Builtin Elements

Common properties

Geometry

These properties are valid on all visible items:

  • width and height (in length): The size of the element. When set, this overrides the default size.

  • x and y (in length): The position of the element relative to its parent.

  • z (in float): Allows to specify a different order to stack the items with its siblings. (default value: 0)

  • absolute-position (in Point): The position of the element within the contained window.

Layout

These properties are valid on all visible items and can be used to specify constraints when used in layouts:

  • col, row, colspan, rowspan (in int): See GridLayout.

  • horizontal-stretch and vertical-stretch (in-out float): Specify how much relative space these elements are stretching in a layout. When 0, this means that the elements won’t be stretched unless all elements are 0. Builtin widgets have a value of either 0 or 1.

  • max-width and max-height (in length): The maximum size of an element

  • min-width and min-height (in length): The minimum size of an element

  • preferred-width and preferred-height (in length): The preferred size of an element

Miscellaneous

  • cache-rendering-hint (in bool): When set to true, this provides a hint to the renderer to cache the contents of the element and all the children into an intermediate cached layer. For complex sub-trees that rarely change this may speed up the rendering, at the expense of increased memory consumption. Not all rendering backends support this, so this is merely a hint. (default value: false)

  • dialog-button-role (in enum DialogButtonRole): Specify that this is a button in a Dialog.

  • opacity (in float): A value between 0 and 1 (or a percentage) that is used to draw the element and its children with transparency. 0 is fully transparent (invisible), and 1 is fully opaque. The opacity is applied to the tree of child elements as if they were first drawn into an intermediate layer, and then the whole layer is rendered with this opacity. (default value: 1)

  • visible (in bool): When set to false, the element and all his children won’t be drawn and not react to mouse input (default value: true)

The following example demonstrates the opacity property with children. An opacity is applied to the red rectangle. Since the green rectangle is a child of the red one, you can see the gradient underneath it, but you can’t see the red rectangle through the green one.

export component Example inherits Window {
    width: 100px;
    height: 100px;
    background: @radial-gradient(circle, black, white, black, white);
    Rectangle {
        opacity: 0.5;
        background: red;
        border-color: #822;
        border-width: 5px;
        width: 50px; height: 50px;
        x: 10px; y: 10px;
        Rectangle {
            background: green;
            border-color: #050;
            border-width: 5px;
            width: 50px; height: 50px;
            x: 25px; y: 25px;
        }
    }
}

Accessibility

Use the following accessible- properties to make your items interact well with software like screen readers, braille terminals and other software to make your application accessible. accessible-role must be set in order to be able to set any other accessible property or callback.

  • accessible-role (in enum AccessibleRole): The role of the element. This property is mandatory to be able to use any other accessible properties. It should be set to a constant value. (default value: none for most elements, but text for the Text element)

  • accessible-checkable (in bool): Whether the element is can be checked or not.

  • accessible-checked (in bool): Whether the element is checked or not. This maps to the “checked” state of checkboxes, radio buttons, and other widgets.

  • accessible-description (in string): The description for the current element.

  • accessible-label (in string): The label for an interactive element. (default value: empty for most elements, or the value of the text property for Text elements)

  • accessible-value-maximum (in float): The maximum value of the item. This is used for example by spin boxes.

  • accessible-value-minimum (in float): The minimum value of the item.

  • accessible-value-step (in float) The smallest increment or decrement by which the current value can change. This corresponds to the step by which a handle on a slider can be dragged.

  • accessible-value (in string): The current value of the item.

  • accessible-placeholder-text (in string): A placeholder text to use when the item’s value is empty. Applies to text elements.

You can also use the following callbacks that are going to be called by the accessibility framework:

  • accessible-action-default(): Invoked when the default action for this widget is requested (eg: pressed for a button).

  • accessible-action-set-value(string): Invoked when the user wants to change the accessible value.

  • accessible-action-increment(): Invoked when the user requests to increment the value.

  • accessible-action-decrement(): Invoked when the user requests to decrement the value.

Drop Shadows

To achieve the graphical effect of a visually elevated shape that shows a shadow effect underneath the frame of an element, it’s possible to set the following drop-shadow properties:

  • drop-shadow-blur (in length): The radius of the shadow that also describes the level of blur applied to the shadow. Negative values are ignored and zero means no blur. (default value: 0)

  • drop-shadow-color (in color): The base color of the shadow to use. Typically that color is the starting color of a gradient that fades into transparency.

  • drop-shadow-offset-x and drop-shadow-offset-y (in length): The horizontal and vertical distance of the shadow from the element’s frame. A negative value places the shadow left / above of the element.

The drop-shadow effect is supported for Rectangle elements.

Dialog

Dialog is like a window, but it has buttons that are automatically laid out.

A Dialog should have one main element as child, that isn’t a button. The dialog can have any number of StandardButton widgets or other buttons with the dialog-button-role property. The buttons will be placed in an order that depends on the target platform at run-time.

The kind property of the StandardButtons and the dialog-button-role properties need to be set to a constant value, it can’t be an arbitrary variable expression. There can’t be several StandardButtons of the same kind.

A callback <kind>_clicked is automatically added for each StandardButton which doesn’t have an explicit callback handler, so it can be handled from the native code: For example if there is a button of kind cancel, a cancel_clicked callback will be added.

Properties

  • icon (in image): The window icon shown in the title bar or the task bar on window managers supporting it.

  • title (in string): The window title that is shown in the title bar.

Example

import { StandardButton, Button } from "std-widgets.slint";
export component Example inherits Dialog {
    Text {
      text: "This is a dialog box";
    }
    StandardButton { kind: ok; }
    StandardButton { kind: cancel; }
    Button {
      text: "More Info";
      dialog-button-role: action;
    }
}

Flickable

The Flickable is a low-level element that is the base for scrollable widgets, such as the ScrollView. When the viewport-width or the viewport-height is greater than the parent’s width or height respectively, the element becomes scrollable. Note that the Flickable doesn’t create a scrollbar. When unset, the viewport-width and viewport-height are calculated automatically based on the Flickable’s children. This isn’t the case when using a for loop to populate the elements. This is a bug tracked in issue #407. The maximum and preferred size of the Flickable are based on the viewport.

When not part of a layout, its width or height defaults to 100% of the parent element when not specified.

Pointer Event Interaction

If the Flickable’s area contains elements that use TouchArea to act on clicking, such as Button widgets, then the following algorithm is used to distinguish between the user’s intent of scrolling or interacting with TouchArea elements:

  1. If the Flickable’s interactive property is false, all events are forwarded to elements underneath.

  2. If a press event is received where the event’s coordinates interact with a TouchArea, the event is stored and any subsequent move and release events are handled as follows:

    1. If 100ms elapse without any events, the stored press event is delivered to the TouchArea.

    2. If a release event is received before 100ms have elapsed, the stored press event as well as the release event are immediately delivered to the TouchArea and the algorithm resets.

    3. Any move events received will start a flicking operation on the Flickable if all of the following conditions are met:

      1. The event is received before 500ms have elapsed since receiving the press event.

      2. The distance to the press event exceeds 8 logical pixels in an orientation in which we are allowed to move. If Flickable decides to flick, any press event sent previously to a TouchArea, is followed up by an exit event. During the phase of receiving move events, the flickable follows the coordinates.

  3. If the interaction of press, move, and release events begins at coordinates that do not intersect with a TouchArea, then Flickable will flick immediately on pointer move events when the euclidean distance to the coordinates of the press event exceeds 8 logical pixels.

Properties

  • interactive (in bool): When true, the viewport can be scrolled by clicking on it and dragging it with the cursor. (default value: true)

  • viewport-height, viewport-width (in length): The total size of the scrollable element.

  • viewport-x, viewport-y (in length): The position of the scrollable element relative to the Flickable. This is usually a negative value.

Callbacks

  • flicked(): Invoked when viewport-x or viewport-y is changed by a user action (dragging, scrolling).

Example

export component Example inherits Window {
    width: 270px;
    height: 100px;

    Flickable {
        viewport-height: 300px;
        Text {
            x:0;
            y: 150px;
            text: "This is some text that you have to scroll to see";
        }
    }
}

FocusScope

The FocusScope exposes callbacks to intercept key events. Note that FocusScope will only invoke them when it has-focus.

The KeyEvent has a text property, which is a character of the key entered. When a non-printable key is pressed, the character will be either a control character, or it will be mapped to a private unicode character. The mapping of these non-printable, special characters is available in the Key namespace

Properties

  • has-focus (out bool): Is true when the element has keyboard focus.

  • enabled (in bool): When true, the FocusScope will make itself the focused element when clicked. Set this to false if you don’t want the click-to-focus behavior. Similarly, a disabled FocusScope does not accept the focus via tab focus traversal. A parent FocusScope will still receive key events from child FocusScopes that were rejected, even if enabled is set to false. (default value: true)

Functions

  • focus() Call this function to transfer keyboard focus to this FocusScope, to receive future KeyEvents.

  • clear-focus() Call this function to remove keyboard focus from this FocusScope if it currently has the focus. See also Focus Handling.

Callbacks

  • key-pressed(KeyEvent) -> EventResult: Invoked when a key is pressed, the argument is a KeyEvent struct. The returned EventResult indicates whether to accept or ignore the event. Ignored events are forwarded to the parent element.

  • key-released(KeyEvent) -> EventResult: Invoked when a key is released, the argument is a KeyEvent struct. The returned EventResult indicates whether to accept or ignore the event. Ignored events are forwarded to the parent element.

  • focus-changed-event(): Invoked when the focus on the FocusScope has changed.

Example

export component Example inherits Window {
    width: 100px;
    height: 100px;
    forward-focus: my-key-handler;
    my-key-handler := FocusScope {
        key-pressed(event) => {
            debug(event.text);
            if (event.modifiers.control) {
                debug("control was pressed during this event");
            }
            if (event.text == Key.Escape) {
                debug("Esc key was pressed")
            }
            accept
        }
    }
}

GridLayout

GridLayout places its children in a grid. GridLayout adds properties to each child: col, row, colspan, rowspan. You can control the position of children with col and row. If col or row aren’t specified, they are automatically computed such that the item is next to the previous item, in the same row. Alternatively, the item can be put in a Row element.

Properties

  • spacing (in length): The distance between the elements in the layout.

  • spacing-horizontal, spacing-vertical (in length): Set these properties to override the spacing on specific directions.

  • padding (in length): The padding within the layout.

  • padding-left, padding-right, padding-top and padding-bottom (in length): Set these properties to override the padding on specific sides.

Examples

This example uses the Row element:

export component Foo inherits Window {
    width: 200px;
    height: 200px;
    GridLayout {
        spacing: 5px;
        Row {
            Rectangle { background: red; }
            Rectangle { background: blue; }
        }
        Row {
            Rectangle { background: yellow; }
            Rectangle { background: green; }
        }
    }
}

This example uses the col and row properties

export component Foo inherits Window {
    width: 200px;
    height: 150px;
    GridLayout {
        Rectangle { background: red; }
        Rectangle { background: blue; }
        Rectangle { background: yellow; row: 1; }
        Rectangle { background: green; }
        Rectangle { background: black; col: 2; row: 0; }
    }
}

Image

An Image can be used to represent an image loaded from a file.

Properties

  • colorize (in brush): When set, the image is used as an alpha mask and is drawn in the given color (or with the gradient).

  • horizontal-alignment (in enum ImageHorizontalAlignment): The horizontal alignment of the image within the element.

  • horizontal-tiling (in enum ImageTiling): Whether the image should be tiled on the horizontal axis.

  • image-fit (in enum ImageFit): Specifies how the source image shall be fit into the image element. Does not have any effect when used with 9 slice scaled or tiled images. (default value: contain when the Image element is part of a layout, fill otherwise)

  • image-rendering (in enum ImageRendering): Specifies how the source image will be scaled. (default value: smooth)

  • rotation-angle (in angle), rotation-origin-x (in length), rotation-origin-y (in length): Rotates the image by the given angle around the specified origin point. The default origin point is the center of the element. When these properties are set, the Image can’t have children.

  • source (in image): The image to load. Use the @image-url("...") macro to specify the location of the image.

  • source-clip-x, source-clip-y, source-clip-width, source-clip-height (in int): Properties in source image coordinates that define the region of the source image that is rendered. By default the entire source image is visible:

    Property

    Default Binding

    source-clip-x

    0

    source-clip-y

    0

    source-clip-width

    source.width - source-clip-x

    source-clip-height

    source.height - source-clip-y

  • vertical-alignment (in enum ImageVerticalAlignment): The vertical alignment of the image within the element.

  • vertical-tiling (in enum ImageTiling): Whether the image should be tiled on the vertical axis.

  • width, height (in length): The width and height of the image as it appears on the screen.The default values are the sizes provided by the source image. If the Image is not in a layout and only one of the two sizes are specified, then the other defaults to the specified value scaled according to the aspect ratio of the source image.

Example

export component Example inherits Window {
    width: 100px;
    height: 100px;
    VerticalLayout {
        Image {
            source: @image-url("https://slint.dev/logo/slint-logo-full-light.svg");
            // image-fit default is `contain` when in layout, preserving aspect ratio
        }
        Image {
            source: @image-url("https://slint.dev/logo/slint-logo-full-light.svg");
            colorize: red;
        }
    }
}

Scaled while preserving the aspect ratio:

export component Example inherits Window {
    width: 100px;
    height: 150px;
    VerticalLayout {
        Image {
            source: @image-url("https://slint.dev/logo/slint-logo-full-light.svg");
            width: 100px;
            // implicit default, preserving aspect ratio:
            // height: self.width * natural_height / natural_width;
        }
    }
}

Example using nine-slice:

export component Example inherits Window {
    width: 100px;
    height: 150px;
    VerticalLayout {
        Image {
            source: @image-url("https://interactive-examples.mdn.mozilla.net/media/examples/border-diamonds.png", nine-slice(30));
        }
    }
}

Path

The Path element allows rendering a generic shape, composed of different geometric commands. A path shape can be filled and outlined.

When not part of a layout, its width or height defaults to 100% of the parent element when not specified.

A path can be defined in two different ways:

  • Using SVG path commands as a string

  • Using path command elements in .slint markup.

The coordinates used in the geometric commands are within the imaginary coordinate system of the path. When rendering on the screen, the shape is drawn relative to the x and y properties. If the width and height properties are non-zero, then the entire shape is fit into these bounds - by scaling accordingly.

Common Path Properties

  • fill (in brush): The color for filling the shape of the path.

  • fill-rule (in enum FillRule): The fill rule to use for the path. (default value: nonzero)

  • stroke (in brush): The color for drawing the outline of the path.

  • stroke-width (in length): The width of the outline.

  • width (in length): If non-zero, the path will be scaled to fit into the specified width.

  • height (in length): If non-zero, the path will be scaled to fit into the specified height.

  • viewbox-x/viewbox-y/viewbox-width/viewbox-height (in float) These four properties allow defining the position and size of the viewport of the path in path coordinates.

    If the viewbox-width or viewbox-height is less or equal than zero, the viewbox properties are ignored and instead the bounding rectangle of all path elements is used to define the view port.

  • clip (in bool): By default, when a path has a view box defined and the elements render outside of it, they are still rendered. When this property is set to true, then rendering will be clipped at the boundaries of the view box. This property must be a literal true or false (default value: false)

Path Using SVG commands

SVG is a popular file format for defining scalable graphics, which are often composed of paths. In SVG paths are composed using commands, which in turn are written in a string. In .slint the path commands are provided to the commands property. The following example renders a shape consists of an arc and a rectangle, composed of line-to, move-to and arc commands:

export component Example inherits Path {
    width: 100px;
    height: 100px;
    commands: "M 0 0 L 0 100 A 1 1 0 0 0 100 100 L 100 0 Z";
    stroke: red;
    stroke-width: 1px;
}

The commands are provided in a property:

  • commands (in string): A string providing the commands according to the SVG path specification.

Path Using SVG Path Elements

The shape of the path can also be described using elements that resemble the SVG path commands but use the .slint markup syntax. The earlier example using SVG commands can also be written like that:

export component Example inherits Path {
    width: 100px;
    height: 100px;
    stroke: blue;
    stroke-width: 1px;

    MoveTo {
        x: 0;
        y: 0;
    }
    LineTo {
        x: 0;
        y: 100;
    }
    ArcTo {
        radius-x: 1;
        radius-y: 1;
        x: 100;
        y: 100;
    }
    LineTo {
        x: 100;
        y: 0;
    }
    Close {
    }
}

Note how the coordinates of the path elements don’t use units - they operate within the imaginary coordinate system of the scalable path.

MoveTo Sub-element for Path

The MoveTo sub-element closes the current sub-path, if present, and moves the current point to the location specified by the x and y properties. Subsequent elements such as LineTo will use this new position as their starting point, therefore this starts a new sub-path.

Properties
  • x (in float): The x position of the new current point.

  • y (in float): The y position of the new current point.

LineTo Sub-element for Path

The LineTo sub-element describes a line from the path’s current position to the location specified by the x and y properties.

Properties
  • x (in float): The target x position of the line.

  • y (in float): The target y position of the line.

ArcTo Sub-element for Path

The ArcTo sub-element describes the portion of an ellipse. The arc is drawn from the path’s current position to the location specified by the x and y properties. The remaining properties are modelled after the SVG specification and allow tuning visual features such as the direction or angle.

Properties
  • large-arc (in bool): Out of the two arcs of a closed ellipse, this flag selects that the larger arc is to be rendered. If the property is false, the shorter arc is rendered instead.

  • radius-x (in float): The x-radius of the ellipse.

  • radius-y (in float): The y-radius of the ellipse.

  • sweep (in bool): If the property is true, the arc will be drawn as a clockwise turning arc; anti-clockwise otherwise.

  • x-rotation (in float): The x-axis of the ellipse will be rotated by the value of this properties, specified in as angle in degrees from 0 to 360.

  • x (in float): The target x position of the line.

  • y (in float): The target y position of the line.

CubicTo Sub-element for Path

The CubicTo sub-element describes a smooth Bézier from the path’s current position to the location specified by the x and y properties, using two control points specified by their respective properties.

Properties
  • control-1-x (in float): The x coordinate of the curve’s first control point.

  • control-1-y (in float): The y coordinate of the curve’s first control point.

  • control-2-x (in float): The x coordinate of the curve’s second control point.

  • control-2-y (in float): The y coordinate of the curve’s second control point.

  • x (in float): The target x position of the curve.

  • y (in float): The target y position of the curve.

QuadraticTo Sub-element for Path

The QuadraticTo sub-element describes a smooth Bézier from the path’s current position to the location specified by the x and y properties, using the control points specified by the control-x and control-y properties.

Properties
  • control-x (in float): The x coordinate of the curve’s control point.

  • control-y (in float): The y coordinate of the curve’s control point.

  • x (in float): The target x position of the curve.

  • y (in float): The target y position of the curve.

Close Sub-element for Path

The Close element closes the current sub-path and draws a straight line from the current position to the beginning of the path.

Rectangle

By default, a Rectangle is just an empty item that shows nothing. By setting a color or configuring a border, it’s then possible to draw a rectangle on the screen.

When not part of a layout, its width and height default to 100% of the parent element.

Properties

  • background (in brush): The background brush of this Rectangle, typically a color. (default value: transparent)

  • border-color (in brush): The color of the border. (default value: transparent)

  • border-radius (in length): The size of the radius. (default value: 0)

  • border-top-left-radius, border-top-right-radius, border-bottom-left-radius and border-bottom-right-radius (in length): Set these properties to override the radius for specific corners.

  • border-width (in length): The width of the border. (default value: 0)

  • clip (in bool): By default, when an element is bigger or outside another element, it’s still shown. When this property is set to true, the children of this Rectangle are clipped to the border of the rectangle. (default value: false)

Example

export component Example inherits Window {
    width: 270px;
    height: 100px;

    Rectangle {
        x: 10px;
        y: 10px;
        width: 50px;
        height: 50px;
        background: blue;
    }

    // Rectangle with a border
    Rectangle {
        x: 70px;
        y: 10px;
        width: 50px;
        height: 50px;
        background: green;
        border-width: 2px;
        border-color: red;
    }

    // Transparent Rectangle with a border and a radius
    Rectangle {
        x: 140px;
        y: 10px;
        width: 50px;
        height: 50px;
        border-width: 4px;
        border-color: black;
        border-radius: 10px;
    }

    // A radius of width/2 makes it a circle
    Rectangle {
        x: 210px;
        y: 10px;
        width: 50px;
        height: 50px;
        background: yellow;
        border-width: 2px;
        border-color: blue;
        border-radius: self.width/2;
    }
}

TextInput

The TextInput is a lower-level item that shows text and allows entering text.

When not part of a layout, its width or height defaults to 100% of the parent element when not specified.

Properties

  • color (in brush): The color of the text (default value: depends on the style)

  • font-family (in string): The name of the font family selected for rendering the text.

  • font-size (in length): The font size of the text.

  • font-weight (in int): The weight of the font. The values range from 100 (lightest) to 900 (thickest). 400 is the normal weight.

  • font-italic (in bool): Whether or not the font face should be drawn italicized or not. (default value: false)

  • has-focus (out bool): TextInput sets this to true when it’s focused. Only then it receives KeyEvents.

  • horizontal-alignment (in enum TextHorizontalAlignment): The horizontal alignment of the text.

  • input-type (in enum InputType): Use this to configure TextInput for editing special input, such as password fields. (default value: text)

  • letter-spacing (in length): The letter spacing allows changing the spacing between the glyphs. A positive value increases the spacing and a negative value decreases the distance. (default value: 0)

  • read-only (in bool): When set to true, text editing via keyboard and mouse is disabled but selecting text is still enabled as well as editing text programatically. (default value: false)

  • selection-background-color (in color): The background color of the selection.

  • selection-foreground-color (in color): The foreground color of the selection.

  • single-line (in bool): When set to true, the text is always rendered as a single line, regardless of new line separators in the text. (default value: true)

  • text-cursor-width (in length): The width of the text cursor. (default value: provided at run-time by the selected widget style)

  • text (in-out string): The text rendered and editable by the user.

  • vertical-alignment (in enum TextVerticalAlignment): The vertical alignment of the text.

  • wrap (in enum TextWrap): The way the text input wraps. Only makes sense when single-line is false. (default value: no-wrap)

Functions

  • focus() Call this function to focus the text input and make it receive future keyboard events.

  • clear-focus() Call this function to remove keyboard focus from this TextInput if it currently has the focus. See also Focus Handling.

  • set-selection-offsets(int, int) Selects the text between two UTF-8 offsets.

  • select-all() Selects all text.

  • clear-selection() Clears the selection.

  • copy() Copies the selected text to the clipboard.

  • cut() Copies the selected text to the clipboard and removes it from the editable area.

  • paste() Pastes the text content of the clipboard at the cursor position.

Callbacks

  • accepted(): Invoked when enter key is pressed.

  • cursor-position-changed(Point): The cursor was moved to the new (x, y) position described by the Point argument.

  • edited(): Invoked when the text has changed because the user modified it.

Example

export component Example inherits Window {
    width: 270px;
    height: 100px;

    TextInput {
        text: "Replace me with a name";
    }
}

Text

The Text element is responsible for rendering text. Besides the text property, that specifies which text to render, it also allows configuring different visual aspects through the font-family, font-size, font-weight, color, and stroke properties.

The Text element can break long text into multiple lines of text. A line feed character (\n) in the string of the text property will trigger a manual line break. For automatic line breaking you need to set the wrap property to a value other than no-wrap, and it’s important to specify a width and height for the Text element, in order to know where to break. It’s recommended to place the Text element in a layout and let it set the width and height based on the available screen space and the text itself.

Properties

  • color (in brush): The color of the text. (default value: depends on the style)

  • font-family (in string): The name of the font family selected for rendering the text.

  • font-size (in length): The font size of the text.

  • font-weight (in int): The weight of the font. The values range from 100 (lightest) to 900 (thickest). 400 is the normal weight.

  • font-italic (in bool): Whether or not the font face should be drawn italicized or not. (default value: false)

  • horizontal-alignment (in enum TextHorizontalAlignment): The horizontal alignment of the text.

  • letter-spacing (in length): The letter spacing allows changing the spacing between the glyphs. A positive value increases the spacing and a negative value decreases the distance. (default value: 0)

  • overflow (in enum TextOverflow): What happens when the text overflows (default value: clip).

  • text (in string): The text rendered.

  • vertical-alignment (in enum TextVerticalAlignment): The vertical alignment of the text.

  • wrap (in enum TextWrap): The way the text wraps (default value: no-wrap).

  • stroke (in brush): The brush used for the text outline (default value: transparent).

  • stroke-width (in length): The width of the text outline. If the width is zero, then a hairline stroke (1 physical pixel) will be rendered.

  • stroke-style (in enum TextStrokeStyle): The style/alignment of the text outline (default value: outside).

  • rotation-angle (in angle), rotation-origin-x (in length), rotation-origin-y (in length): Rotates the text by the given angle around the specified origin point. The default origin point is the center of the element. When these properties are set, the Text can’t have children.

Example

This example shows the text “Hello World” in red, using the default font:

export component Example inherits Window {
    width: 270px;
    height: 100px;

    Text {
        x:0;y:0;
        text: "Hello World";
        color: red;
    }
}

This example breaks a longer paragraph of text into multiple lines, by setting a wrap policy and assigning a limited width and enough height for the text to flow down:

export component Example inherits Window {
    width: 270px;
    height: 300px;

    Text {
        x:0;
        text: "This paragraph breaks into multiple lines of text";
        wrap: word-wrap;
        width: 150px;
        height: 100%;
    }
}

TouchArea

Use TouchArea to control what happens when the region it covers is touched or interacted with using the mouse.

When not part of a layout, its width or height default to 100% of the parent element.

Properties

  • has-hover (out bool): TouchArea sets this to true when the mouse is over it.

  • mouse-cursor (in enum MouseCursor): The mouse cursor type when the mouse is hovering the TouchArea.

  • mouse-x, mouse-y (out length): Set by the TouchArea to the position of the mouse within it.

  • pressed-x, pressed-y (out length): Set by the TouchArea to the position of the mouse at the moment it was last pressed.

  • pressed (out bool): Set to true by the TouchArea when the mouse is pressed over it.

Callbacks

  • clicked(): Invoked when clicked: A finger or the left mouse button is pressed, then released on this element.

  • double-clicked(): Invoked when double-clicked. The left mouse button is pressed and released twice on this element in a short period of time, or the same is done with a finger. The clicked() callbacks will be triggered before the double-clicked() callback is triggered.

  • moved(): The mouse or finger has been moved. This will only be called if the mouse is also pressed or the finger continues to touch the display. See also pointer-event(PointerEvent).

  • pointer-event(PointerEvent): Invoked when a button was pressed or released, a finger touched, or the pointer moved. The PointerEvent argument contains information such which button was pressed and any active keyboard modifiers. In the PointerEventKind::Move case the buttons field will always be set to PointerEventButton::Other, independent of whether any button is pressed or not.

  • scroll-event(PointerScrollEvent) -> EventResult: Invoked when the mouse wheel was rotated or another scroll gesture was made. The PointerScrollEvent argument contains information about how much to scroll in what direction. The returned EventResult indicates whether to accept or ignore the event. Ignored events are forwarded to the parent element.

Example

export component Example inherits Window {
    width: 200px;
    height: 100px;
    area := TouchArea {
        width: parent.width;
        height: parent.height;
        clicked => {
            rect2.background = #ff0;
        }
    }
    Rectangle {
        x:0;
        width: parent.width / 2;
        height: parent.height;
        background: area.pressed ? blue: red;
    }
    rect2 := Rectangle {
        x: parent.width / 2;
        width: parent.width / 2;
        height: parent.height;
    }
}

VerticalLayout and HorizontalLayout

These layouts place their children next to each other vertically or horizontally. The size of elements can either be fixed with the width or height property, or if they aren’t set they will be computed by the layout respecting the minimum and maximum sizes and the stretch factor.

Properties

  • spacing (in length): The distance between the elements in the layout.

  • padding (in length): the padding within the layout.

  • padding-left, padding-right, padding-top and padding-bottom (in length): Set these properties to override the padding on specific sides.

  • alignment (in enum LayoutAlignment): Set the alignment. Matches the CSS flex box.

Example

export component Foo inherits Window {
    width: 200px;
    height: 100px;
    HorizontalLayout {
        spacing: 5px;
        Rectangle { background: red; width: 10px; }
        Rectangle { background: blue; min-width: 10px; }
        Rectangle { background: yellow; horizontal-stretch: 1; }
        Rectangle { background: green; horizontal-stretch: 2; }
    }
}

Window

Window is the root of the tree of elements that are visible on the screen.

The Window geometry will be restricted by its layout constraints: Setting the width will result in a fixed width, and the window manager will respect the min-width and max-width so the window can’t be resized bigger or smaller. The initial width can be controlled with the preferred-width property. The same applies to the Windows height.

Properties

  • always-on-top (in bool): Whether the window should be placed above all other windows on window managers supporting it.

  • background (in brush): The background brush of the Window. (default value: depends on the style)

  • default-font-family (in string): The font family to use as default in text elements inside this window, that don’t have their font-family property set.

  • default-font-size (in-out length): The font size to use as default in text elements inside this window, that don’t have their font-size property set. The value of this property also forms the basis for relative font sizes.

  • default-font-weight (in int): The font weight to use as default in text elements inside this window, that don’t have their font-weight property set. The values range from 100 (lightest) to 900 (thickest). 400 is the normal weight.

  • icon (in image): The window icon shown in the title bar or the task bar on window managers supporting it.

  • no-frame (in bool): Whether the window should be borderless/frameless or not.

  • resize-border-width (in length): Size of the resize border in borderless/frameless windows (winit only for now).

  • title (in string): The window title that is shown in the title bar.