APL Frame (APL 1.4 to 1.5)


(This is not the most recent version of APL. Use the Other Versions option to see the documentation for the most recent version of APL)

A Frame holds a single child and has a border and background color.

Properties

The Frame component has the following properties in addition to the base component properties. See the meaning of the columns.

Ensure that you include height and width in your Frame definition.

Property Type Default Styled Dynamic Description

backgroundColor

Color

none

Yes

Yes

Background color.

borderBottomLeftRadius

Non-negative Absolute Dimension

none

Yes

No

Radius of the bottom-left corner. Overrides borderRadius.

borderBottomRightRadius

Non-negative Absolute Dimension

none

Yes

No

Radius of the bottom-right corner. Overrides borderRadius.

borderColor

Color

none

Yes

Yes

Color of the border.

borderRadius

Non-negative Absolute Dimension

0

Yes

No

Corner radius for rounded-rectangle variant.

borderStrokeWidth

Non-negative Absolute Dimension

borderWidth

Yes

Yes

Width of the border stroke.

borderTopLeftRadius

Non-negative Absolute Dimension

none

Yes

No

Radius of the top-left corner. Overrides borderRadius if specified.

borderTopRightRadius

Non-negative Absolute Dimension

none

Yes

No

Radius of the top-right corner. Overrides borderRadius if specified.

borderWidth

Non-negative Absolute Dimension

0

Yes

No

Width of the border.

item

Array of components and layouts to display inside the Frame.

[]

No

No

Child component

When the Frame is the source or target of an event, the following values are reported in event.source or event.target:

{
  // Frame-specific values
  "type": "Frame",

  // General component values
  "bind": Map,         // Access to component data-binding context
  "checked": Boolean,  // Checked state
  "disabled": Boolean, // Disabled state
  "focused": Boolean,  // Focused state
  "height": Number,    // Height of the component, in dp (includes the padding)
  "id": ID,            // ID of the component
  "opacity": Number,   // Opacity of the component [0-1]
  "pressed": Boolean,  // Pressed state
  "uid": UID,          // Runtime-generated unique ID of the component
  "width": Number      // Width of the component, in dp (includes the padding)
}

backgroundColor

The color of the background. The background is drawn inside of the border.

borderRadius properties

Dimensional radii to apply against the border. All radii must be specified in absolute dimensions. Relative dimensions are not supported. Setting the border radii on a Frame does not clip the children of the frame.

The borderRadius property lets you set this value for all corners one time. You can override borderRadius for each corner of theFrame separately:

  • borderBottomLeftRadius
  • borderBottomRightRadius
  • borderTopLeftRadius
  • borderTopRightRadius

borderColor

The color of the border. Because the contents of a Frame are resized when the borderWidth changes (due to a style being applied), the borderWidth is frequently kept constant and the borderColor set to transparent (or backgroundColor) if a style needs to temporarily hide the border.

borderStrokeWidth

The width of the drawn border around the Frame. When not specified, borderStrokeWidth defaults to the specified borderWidth. When specified, the actual width of the drawn border is the smaller value of the borderStrokeWidth and borderWidth. You can't draw a border outside of the border width.

Set this property separately from borderWidth when you want to vary the width of the drawn border without re-laying out the positions of components in their parent. For example, assume you set borderWidth to 10 and borderStrokeWidth to 5. The component displays with a five-pixel border, but occupies enough space on the viewport for a ten-pixel border. When you change borderStrokeWidth to 10, the component displays with a ten-pixel border without changing the amount of space the component occupies.

In contrast, if you use borderWidth on its own and change it from 5 to 10, the components displayed on the screen shift to accommodate the larger border.

borderWidth

The width of the border. Specify the border width in absolute dimensions. Relative dimensions are not supported. The border width doesn't affect the padding of the component. A drawn border is considered to be a background for the component and does not affect how the component is sized or positions its children.

item, items

The child component or layout. If more than one child is supplied, only the first one selected by the when property will be used.

Sample Frame

This example creates a 50 x 50 dp circle with a grey background and the text item centered in the circle.

{
  "type": "Frame",
  "borderRadius": 25,
  "width": "50",
  "height": "50",  
  "backgroundColor": "grey",
  "item": {
    "type": "Text",
    "text": "2",
    "width": "50",
    "height": "50",
    "textAlign": "center",
    "textAlignVertical": "center"
  }
}

Was this page helpful?

Last updated: Nov 28, 2023