HarmonyOS struct初始化方法

以下代码为什么编译失败？

struct PageHeader1 {
  clickAction: () => void
  constructor(clickAction: () => void) {
    super()
    this.clickAction = clickAction
  }
  build() {
  }
}
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报错：

Property 'clickAction' has no initializer and is not definitely assigned in the constructor. <ArkTSCheck>
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