TextInput在聚焦时如何让光标回到起点

// xxx.ets 
@Entry 
@Component 
struct Index { 
  controller: TextInputController = new TextInputController(); 
 
  build() { 
    Column() { 
      TextInput({ controller: this.controller }) 
        .onEditChange((isEditing: boolean) => { 
          if (isEditing) { 
            setTimeout(() => { 
              this.controller.caretPosition(0); 
            }, 100); 
          } 
        }) 
    } 
  } 
}