Tabs导航页签栏如何根据Tabbar数均匀设置宽度
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可以通过设置TabBar布局模式枚举中的BarMode.Fixed来动态均分Tab导航栏宽度，示例代码如下：

@Entry
@Component
struct Index {
  @State fontColor: string = '#182431'
  @State selectedFontColor: string = '#007DFF'
  @State currentIndex: number = 0
  @State selectedIndex: number = 0
  private controller: TabsController = new TabsController()

  @Builder
  TabBuilder(index: number, name: string) {
    Column() {
      Text(name)
        .fontColor(this.selectedIndex === index ? this.selectedFontColor : this.fontColor)
        .fontSize(16)
        .fontWeight(this.selectedIndex === index ? 500 : 400)
        .lineHeight(22)
        .margin({ top: 17, bottom: 7 })
    }.width('100%')
  }

  build() {
    Column() {
      Tabs({ barPosition: BarPosition.Start, index: this.currentIndex, controller: this.controller }) {
        TabContent() {
          Column().width('100%').height('100%').backgroundColor('#FFBF00')
        }.tabBar(this.TabBuilder(0, 'green'))

        TabContent() {
          Column().width('100%').height('100%').backgroundColor('#007DFF')
        }.tabBar(this.TabBuilder(1, 'blue'))

        TabContent() {
          Column().width('100%').height('100%').backgroundColor('#FFBF00')
        }.tabBar(this.TabBuilder(2, 'yellow'))

        TabContent() {
          Column().width('100%').height('100%').backgroundColor('#E67C92')
        }.tabBar(this.TabBuilder(3, 'pink'))
      }
      .vertical(false)
      .barMode(BarMode.Fixed)
      .barWidth(360)
      .barHeight(56)
      .animationDuration(400)
      .onChange((index: number) => {
      _  // currentIndex controls TabContent to display tabs_
        this.currentIndex = index
        this.selectedIndex = index
      })
      .onAnimationStart((index: number, targetIndex: number, event: TabsAnimationEvent) => {
        if (index === targetIndex) {
          return
        }
       _ // selectedIndex controls the color switching between Image and Text within the custom TabBar_
        this.selectedIndex = targetIndex
      })
      .width(360)
      .height(296)
      .margin({ top: 52 })
      .backgroundColor('#F1F3F5')
    }
    .width('100%')
  }
}