harmony 鸿蒙Z-order Control

2025-06-12
浏览 (3)

Z-order Control

The zIndex attribute sets the z-order of a component in the stacking context.

NOTE

The APIs of this module are supported since API version 7. Updates will be marked with a superscript to indicate their earliest API version.

zIndex

zIndex(value: number)

Sets the stack level of the component.

Widget capability: Since API version 9, this feature is supported in ArkTS widgets.

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	number	Yes	Stacking order of the component relative to its sibling components in a container. The components with a larger z-index value cover those with a smaller one. When dynamically changing zIndex does not involve adding or removing sibling nodes, the components are sorted stably based on their previous stack level.

Example

Example 1: Setting the Component Stacking Order

This example demonstrates how to set the stacking order of components using zIndex.

// xxx.ets
@Entry
@Component
struct ZIndexExample {
  build() {
    Column() {
      Stack() {
        // Components are stacked. By default, the component defined later is on the top. A component with a larger zIndex value is displayed before one with a smaller zIndex value.
        Text('1, zIndex(2)')
          .size({ width: '40%', height: '30%' }).backgroundColor(0xbbb2cb)
          .zIndex(2)
        Text('2, default zIndex(1)')
          .size({ width: '70%', height: '50%' }).backgroundColor(0xd2cab3).align(Alignment.TopStart)
          .zIndex(1)
        Text('3, zIndex(0)')
          .size({ width: '90%', height: '80%' }).backgroundColor(0xc1cbac).align(Alignment.TopStart)
      }.width('100%').height(200)
    }.width('100%').height(200)
  }
}

Display of child components in the Stack component when zIndex is not set

Display of child components in the Stack component when zIndex is set

Example 2: Dynamically Modifying the zIndex Attribute

This example demonstrates dynamically modifying the zIndex attribute on a Button component.

// xxx.ets
@Entry
@Component
struct ZIndexExample {
  @State zIndex_ : number = 0
  build() {
    Column() {
      // Clicking the Button component changes the zIndex value. Components are sorted stably based on their previous stacking order.
      Button("change Text2 zIndex")
        .onClick(()=>{
          this.zIndex_ = (this.zIndex_ + 1) % 3;
        })
      Stack() {
        Text('1, zIndex(1)')
          .size({ width: '70%', height: '50%' }).backgroundColor(0xd2cab3).align(Alignment.TopStart)
          .zIndex(1)
        Text('2, default zIndex(0), now zIndex:' + this.zIndex_)
          .size({ width: '90%', height: '80%' }).backgroundColor(0xc1cbac).align(Alignment.TopStart)
          .zIndex(this.zIndex_)
      }.width('100%').height(200)
    }.width('100%').height(200)
  }
}

Effect without clicking the Button component to change zIndex