TextInput组件如何清空输入框内输入的内容

struct Index {  
  @State text: string = 'Hello World'  
  controller: TextInputController = new TextInputController()  
  build() {  
    Row() {  
      Column() {  
        TextInput({ placeholder: 'Please input your words.', text: this.text,  
          controller:this.controller}).onChange((value) => {  
          this.text = value  
        })  
        Button("Clear TextInput").onClick(() => {  
          this.text = "";  
        })  
      }  
      .width('100%')  
    }  
    .height('100%')  
  }  
}