harmony 鸿蒙Blank

2025-06-12
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Blank

The Blank component is a spacer in the layout, automatically filling the remaining space along the main axis of its parent container. It works only when the parent component is Row, Column, or Flex.

NOTE

This component is supported since API version 7. Updates will be marked with a superscript to indicate their earliest API version.

Child Components

Not supported

APIs

Blank(min?: number|string)

Since API version 10: - When the Blank component is used within a Row, Column, or Flex container, it will automatically stretch or shrink along the main axis if it does not have a main axis size specified. If the Blank component has a main axis size specified or if the container is set to adapt to the size of its child nodes, the component will not automatically stretch or shrink. - Relationship between size and min of the Blank component on the main axis: max(min, size). - If the Blank component has a cross axis size specified, it will not fill up the parent container on the cross axis. If it does not have a cross axis size specified, it will fill up the parent container on the cross axis, following the ItemAlign.Stretch mode, the default setting of alignSelf.

Widget capability: This API can be used in ArkTS widgets since API version 9.

Atomic service API: This API can be used in atomic services since API version 11.

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name	Type	Mandatory	Description
min	number \|string	No	Minimum size of the Blank component in the container along the main axis. Default value: 0 If the type is number, the default unit is vp. If the type is string, the pixel unit can be explicitly specified, for example, ‘10px’. If the unit is not specified, the default unit vp is used, in which case ‘10’ is equivalent to 10vp. NOTE This parameter cannot be set in percentage. If the value is negative, the default value is used. If the minimum size is larger than the available space of the container, it is used as the component size, and the component extends beyond the container.

Attributes

In addition to the universal attributes, the following attributes are supported.

color

color(value: ResourceColor)

Sets the color to fill the blank.

Widget capability: This API can be used in ArkTS widgets since API version 9.

Atomic service API: This API can be used in atomic services since API version 11.

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name	Type	Mandatory	Description
value	ResourceColor	Yes	Color to fill the blank. Default value: Color.Transparent

Events

The universal events are supported.

Example

Example 1: Filling Remaining Space

This example shows how the Blank component fills the remaining space in landscape and portrait modes.

// xxx.ets
@Entry
@Component
struct BlankExample {
  build() {
    Column() {
      Row() {
        Text('Bluetooth').fontSize(18)
        Blank()
        Toggle({ type: ToggleType.Switch }).margin({ top: 14, bottom: 14, left: 6, right: 6 })
      }.width('100%').backgroundColor(0xFFFFFF).borderRadius(15).padding({ left: 12 })
    }.backgroundColor(0xEFEFEF).padding(20)
  }
}

Portrait mode

en-us_image_0000001256858407

Landscape mode

en-us_image_0000001212378418

Example 2: Filling a Fixed Width

This example shows the effect of using the min parameter of the Blank component when its parent component does not have a width set.

// xxx.ets
@Entry
@Component
struct BlankExample {
  build() {
    Column({ space: 20 }) {
      // If the width of the parent container is not set, the Blank component becomes invalid. In this case, you can set min to specify the minimum width of the Blank component.
      Row() {
        Text('Bluetooth').fontSize(18)
        Blank().color(Color.Yellow)
        Toggle({ type: ToggleType.Switch }).margin({ top: 14, bottom: 14, left: 6, right: 6 })
      }.backgroundColor(0xFFFFFF).borderRadius(15).padding({ left: 12 })

      Row() {
        Text('Bluetooth').fontSize(18)
        // Set the minimum width to 160.
        Blank('160').color(Color.Yellow)
        Toggle({ type: ToggleType.Switch }).margin({ top: 14, bottom: 14, left: 6, right: 6 })
      }.backgroundColor(0xFFFFFF).borderRadius(15).padding({ left: 12 })

    }.backgroundColor(0xEFEFEF).padding(20).width('100%')
  }
}

If the width of the parent container is not set, set min to specify the minimum width of the Blank component.

blankmin