, boolean): keep the widget pressed even if the press slid from the widget.

  • scroll_chain simple (Optional, boolean): packaging for (scroll_chain_hor | scroll_chain_ver).

  • scroll_chain_hor (Optional, boolean): allow propagating the horizontal scroll to a parent.

  • scroll_chain_ver (Optional, boolean): allow propagating the vertical scroll to a parent.

  • scroll_elastic (Optional, boolean): allow scrolling inside but with slower speed.

  • scroll_momentum (Optional, boolean): make the widget scroll further when “thrown”.

  • scroll_on_focus (Optional, boolean): automatically scroll widget to make it visible when focused.

  • scroll_one (Optional, boolean): allow scrolling only on snappable children.

  • scroll_with_arrow (Optional, boolean): allow scrolling the focused widget with arrow keys.

  • scrollable (Optional, boolean): the widget can become scrollable. Defaults to true (also see the scrollbar_mode property).

  • snappable (Optional, boolean): if scroll snap is enabled on the parent it can snap to this widget.

  • user_1, user_2, user_3, user_4 (Optional, boolean): custom flags, free to use by user.

  • widget_1, widget_2 (Optional, boolean): custom flags, free to use by widget.

Note

LVGL only supports integers for numeric value. Visualizer widgets can’t display floats directly, but they allow scaling by 10s. Some examples in the Cookbook cover how to do that.

Widget parts

Widgets can have multiple parts, each of which can be styled independently. For example, a checkbox has a main part that styles the background and text label, and an indicator part that styles the tick box. All widgets have a main part, the available parts for other widgets are specified in the widget description.

The possible parts are:

  • main (Optional, dict): The main part of the widget, i.e. the background. Any style properties applied at the top level of the widget are assumed to apply to this part, but may also be specified under the main config key.

  • scrollbar (Optional, dict): The scrollbar styles.

  • indicator (Optional, dict): The indicator part of the widget. The indicator part may be used to show tick boxes or other visual indicators in slider, bar or arc.

  • knob (Optional, dict): The knob part of the widget e.g. a draggable item in slider, bar or arc.

  • selected (Optional, dict): The currently selected part of the widget, e.g. text or the selected item in a roller.

  • items (Optional, dict): The items part of the widget, e.g. the items in a roller.

  • ticks (Optional, dict): Ticks on scales for a meter.

  • cursor (Optional, dict): The cursor part of the widget, e.g. the cursor in a spinbox.

# Example slider with knob and indicator styling
- slider:
    # main (background) styles
    bg_opa: cover
    bg_grad: color_bar
    radius: 0
    indicator:
      bg_opa: transp    # Makes the indicator part invisible
    knob:
      radius: 1
      width: 4
      height: 10%
      bg_color: 0x000000

Widget-specific properties

Some widgets have properties that are specific to that widget. For example label has a text property. The properties specific to a widget are described in each section below. Some of these properties may also be updated with a corresponding lvgl.<widget_type>.update action, e.g. lvgl.label.update allows updating not only the common style properties, but also the text property of a label.

Text property

Several widgets have a text property, and the possible ways this can be specified are common to all text properties. The text may be a Unicode string or other constant convertible to a string; if the string is enclosed in double quotes "" then standard escape sequences sucn as newline \n and Unicode codepoints will be translated. The text value may also be a lambda returning a std::string or may be specified with a format property utilising printf style formatting. There is also a time_format option which allows use of strftime formats.

Examples:

# Example label
- label:
    id: label_id
    text: "Text string"
- checkbox:
    id: checkbox_id
    text: "\uF00C"  # Unicode check-mark


on_...:
  - lvgl.label.update:
      id: label_id
      text:
        format: "%d bells, %d things"
        args: [x, 10]  # x is a value from the enclosing trigger.
  - lvgl.label.update:
      id: label_id
      text: !lambda return id(text_sensor).state;
  - lvgl.label.update:
      id: label_id
      text:
        time_format: "%c"   # uses default time component
  - lvgl.checkbox.update:
      id: checkbox_id
      text:
        time_format: "%c"
        time: sntp_id
  - lvgl.label.update:
      id: label_id
      text:
        time_format: "%c"
        time: !lambda return id(sntp_id).utcnow();

animimg

The animation image is similar to the normal image widget. The main difference is that instead of one source image, you set a list of multiple source images. You can also specify a duration and a repeat count.

../../_images/lvgl_animimg.gif

Configuration variables:

  • src (Required, list of images): A list of IDs of existing image configurations to be loaded as frames of the animation.

  • auto_start (Optional, boolean): Start the animation playback automatically at boot and when updating the widget. Defaults to true.

  • duration (Required, Time): Total duration of a playback cycle (each frame is displayed for an equal amount of time).

  • repeat_count (Optional, int16 or forever): The number of times playback should be repeated. Defaults to forever.

  • Some style options from Style properties for the background rectangle that uses the typical background style properties and the image itself using the image style properties.

Actions:

  • lvgl.animimg.start action starts the animation playback if it was displayed with auto_start false or after repeat_count expired.
    • id (Required): The ID or a list of IDs of animimg widgets which you want start.

  • lvgl.animimg.stop action stops the animation playback.
    • id (Required): The ID or a list of IDs of animimg widgets which you want stop.

  • lvgl.animimg.update action can be used to change repeat_count and duration, just like the lvgl.widget.update action is used for the common styles, states or flags. src and auto_start cannot be updated at runtime.
    • id (Required): The ID or a list of IDs of animimg widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- animimg:
    align: CENTER
    id: anim_id
    src: [ cat_image, cat_image_bowtie ]
    duration: 1000ms

# Example actions:
on_...:
  then:
    - lvgl.animimg.update:
        id: anim_id
        repeat_count: 100
        duration: 300ms

See Battery charging animation in the Cookbook for a more detailed example.

arc

The arc consists of a background and a foreground arc. The indicator foreground can be touch-adjusted with a knob.

../../_images/lvgl_arc.png

Configuration variables:

  • adjustable (Optional, boolean): Add a knob that the user can move to change the value. Defaults to false.

  • arc_color (Optional, color): Color used to draw the arc.

  • arc_opa (Optional, opacity): Opacity of the arc.

  • arc_rounded (Optional, boolean): Make the end points of the arcs rounded. true rounded, false perpendicular line ending.

  • arc_width (Optional, int16): Set the width of the arcs in pixels.

  • change_rate (Optional, int8): If the arc is pressed the current value will set with a limited speed according to the set change rate. The change rate is defined in degree/second. Defaults to 720.

  • end_angle (Optional, 0-360): end angle of the arc background (see note). Defaults to 45.

  • indicator (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize. Draws another arc using the arc style properties. Its padding values are interpreted relative to the background arc.

  • knob (Optional, list): Settings for the knob part to control the value. Supports a list of styles and state-based styles to customize. Draws a handle on the end of the indicator using all background properties and padding values. With zero padding the knob size is the same as the indicator’s width. Larger padding makes it larger, smaller padding makes it smaller.

  • max_value (Optional, int8): Maximum value of the indicator. Defaults to 100.

  • min_value (Optional, int8): Minimum value of the indicator. Defaults to 0.

  • mode (Optional, string): NORMAL: the indicator is drawn from the minimum value to the current. REVERSE: the indicator is drawn counter-clockwise from the maximum value to the current. SYMMETRICAL: the indicator is drawn from the middle point to the current value. Defaults to NORMAL.

  • rotation (Optional, 0-360): Offset to the 0 degree position. Defaults to 0.0.

  • start_angle (Optional, 0-360): start angle of the arc background (see note). Defaults to 135.

  • value (Required, int8): Actual value of the indicator at start, in 0-100 range. Defaults to 0.

  • Any Styling and state-based option to override styles inherited from parent. The arc’s size and position will respect the padding style properties.

If the adv_hittest flag is enabled the arc can be clicked through in the middle. Clicks are recognized only on the ring of the background arc.

Note

The zero degree position is at the middle right (3 o’clock) of the widget and the degrees increase in a clockwise direction from there. Angles are specified in the 0-360 range.

Actions:

  • lvgl.arc.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of arc widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

  • on_value trigger is activated when the knob changes the value of the arc. The new value is returned in the variable x.

  • interaction LVGL event triggers which also return the value in x.

Example:

# Example widget:
- arc:
    x: 10
    y: 10
    id: arc_id
    value: 75
    min_value: 0
    max_value: 100
    adjustable: true

# Example action:
on_...:
  then:
    - lvgl.arc.update:
        id: arc_id
        knob:
          bg_color: 0x00FF00
        value: 55

# Example trigger:
- arc:
    ...
    on_value:
      - logger.log:
          format: "Arc value is: %.0f"
          args: [ 'x' ]

Note

The on_value trigger is sent as the arc knob is dragged or changed with keys. The event is sent continuously while the arc knob is being dragged; this generally has a negative effect on performance. To mitigate this, consider using a universal interaction trigger like on_release, to get the x variable once after the interaction has completed.

The arc can be also integrated as a Number or Sensor component.

See Light brightness slider and Media player volume slider for examples which demonstrate how to use a slider (or an arc) to control entities in Home Assistant.

bar

The bar widget has a background and an indicator foreground on it. The size of the indicator is set according to the current value of the bar.

../../_images/lvgl_bar.png

Vertical bars can be created if the width is smaller than the height.

Not only the end, but also the start value of the bar can be set, which changes the start position of the indicator.

Configuration variables:

  • anim_time (Optional, Time): Sets the animation time if the value is set with animated: true.

  • animated (Optional, boolean): Animate the indicator when the bar changes value. Defaults to true.

  • indicator (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize, all the typical background properties.

  • max_value (Optional, int8): Maximum value of the indicator. Defaults to 100.

  • min_value (Optional, int8): Minimum value of the indicator. Defaults to 0.

  • mode (Optional, string): NORMAL: the indicator is drawn from the minimum value to the current. REVERSE: the indicator is drawn counter-clockwise from the maximum value to the current. SYMMETRICAL: the indicator is drawn from the middle point to the current value. Defaults to NORMAL.

  • value (Required, int8): Actual value of the indicator at start, in 0-100 range. Defaults to 0.

  • Style options from Style properties. The background of the bar and it uses the typical background style properties. Adding padding will make the indicator smaller or larger.

Actions:

  • lvgl.bar.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of bar widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- bar:
    x: 10
    y: 100
    id: bar_id
    value: 75
    min_value: 1
    max_value: 100

# Example action:
on_...:
  then:
    - lvgl.bar.update:
        id: bar_id
        value: 55

The bar can be also integrated as Number or Sensor component.

button

Simple push (momentary) or toggle (two-states) button.

../../_images/lvgl_button.png

Configuration variables:

  • checkable (Optional, boolean): A significant flag to make a toggle button (which remains pressed in checked state). Defaults to false.

  • Style options from Style properties for the background of the button. Uses the typical background style properties.

A notable state is checked (boolean) which can have different styles applied.

Triggers:

  • on_value trigger is activated after clicking. If checkable is true, the boolean variable x, representing the checked state, may be used by lambdas within this trigger.

  • interaction LVGL event triggers.

Example:

# Example widget:
- button:
    x: 10
    y: 10
    width: 50
    height: 30
    id: btn_id

To have a button with a text label on it, add a child label widget to it:

# Example toggle button with text:
- button:
    x: 10
    y: 10
    width: 70
    height: 30
    id: btn_id
    checkable: true
    widgets:
      - label:
          align: center
          text: "Light"

# Example trigger:
- button:
    ...
    on_value:
      then:
        - logger.log:
            format: "Button checked state: %d"
            args: [ x ]

The button can be also integrated as a Binary Sensor or as a Switch component.

See Remote light button for an example which demonstrates how to use a checkable button to act on a Home Assistant service.

buttonmatrix

The button matrix widget is a lightweight way to display multiple buttons in rows and columns. It’s lightweight because the buttons are not actually created but instead simply drawn on the fly. This reduces the memory footprint of each button from approximately 200 bytes (for both the button and its label widget) down to only eight bytes.

../../_images/lvgl_buttonmatrix.png

Configuration variables:

  • rows (Required, list): A list for the button rows:
    • buttons (Required, list): A list of buttons in a row:
      • id (Optional): An ID for the button in the matrix.

      • key_code (Optional, string): One character be sent as the key code to a Key collector component instead of text when the button is pressed.

      • selected (Optional, boolean): Set the button as the most recently released or focused. Defaults to false.

      • text (Optional, Text property): Text to display on the button.

      • width (Optional): Width relative to the other buttons in the same row. Must be a value between 1 and 15; the default is 1 (for example, given a line with two buttons, one with width: 1 and another one with width: 2, the first will be 33% wide while the second will be 66% wide).

      • control (Optional): Binary flags to control behavior of the buttons (all false by default):
        • checkable (Optional, boolean): Enable toggling of a button, checked state will be added/removed as the button is clicked.

        • checked (Optional, boolean): Make the button checked. Apply checked styles to the button.

        • click_trig (Optional, boolean): Control how to trigger on_value : if true on click, if false on press.

        • custom_1 and custom_2 (Optional, boolean): Custom, free to use flags.

        • disabled (Optional, boolean): Apply disabled styles to the button.

        • hidden (Optional, boolean): Make a button hidden (hidden buttons still take up space in the layout, they are just not visible or clickable).

        • no_repeat (Optional, boolean): Disable repeating when the button is long pressed.

        • popover (Optional, boolean): Show the button label in a popover when pressing this button.

        • recolor (Optional, boolean): Enable recoloring of button text with #. For example: It's #FF0000 red#

  • items (Optional, list): Settings for the items part, the buttons all use the text and typical background style properties except translations and transformations.

  • one_checked (Optional, boolean): Allow only one button to be checked at a time (aka. radio buttons). Defaults to false.

  • Style options from Style properties for the background of the button matrix, uses the typical background style properties. pad_row and pad_column set the space between the buttons.

Actions:

  • lvgl.buttonmatrix.update action updates the item styles and properties specified in the specific state, items options.
    • id (Required): The ID or a list of IDs of buttonmatrix widgets which you want update.

    • Widget styles or properties from state, items options above, which you want update.

  • lvgl.matrix.button.update action updates the button styles and properties specified in the specific control, width and selected options.
    • id (Required): The ID or a list of IDs of matrix buttons which you want update.

    • Widget styles or properties from control, width and selected options above, which you want update.

Triggers:

  • on_value and interaction triggers can be configured for each button, is activated after clicking. If checkable is true, the boolean variable x, representing the checked state, may be used by lambdas within this trigger.

  • The interaction LVGL event triggers can be configured for the main widget, they pass the ID of the pressed button (or null if nothing pressed) as variable x (a pointer to a uint16_t which holds the index number of the button).

Example:

# Example widget:
- buttonmatrix:
    x: 10
    y: 40
    width: 220
    items:
      pressed:
        bg_color: 0xFFFF00
    id: matrix_id
    rows:
      - buttons:
        - id: button_1
          text: "\uF04B"
          control:
            checkable: true
        - id: button_2
          text: "\uF04C"
          control:
            checkable: true
      - buttons:
        - id: button_3
          text: "A"
          control:
            popover: true
        - id: button_4
          text: "B"
          control:
            disabled: true
      - buttons:
        - id: button_5
          text: "It's #ff0000 red#"
          width: 2
          control:
            recolor: true

# Example action:
on_...:
  then:
    - lvgl.matrix.button.update:
        id: button_1
        width: 1
        selected: true
        control:
          checkable: false
    - lvgl.buttonmatrix.update:
        id: matrix_id
        state:
          disabled: true
        items:
          bg_color: 0xf0f0f0

# Example trigger:
- buttonmatrix:
    ...
    rows:
      - buttons:
        ...
        - id: button_2
          ...
          control:
            checkable: true
          on_value: # Trigger for the individual button, returning the checked state
            then:
              - logger.log:
                  format: "Button 2 checked: %d"
                  args: [ x ]
    on_press: # Triggers for the matrix, to determine which button was pressed.
      logger.log:
        format: "Matrix button pressed: %d"
        args: ["x"]  # If x is 65535, it was the container, (or through a disabled button).
    on_click:
      logger.log:
        format: "Matrix button clicked: %d, is button_2 = %u"
        args: ["x", "id(button_2) == x"]

Tip

The Button Matrix widget supports the Key collector component to collect the button presses as key press sequences for further automations. Check out A numeric input keypad for an example.

checkbox

The checkbox widget is made internally from a tick box and a label. When the checkbox is clicked the tick box’s checked state will be toggled.

../../_images/lvgl_checkbox.png

Configuration variables:

  • indicator (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize. The “tick box” is a square that uses all the typical background style properties. By default, its size is equal to the height of the main part’s font. Padding properties make the tick box larger in the respective directions.

  • Style options from Style properties for the background of the widget and it uses the text and all the typical background style properties. pad_column adjusts the spacing between the tick box and the label.

Actions:

  • lvgl.checkbox.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of checkbox widgets which you want update.

    • text (Optional, Text property): Text to display beside the checkbox.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

on_value trigger is activated when toggling the checkbox. The boolean variable x, representing the checkbox’s state, may be used by lambdas within this trigger. - interaction LVGL event triggers which also return the value in x.

Example:

# Example widget:
- checkbox:
    x: 10
    y: 10
    id: checkbox_id
    text: Checkbox

# Example action:
on_...:
  then:
    - lvgl.checkbox.update:
        id: checkbox_id
        state:
          checked: true
        text: Checked

# Example trigger:
- checkbox:
    ...
    on_value:
      then:
        - logger.log:
            format: "Checkbox state: %d"
            args: [ x ]

Note

In case you configure default_font in the main section to a custom font, the checkmark will not be shown correctly when the checkbox is in the checked state. See Restore checkbox mark for how to easily resolve this.

The checkbox can be also integrated as a Switch component.

image

Images are the basic widgets used to display images.

../../_images/lvgl_image.png

Configuration variables:

  • angle (Optional, 0-360): Rotation of the image. Defaults to 0.0. Needs pivot_x and pivot_y to be specified.

  • antialias (Optional): The quality of the angle or scale transformation. When anti-aliasing is enabled, the transformations are higher quality but slower. Defaults to false.

  • mode (Optional): Either REAL or VIRTUAL. With VIRTUAL, when the image is scaled or rotated, the real coordinates of the image object are not changed. The larger content simply overflows the object’s boundaries. It also means the layouts are not affected the by the transformations. With REAL, if the width/height of the object is set to SIZE_CONTENT, the object’s size will be set to the scaled and rotated size. If an explicit size is set, the overflowing content will be cropped. Defaults to VIRTUAL.

  • offset_x (Optional): Add a horrizontal offset to the image position.

  • offset_y (Optional): Add a vertical offset to the image position.

  • pivot_x (Optional): Horizontal position of the pivot point of rotation, in pixels, relative to the top left corner of the image.

  • pivot_y (Optional): Vertical position of the pivot point of rotation, in pixels, relative to the top left corner of the image.

  • zoom (Optional, 0.1-10): Zoom of the image.

  • src (Required, image): The ID of an existing image configuration.

  • Some style options from Style properties for the background rectangle that uses the typical background style properties and the image itself using the image style properties.

Actions:

  • lvgl.image.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags. Updating the src option changes the image at runtime.
    • id (Required): The ID or a list of IDs of image widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- image:
    align: CENTER
    src: cat_image
    id: img_id
    radius: 11
    clip_corner: true

# Example action:
on_...:
  then:
    - lvgl.image.update:
        id: img_id
        src: cat_image_bowtie

Note

Currently RGB565 type images are supported, with transparency using the optional parameter use_transparency set to true. See Images for how to load an image for rendering in ESPHome.

Tip

offset_x and offset_y can be useful when the widget size is set to be smaller than the image source size. A “running image” effect can be created by animating these values.

keyboard

The keyboard widget is a special Button matrix with predefined keymaps and other features to show an on-screen keyboard usable to type text into a textarea.

../../_images/lvgl_keyboard.png

For styling, the keyboard widget uses the same settings as buttonmatrix.

Configuration variables:

  • textarea (Optional): The ID of a textarea to associate with the keyboard. If provided, all key entries are recorded in the textarea.

  • mode (Optional, enum): Keyboard layout to use. Each TEXT_ layout contains a button to allow the user to iterate through the TEXT_ layouts.
    • TEXT_LOWER: Display lower case letters (default).

    • TEXT_UPPER: Display upper case letters.

    • TEXT_SPECIAL: Display special characters.

    • NUMBER: Display numbers, +/- sign, and decimal dot.

Actions:

  • lvgl.keyboard.update action updates the properties from the specific options above, plus any from lvgl.widget.update.
    • id (Required): The ID or a list of IDs of keyboard widgets which you want to update.

    • Styles or properties to be updated.

Triggers:

  • on_ready trigger is activated when the checkmark key is pressed.

  • on_cancel trigger is activated when the key containing the keyboard icon is pressed.

Example:

# Example widget:
- keyboard:
    id: keyboard_id
    textarea: textarea_1
    mode: TEXT_UPPER

# Example actions:
on_focus:
  then:
    - lvgl.keyboard.update:
        id: keyboard_id
        mode: number
        textarea: textarea_2

# Example trigger:
- keyboard:
    ...
    on_ready:
      then:
        - logger.log: Keyboard is ready
    on_cancel:
      then:
        - logger.log: Keyboard cancelled

Tip

The Keyboard widget supports the Key collector component to collect the button presses as key press sequences for further automations.

Note

The Keyboard widget in ESPHome doesn’t support popovers or custom layouts.

label

A label is the basic widget type that is used to display text.

../../_images/lvgl_label.png

Configuration variables:

  • long_mode (Optional, list): By default, the width and height of the label is set to SIZE_CONTENT. Therefore, the size of the label is automatically expanded to the text size. Otherwise, if the width or height are explicitly set (or set by Layouts), the lines wider than the label’s width can be manipulated according to the long mode policies below. These policies can be applied if the height of the text is greater than the height of the label.
    • WRAP: Wrap lines which are too long. If the height is SIZE_CONTENT, the label’s height will be expanded, otherwise the text will be clipped (default).

    • DOT: Replaces the last 3 characters from bottom right corner of the label with dots.

    • SCROLL: If the text is wider than the label, scroll the text horizontally back and forth. If it’s higher, scroll vertically. Text will scroll in only one direction; horizontal scrolling has higher precedence.

    • SCROLL_CIRCULAR: If the text is wider than the label, continuously scroll the text horizontally. If it’s higher, scroll vertically. Text will scroll in only one direction; horizontal scrolling has higher precedence.

    • CLIP: Simply clip the parts of the text outside the label.

  • recolor (Optional, boolean): Enable recoloring of button text with #. This makes it possible to set the color of characters in the text individually by prefixing the text to be re-colored with a #RRGGBB hexadecimal color code followed by a space, and finally closed with a single hash # tag. For example: Write a #FF0000 red# word.

  • scrollbar (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize. The scroll bar that is shown when the text is larger than the widget’s size.

  • selected (Optional, list): Settings for the the style of the selected text. Only text_color and bg_color style properties can be used.

  • text_align (Optional, enum): Alignment of the text in the widget - it doesn’t align the object itself, only the lines inside the object. One of LEFT, CENTER, RIGHT, AUTO. Inherited from parent. Defaults to AUTO, which detects the text base direction and uses left or right alignment accordingly.

  • text_color (Optional, color): Color to render the text in. Inherited from parent. Defaults to 0 (black).

  • text_decor (Optional, list): Choose decorations for the text: NONE, UNDERLINE, STRIKETHROUGH (multiple can be specified as YAML list). Inherited from parent. Defaults to NONE.

  • text_font: (Optional, font): The ID of the font used to render the text or symbol. Inherited from parent.

  • text_letter_space (Optional, int16): Extra character spacing of the text. Inherited from parent. Defaults to 0.

  • text_line_space (Optional, int16): Line spacing of the text. Inherited from parent. Defaults to 0.

  • text_opa (Optional, opacity): Opacity of the text. Inherited from parent. Defaults to COVER.

  • text (Optional, Text property): Text to display on the label.

  • Style options from Style properties. Uses all the typical background properties and the text properties. The padding values can be used to add space between the text and the background.

Note

Newline escape sequences are handled automatically by the label widget. You can use \n to make a line break. For example: "line1\nline2\n\nline4". For escape sequences like newline to be translated, enclose the string in double quotes.

Actions:

  • lvgl.label.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of label widgets which you want update.

    • text (Optional, Text property): Text to display on the button.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- label:
    align: CENTER
    id: lbl_id
    recolor: true
    text: "#FF0000 write# #00FF00 colored# #0000FF text#"

- label:
    align: TOP_MID
    id: lbl_symbol
    text_font: montserrat_28
    text: "\uF013"

# Example action (update label with a value from a sensor):
on_...:
  then:
    - lvgl.label.update:
        id: lbl_id
        text:
          format: "%.0fdBm"
          args: [ 'id(wifi_signal_db).get_state()' ]

The label can be also integrated as Text or Text Sensor component.

led

The LED widgets are either circular or rectangular widgets whose brightness can be adjusted. As their brightness decreases, the colors become darker.

../../_images/lvgl_led.png

Configuration variables:

  • brightness (Optional, percentage): The brightness of the LED color, where 0% corresponds to black, and 100% corresponds to the full brightness of the color specified above.

  • color (Optional, color): Color for the background, border, and shadow of the widget.

  • Style options from Style properties, using all the typical background style properties.

Actions:

  • lvgl.led.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of led widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- led:
    id: led_id
    align: CENTER
    color: 0xFF0000
    brightness: 70%

# Example action:
on_...:
  then:
    - lvgl.led.update:
        id: led_id
        color: 0x00FF00

The led can be also integrated as Light component.

Note

If configured as a light component, color and brightness are overridden by the light at startup, according to its restore_mode setting.

Check out A numeric input keypad in the Cookbook for an example which demonstrates how to change the led styling properties from an automation.

line

The line widget is capable of drawing straight lines between a set of points.

../../_images/lvgl_line.png

Configuration variables:

  • line_color (Optional, color): Color for the line.

  • line_dash_gap (Optional, int16): Set the width of the gap between the dashes in the line (in pixels).

  • line_dash_width (Optional, int16): Set the width of the dashes in the line (in pixels).

  • line_rounded (Optional, boolean): Make the end points of the line rounded. true rounded, false perpendicular line ending.

  • line_width (Optional, int16): Set the width of the line in pixels.

  • points (Required, list): A list of x, y integer pairs for point coordinates (origin from top left of parent)

  • Style options from Style properties, all the typical background properties and line style properties.

By default, the Line widget width and height dimensions are set to SIZE_CONTENT. This means it will automatically set its size to fit all the points. If the size is set explicitly, parts of the line may not be visible.

Example:

# Example widget:
- line:
    points:
      - 5, 5
      - 70, 70
      - 120, 10
      - 180, 60
      - 230, 15
    line_width: 8
    line_color: 0x0000FF
    line_rounded: true

meter

The meter widget can visualize data in very flexible ways. It can use arcs, needles, ticks, lines and/or labels.

../../_images/lvgl_meter.png

Configuration variables:

  • scales (Required, list): A list with (any number of) scales to be added to the meter.
    • angle_range (Required): The angle between start and end of the tick scale. Defaults to 270.

    • indicators (Required, list): A list with indicators to be added to the scale. Multiple of each can be added. Their values are interpreted in the range of the scale:
      • arc (Optional): Add a background arc the scale:
        • color: Color to draw the arc. Defaults to 0 (black).

        • end_value: The value in the scale range to end drawing the arc to.

        • r_mod: Adjust the position of the arc from the scale radius with this amount (can be negative). Defaults to 0.

        • start_value: The value in the scale range to start drawing the arc from.

        • width: Arc width in pixels. Defaults to 4.

        • opa: Opacity of the arc. Defaults to 100%.

      • image (Optional): Add a rotating needle image to the scale:
        • id: Manually specify the ID used for updating the indicator value at runtime.

        • pivot_x: Horizontal position of the pivot point of rotation, in pixels, relative to the top left corner of the image.

        • pivot_y: Vertical position of the pivot point of rotation, in pixels, relative to the top left corner of the image.

        • src: The ID of an existing image configuration, representing a needle pointing to the right like -o--->.

        • value: The value in the scale range to show at start.

        • opa: Opacity of the image. Defaults to 100%.

      • line (Optional): Add a needle line to the scale. By default, the length of the line is the same as the scale’s radius:
        • color: Color for the needle line. Defaults to 0 (black).

        • id: Manually specify the ID used for updating the indicator value at runtime.

        • r_mod: Adjust the length of the needle from the scale radius with this amount (can be negative). Defaults to 0.

        • value: The value in the scale range to show at start.

        • width: Needle line width in pixels. Defaults to 4.

        • opa: Opacity of the needle. Defaults to 100%.

      • tick_style (Optional): Add tick style modifications:
        • color_end: Color for the gradient end of the ticks.

        • color_start: Color for the gradient start of the ticks.

        • end_value: The value in the scale range to modify the ticks to.

        • local: If true the ticks’ color will be faded from color_start to color_end in the start and end values specified above. If false, color_start and color_end will be mapped to the entire scale range (and only a slice of that color gradient will be visible in the indicator’s start and end value range). Defaults to false.

        • start_value: The value in the scale range to modify the ticks from.

        • width: Modifies the width of the tick lines.

    • range_from (Required): The minimum value of the tick scale. Defaults to 0.

    • range_to (Required): The maximum value of the tick scale. Defaults to 100.

    • rotation (Optional): The rotation angle offset of the tick scale.

    • ticks (Required, list): A scale can have minor and major ticks and labels on the major ticks. To add the minor ticks:
      • color (Optional, color): Color to draw the ticks. Required if count is greater than 0. Defaults to 0x808080.

      • count (Required): How many ticks to be on the scale. Defaults to 12.

      • length (Optional): Tick line length in pixels. Required if count is greater than 0. Defaults to 10.

      • width (Optional): Tick line width in pixels. Required if count is greater than 0. Defaults to 2.

      • major (Optional, list): If you want major ticks and value labels displayed:
        • color: Color to draw the major ticks. Defaults to 0 (black).

        • label_gap: Label distance from the ticks with text proportional to the values of the tick line. Defaults to 4.

        • length: Tick line length in pixels or percentage. Defaults to 15%.

        • stride: How many minor ticks to skip when adding major ticks. Defaults to 3.

        • width: Tick line width in pixels. Defaults to 5.

      • Style options from Style properties for the tick lines and labels using the line and label text style properties.

  • Style options from Style properties for the background of the meter, using the typical background properties.

  • ticks (Optional, dict): Styling options for the ticks part, which will be applied to the tick lines and labels using standard line and label styles.

  • indicator (Optional, dict): Styling options for the indicator part, which will be applied to the needle line or image using standard line and image styles.

  • items (Optional, dict): Settings for the items part, which will be applied to arcs.

Note

The zero degree position is at the middle right (3 o’clock) of the widget and the degrees increase in a clockwise direction from there. Angles are specified in the 0-360 range.

Actions:

  • lvgl.indicator.update action updates indicator options as below. lvgl.widget.update action can be used for the common styles, states or flags of the meter widget.
    • id (Required): The ID or a list of IDs of indicators to update.

    • end_value (Optional): The value in the scale range to end drawing the arc to.

    • start_value (Optional): The value in the scale range to start drawing the arc from.

    • opa (Optional): Opacity of the indicator.

Triggers:

Example:

# Example widget:
- meter:
    align: center
    scales:
      range_from: -10
      range_to: 40
      angle_range: 240
      rotation: 150
      ticks:
        count: 51
        length: 3
        major:
          stride: 5
          length: 13
          label_gap: 13
      indicators:
        - line:
            id: temperature_needle
            width: 2
            color: 0xFF0000
            r_mod: -4
        - tick_style:
            start_value: -10
            end_value: 40
            color_start: 0x0000bd #FF0000
            color_end: 0xbd0000 #0000FF

# Example action:
on_...:
  then:
    - lvgl.indicator.update:
        id: temperature_needle
        value: 3

See Semicircle gauge, Thermometer and An analog clock in the Cookbook for examples which demonstrate how to effectively use this widget.

msgboxes

The message boxes act as pop-ups. They are built from a background container, a title, an optional close button, a text and optional buttons.

../../_images/lvgl_msgbox.png

The text will be broken into multiple lines automatically and the height will be set automatically to include the text and the buttons. The message box is modal (blocks clicks on the rest of the screen until closed).

Configuration variables:

  • msgboxes (Optional, list): A list of message boxes to use. This option is available only at the top level of the LVGL component configuration. Each list entry may have the following options:
    • title (Required, string): A string to display at the top of the message box.

    • body (Optional, dict): The content of the body of the message box:
      • text (Optional, Text property): The text to display in the body of the message box.

      • Style options from Style properties. Uses all the typical background properties and the text properties.

    • buttons (Optional, list): A list of buttons to show at the bottom of the message box:
    • button_style (Optional, dict): A style to apply to the buttons. Uses all the typical style properties. Buttons cannot be individually styled since they are part of a buttonmatrix.

    • close_button (Optional, boolean): Controls the presence of the close button to the top right of the message box. Defaults to true

Actions:

The configured message boxes are hidden by default. They can be shown and hidden using lvgl.widget.show and lvgl.widget.hide respectively actions.

Example:

# Example widget:
lvgl:
  ...
  msgboxes:
    - id: message_box
      close_button: true
      title: Message box
      body:
        text: "This is a sample message box."
        bg_color: 0x808080
      buttons:
        - id: msgbox_apply
          text: "Apply"
        - id: msgbox_close
          text: "\uF00D"
          on_click:
            then:
              - lvgl.widget.hide: message_box

Tip

You can create your own more complex dialogs with a full-screen sized, half-opaque obj with any child widgets on it, and the hidden flag set to true by default. For non-modal dialogs, simply set the clickable flag to false on it.

obj

The base object is just a simple, empty widget. By default, it’s nothing more than a rounded rectangle:

../../_images/lvgl_baseobj.png

You can use it as a parent container for other widgets. By default, it catches touches.

Configuration variables:

Triggers:

Example:

# Example widget:
- obj:
    x: 10
    y: 10
    width: 220
    height: 300
    widgets:
      - ...

roller

Roller allows you to simply select one option from a list by scrolling.

../../_images/lvgl_roller.png

Configuration variables:

  • anim_time (Optional, Time): When the Roller is scrolled and doesn’t stop exactly on an option it will scroll to the nearest valid option automatically in this amount of time.

  • mode (Optional, enum): Option to make the roller circular. NORMAL or INFINITE, defaults to NORMAL.

  • options (Required, list): The list of available options in the roller.

  • selected_index (Optional, int8): The index of the item you wish to be selected.

  • selected (Optional, list): Settings for the selected part to show the value. Supports a list of styles and state-based styles to customize. The selected option in the middle. Besides the typical background properties it uses the label text style properties to change the appearance of the text in the selected area.

  • visible_row_count (Optional, int8): The number of visible rows.

  • Style options from Style properties. The background of the roller uses all the typical background properties and label style properties. text_line_space adjusts the space between the options.

Actions:

  • lvgl.roller.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of roller widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

  • on_value trigger is activated when you select an item from the list. The new selected index is returned in the variable x.

  • interaction LVGL event triggers which also return the selected index in x.

Example:

# Example widget:
- roller:
    align: CENTER
    id: roller_id
    options:
      - Violin
      - Piano
      - Bassoon
      - Chello
      - Drums

# Example action:
on_...:
  then:
    - lvgl.roller.update:
        id: roller_id
        selected_index: 4

# Example trigger:
- roller:
    ...
    on_value:
      - logger.log:
          format: "Selected index is: %d"
          args: [ x ]

The roller can be also integrated as Select component.

slider

The slider widget looks like a bar supplemented with a knob. The user can drag the knob to set a value. Just like bar, slider can be vertical or horizontal. The size of the indicator foreground and the knob position is set according to the current value of the slider.

../../_images/lvgl_slider.png

Configuration variables:

  • anim_time (Optional, Time): Sets the animation time if the value is set with animated: true.

  • animated (Optional, boolean): Animate the indicator when the bar changes value. Defaults to true.

  • indicator (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize. The indicator shows the current state of the slider. Also uses all the typical background style properties.

  • knob (Optional, list): Settings for the knob part to control the value. Supports a list of styles and state-based styles to customize. A rectangle (or circle) is drawn at the current value. Also uses all the typical background properties to describe the knob. By default, the knob is square (with an optional corner radius) with side length equal to the smaller side of the slider. The knob can be made larger with the padding values. Padding values can be asymmetric.

  • max_value (Optional, int8): Maximum value of the indicator. Defaults to 100.

  • min_value (Optional, int8): Minimum value of the indicator. Defaults to 0.

  • value (Required, int8): Actual value of the indicator at start, in 0-100 range. Defaults to 0.

  • Any Styling and state-based option for the background of the slider. Uses all the typical background style properties. Padding makes the indicator smaller in the respective direction.

Normally, the slider can be adjusted either by dragging the knob, or by clicking on the slider bar. In the latter case the knob moves to the point clicked and slider value changes accordingly. In some cases it is desirable to set the slider to react on dragging the knob only. This feature is enabled by enabling the adv_hittest flag.

Actions:

  • lvgl.slider.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of slider widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

  • on_value trigger is activated when the knob changes the value of the slider. The new value is returned in the variable x.

  • interaction LVGL event triggers which also return the value in x.

Example:

# Example widget:
- slider:
    x: 10
    y: 10
    width: 220
    id: slider_id
    value: 75
    min_value: 0
    max_value: 100

# Example action:
on_...:
  then:
    - lvgl.slider.update:
        id: slider_id
        knob:
          bg_color: 0x00FF00
        value: 55

# Example trigger:
- slider:
    ...
    on_value:
      - logger.log:
          format: "Slider value is: %.0f"
          args: [ 'x' ]

Note

The on_value trigger is sent as the slider is dragged or changed with keys. The event is sent continuously while the slider is being dragged; this generally has a negative effect on performance. To mitigate this, consider using a universal interaction trigger like on_release, to get the x variable once after the interaction has completed.

The slider can be also integrated as Number or Sensor component.

See Light brightness slider and Media player volume slider for examples which demonstrate how to use a slider to control entities in Home Assistant.

spinbox

The spinbox contains a numeric value (as text) which can be increased or decreased through actions. You can, for example, use buttons labeled with plus and minus to call actions which increase or decrease the value as required.

../../_images/lvgl_spinbox.png

Configuration variables:

  • anim_time (Optional, Time): Sets the cursor’s blink time.

  • decimal_places (Optional, 0..6): The number of digits after the decimal point. If 0, no decimal point is displayed. Defaults to 0.

  • digits (Optional, 1..10): The number of digits (excluding the decimal separator and the sign characters). Defaults to 4.

  • range_from (Optional, float): The minimum value allowed to set the spinbox to. Defaults to 0.

  • range_to (Optional, float): The maximum value allowed to set the spinbox to. Defaults to 100.

  • rollover (Optional, boolean): While increasing or decreasing the value, if either the minimum or maximum value is reached with this option enabled, the value will change to the other limit. If disabled, the value will remain at the minimum or maximum value. Defaults to false.

  • step (Optional, float): The granularity with which the value can be set. Defaults to 1.0.

  • value (Required, float): Actual value to be shown by the spinbox at start.

Note

The sign character will only be shown if the set range contains negatives.

Actions:

  • lvgl.spinbox.update action updates the widget styles and properties from the specific options above, just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of spinbox widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

  • lvgl.spinbox.increment action increases the value by one step configured above.
    • id (Required): The ID of the spinbox widget which you want to increment.

  • lvgl.spinbox.decrement action decreases the value by one step configured above.
    • id (Required): The ID of the spinbox widget which you want to decrement.

Triggers:

  • on_value trigger is activated when the knob changes the value of the arc. The new value is returned in the variable x.

  • interaction LVGL event triggers which also return the value in x.

Example:

# Example widget:
- spinbox:
    id: spinbox_id
    text_align: center
    range_from: -10
    range_to: 40
    step: 0.5
    digits: 3
    decimal_places: 1

# Example actions:
on_...:
  then:
    - lvgl.spinbox.decrement: spinbox_id
on_...:
  then:
    - lvgl.spinbox.update:
        id: spinbox_id
        value: 25.5

# Example trigger:
- spinbox:
    ...
    on_value:
      then:
        - logger.log:
            format: "Spinbox value is %f"
            args: [ x ]

The spinbox can be also integrated as a Number or Sensor component.

See Climate control for an example which demonstrates how to implement a thermostat control using the spinbox.

spinner

The Spinner widget is a spinning arc over a ring.

../../_images/lvgl_spinner.gif

Configuration variables:

  • arc_color (Optional, color): Color to draw the arcs.

  • arc_length (Required, 0-360): Length of the spinning arc in degrees.

  • arc_opa (Optional, opacity): Opacity of the arc.

  • arc_rounded (Optional, boolean): Make the end points of the arcs rounded. true rounded, false perpendicular line ending.

  • arc_width (Optional, int16): Set the width of the arcs in pixels.

  • indicator (Optional, list): Settings for the indicator part to show the value. Supports a list of styles and state-based styles to customize. Draws another arc using the arc style properties. Its padding values are interpreted relative to the background arc.

  • spin_time (Required, Time): Duration of one cycle of the spin.

Actions:

  • lvgl.spinner.update action updates the widget styles and properties for the indicator part (anything other than the properties that apply commonly to all widgets), just like the lvgl.widget.update action is used for the common styles, states or flags.
    • id (Required): The ID or a list of IDs of spinner widgets which you want update.

    • Widget styles or properties from the specific options above, which you want update.

Triggers:

Example:

# Example widget:
- spinner:
    align: center
    spin_time: 2s
    arc_length: 60deg
    id: spinner_id
    indicator:
      arc_color: 0xd4d4d4

# Example action:
on_...:
  then:
    - lvgl.spinner.update:
        id: spinner_id
        arc_color: 0x31de70

switch

The switch looks like a little slider and can be used to turn something on and off.

../../_images/lvgl_switch.png

Configuration variables:

  • indicator (Optional, list): Settings for the indicator part, the foreground area underneath the knob shown when the switch is in checked state. Supports a list of styles and state-based styles to customize.

  • knob (Optional, list): Settings for the knob part to control the value. Supports a list of styles and state-based styles to customize.

  • Style options from Style properties.

Triggers:

  • on_value trigger is activated when toggling the switch. The boolean variable x, representing the switch’s state, may be used by lambdas within this trigger.

  • interaction LVGL event triggers which also return the value in x.

Example:

# Example widget:
- switch:
    x: 10
    y: 10
    id: switch_id

# Example trigger:
- switch:
    ...
    on_value:
      then:
        - logger.log:
            format: "Switch state: %d"
            args: [ x ]

The switch can be also integrated as a Switch component.

See Local light switch for an example which demonstrates how to use a switch to act on a local component.

tabview

The tab view object can be used to organize content in tabs. The tab buttons are internally generated with a buttonmatrix.

../../_images/lvgl_tabview.png

The tabs are indexed (zero-based) in the order they appear in the configuration file. A new tab can be selected either by clicking on a tab button, by sliding horizontally on the content or via the lvgl.tabview.select action, specifying the tab’s index.

Configuration variables:

  • position (Optional, enum): Position of the tab selector buttons. One of TOP, BOTTOM, LEFT, RIGHT. Defaults to TOP.

  • size (Optional, percentage): The height (in case of TOP, BOTTOM) or width (in case of LEFT, RIGHT) tab buttons. Defaults to 10%.

  • tabs (Required, list): A list with (any number of) tabs to be added to tabview.
    • name (Required): The text to be shown on the button corresponding to the tab.

    • id (Optional): An ID for the tab itself.

    • widgets (Required, list): A list of LVGL Widgets to be drawn on the tab, as children.

  • tab_style (Optional): Style settings for the tabs.
    • items (Optional, dict): Settings for the items part, the buttons all use the text and typical background style properties except translations and transformations.

Actions:

  • lvgl.tabview.select action jumps the view to the desired tab:
    • id (Required): The ID of the tabview which receives this action.

    • index (Required): The (zero-based) index of the tab to which to jump.

    • animated (Optional, boolean): To animate the movement. Defaults to false.

Triggers:

  • on_value trigger is activated when displayed tab changes. The new value is returned in the variable tab as the ID of the now-visible tab.

  • interaction LVGL event triggers.

Example:

# Example widget:
- tabview:
    id: tabview_id
    position: top
    tab_style:
      border_color: 0x00FF00
      border_width: 6
      items:
        text_color: 0x0000FF
    tabs:
      - name: Dog
        id: tabview_tab_1
        widgets:
          - image:
              src: dog_img
          ...
      ...

# Example action:
on_...:
  then:
    - lvgl.tabview.select:
        id: tabview_id
        index: 1
        animated: true

# Example trigger:
- tabview:
    ...
    on_value:
      then:
        - if:
            condition:
              lambda: return tab == id(tabview_tab_1);
            then:
              - logger.log: "Dog tab is now showing"

textarea

The textarea is an extended label widget which displays a cursor and allows the user to input text. Long lines are wrapped and when the text becomes long enough the text area can be scrolled. It supports one line mode and password mode, where typed characters are replaced visually with bullets or asterisks.

../../_images/lvgl_textarea.png

Configuration variables:

  • accepted_chars (Optional, string): You can set a list of accepted characters, so other characters will be ignored.

  • max_length (Optional, int): Limit the maximum number of characters to this value.

  • one_line (Optional, boolean): The text area can be limited to only allow a single line of text. In this case the height will set automatically to fit only one line, line break characters will be ignored, and word wrap will be disabled.

  • password_mode (Optional, boolean): The text area supports password mode. By default, if the (bullet, 0x2022) glyph exists in the font, the entered characters are converted to it after some time or when a new character is entered. If is missing from the font, * (asterisk) will be used.

  • text (Optional, Text property): Initial contents of the textarea.

  • placeholder_text (Optional, Text property): A placeholder text can be specified, which is displayed when the Text area is empty.

  • any Styling and state-based option for the background of the textarea. Uses all the typical background style properties and the text/label related style properties for the text.

Actions:

  • lvgl.textarea.update action updates the widget’s text property, to replace the entire text content.
    • id (Required): The ID or a list of IDs of textarea widgets which you want update.

    • text (Optional, Text property): The text to replace the textarea content.

Triggers:

  • on_value trigger is activated on every keystroke.

  • on_ready trigger is activated when one_line is configured as true and the newline character is received (Enter/Ready key on the keyboard).

  • interaction LVGL event triggers.

For both triggers above, when triggered, the variable text (std::string type) is available for use in lambdas within these triggers and it will contain the entire contents of the textarea.

Example:

# Example widget:
- textarea:
    id: textarea_id
    one_line: true
    placeholder_text: "Enter text here"

# Example action:
on_...:
  then:
    - lvgl.textarea.update:
        id: textarea_id
        text: "Hello World!"

# Example trigger:
- textarea:
    ...
    on_value:
      then:
        - logger.log:
            format: "Textarea changed to: %s"
            args: [ text.c_str() ]
    on_ready:
      then:
        - logger.log:
            format: "Textarea ready: %s"
            args: [ text.c_str() ]

The textarea can be also integrated as Text or Text Sensor component.

tileview

The tileview is a container object whose elements, called tiles, can be arranged in grid form. A user can navigate between the tiles by dragging or swiping. Any direction can be disabled on the tiles individually to not allow moving from one tile to another.

If the Tile view is screen sized, the user interface resembles what you may have seen on smartwatches.

Configuration variables:

  • tiles (Required, list): A list with (any number of) tiles to be added to tileview.
    • column (Required): Vertical position of the tile in the tileview grid.

    • row (Required): Horizontal position of the tile in the tileview grid.

    • dir (Optional): Enable moving to adjacent tiles in the given direction by swiping/dragging. One (or multiple as YAML list) of LEFT, RIGHT, TOP, BOTTOM, HOR, VER, ALL. Defaults to ALL.

    • id (Optional): A tile ID to be used with the lvgl.tileview.select action.

    • widgets (Optional, list): A list of LVGL Widgets to be drawn on the tile, as children.

Actions:

  • lvgl.tileview.select action jumps the tileview to the desired tile:
    • animated (Optional, boolean): To animate the movement. Defaults to false.

    • column (Optional): Vertical position of the tile to which to jump. Required if not specifying tile_id.

    • row (Optional): Horizontal position of the tile to which to jump. Required if not specifying tile_id.

    • id (Required): The ID of the tileview which receives this action.

    • tile_id (Optional): The ID of the tile (from within the tileview) to which to jump. Required if not specifying row and column.

Triggers:

  • on_value trigger is activated when displayed tile changes. The new value is returned in the variable tile as the ID of the now-visible tile.

  • interaction LVGL event triggers.

Example:

# Example widget:
- tileview:
    id: tiv_id
    tiles:
      - id: cat_tile
        row: 0
        column: 0
        dir: VER
        widgets:
          - image:
              src: cat_image
          - ...
      - ...

# Example action:
on_...:
  then:
    - lvgl.tileview.select:
        id: tiv_id
        tile_id: cat_tile
        animated: true

# Example trigger:
- tileview:
    ...
    on_value:
      - if:
          condition:
            lambda: return tile == id(cat_tile);
          then:
            - logger.log: "Cat tile is now showing"

Automations

Actions

As outlined in the sections above, each widget type supports several of its own, unique actions. Several universal actions are also available for all widgets, these are outlined below.

lvgl.widget.update

This powerful action allows changing/updating any widget’s common style property, state (templatable) or flag on the fly.

  • id (Required): The ID or a list of IDs of widgets configured in LVGL which you want update.

  • The widget’s common style property, state (templatable) or flag.

# Example for updating styles (in states):
on_...:
  then:
    - lvgl.widget.update:
        id: my_button_id
        bg_color: 0xFF0000
        state:
          disabled: true

# Example for updating flag:
on_...:
  then:
    - lvgl.widget.update:
        id: my_label_id
        hidden: true

Check out in the Cookbook Remote light button for an example which demonstrates how to use a template to update the state.

lvgl.widget.hide, lvgl.widget.show

These actions are shorthands for toggling the hidden flag of any widget.

  • id (Required): The ID or a list of IDs of widgets configured in LVGL which you want to hide or show.

on_...:
  then:
    - lvgl.widget.hide: my_label_id                # a single widget
    - lvgl.widget.show: [my_button_1, my_button_2] # a list of widgets
    - delay: 0.5s
    - lvgl.widget.show:
        -id: my_label_id
    - lvgl.widget.hide:
        - id: [my_button_1, my_button_2]

lvgl.widget.disable, lvgl.widget.enable

These actions are shorthands for toggling the disabled state of any widget (which controls the appearance of the corresponding disabled style set of the theme):

  • id (Required): The ID or a list of IDs of widgets configured in LVGL which you want to disable or enable.

- on_...:
    then:
      - lvgl.widget.disable:
          - my_button_1
          - my_button_2

- on_...:
    then:
      - lvgl.widget.enable:
          - id: my_button_1
          - id: my_button_2

Triggers

Specific triggers like on_value are available for certain widgets; they are described above in their respective section. Some universal triggers are also available for all of the widgets:

ESPHome implements as universal triggers the following interaction events generated by LVGL:

  • on_press: The widget has been pressed.

  • on_long_press: The widget has been pressed for at least the long_press_time specified in the input device configuration. Not called if scrolled.

  • on_long_press_repeat: Called after long_press_time in every long_press_repeat_time ms. Not called if scrolled.

  • on_short_click: The widget was pressed for a short period of time, then released. Not called if scrolled or long pressed.

  • on_click: Called on release if a widget did not scroll (regardless of long press).

  • on_release: Called in every case when a widget has been released.

  • on_scroll_begin: Scrolling of the widget begins.

  • on_scroll_end: Scrolling of the widget ends.

  • on_scroll: The widget was scrolled.

  • on_focus: The widget is focused.

  • on_defocus: The widget is unfocused.

  • on_all_events: Will be triggered on any event sent to the widget - this is useful for debugging.

These triggers can be applied directly to any widget in the LVGL configuration, given that the widget itself supports generating such events. For the widgets having a value, the triggers return the current value in variable x; this variable may be used in lambdas defined within those triggers.

Each trigger also deliver an event parameter, which is a pointer to the LVGL C type lv_event_t. This may be used in lambdas defined within those triggers. Refer to the LVGL documentation for more information.

There are additional triggers for pages - each page may have an on_load and on_unload trigger. These will be called when the page becomes active or inactive respectively.

# Example triggers:
- button:
    ...
    on_short_click:
      then:
        lvgl.page.show: main_page
    on_long_press:
      then:
        light.toggle: display_backlight

- slider:
    ...
    on_release:
      then:
        - light.turn_on:
            id: display_backlight
            transition_length: 0ms
            brightness: !lambda return x / 100;

See Also