harmony 鸿蒙stateStyles: Polymorphic Style

2025-06-12
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stateStyles: Polymorphic Style

Unlike \@Styles, which are used to reuse styles only on static pages, stateStyles enables you to set state-specific styles.

NOTE

Polymorphic style supports only universal attributes. If the polymorphic style does not take effect, the attribute may be a private attribute of the component, for example, fontColor or backgroundColor of the TextInput component. In this case, you can use attributeModifier to dynamically set component attributes to enable the polymorphic style.

Overview

stateStyles is an attribute method that sets the style based on the internal state of a component. It is similar to a CSS pseudo-class, with different syntax. ArkUI provides the following states:

focused
normal
pressed
disabled
selected¹⁰⁺

NOTE

Currently, only the Tab button and arrow buttons on the external keyboard can be used to trigger the focused state. Sequential keyboard navigation is not supported for nested scrollable components.

Use Scenarios

Common Scenarios

This example shows the most basic application scenario of stateStyles. Button1 is the first component and Button2 the second component. When the component is pressed, the black style specified for pressed takes effect. When the Tab key is pressed for sequential navigation, Button1 obtains focus first and is displayed in the pink style specified for focus. When Button 2 is focused, it is displayed in the pink style specified for focus, and Button1 changes to the blue style specified for normal.

@Entry
@Component
struct StateStylesSample {
  build() {
    Column() {
      Button('Button1')
        .stateStyles({
          focused: {
            .backgroundColor('#ffffeef0')
          },
          pressed: {
            .backgroundColor('#ff707070')
          },
          normal: {
            .backgroundColor('#ff2787d9')
          }
        })
        .margin(20)
      Button('Button2')
        .stateStyles({
          focused: {
            .backgroundColor('#ffffeef0')
          },
          pressed: {
            .backgroundColor('#ff707070')
          },
          normal: {
            .backgroundColor('#ff2787d9')
          }
        })
    }.margin('30%')
  }
}

Figure 1 Focused and pressed states

Video_2023-03-17_120758

Combined Use of \@Styles and stateStyles

The following example uses \@Styles to specify different states of stateStyles.

@Entry
@Component
struct MyComponent {
  @Styles normalStyle() {
    .backgroundColor(Color.Gray)
  }

  @Styles pressedStyle() {
    .backgroundColor(Color.Red)
  }

  build() {
    Column() {
      Text('Text1')
        .fontSize(50)
        .fontColor(Color.White)
        .stateStyles({
          normal: this.normalStyle,
          pressed: this.pressedStyle,
        })
    }
  }
}

Figure 2 Normal and pressed states

Video_2023-03-17_144824

Using Regular Variables and State Variables in stateStyles

stateStyles can use this to bind regular variables and state variables in a component.

@Entry
@Component
struct CompWithInlineStateStyles {
  @State focusedColor: Color = Color.Red;
  normalColor: Color = Color.Green

  build() {
    Column() {
      Button('clickMe').height(100).width(100)
        .stateStyles({
          normal: {
            .backgroundColor(this.normalColor)
          },
          focused: {
            .backgroundColor(this.focusedColor)
          }
        })
        .onClick(() => {
          this.focusedColor = Color.Pink
        })
        .margin('30%')
    }
  }
}

By default, the button is displayed in green in the normal state. When you press the Tab key for the first time, the button obtains focus and is displayed in the red style specified for focus. After a click event occurs and you press the Tab key again, the button obtains focus and changes to the pink style.

Figure 3 Change of the styles in focused state by a click

Video_2023-03-17_144605