HarmonyOS 自定义键盘弹出，输入框内容被遮挡，系统键盘是正常的，如何解决？

import window from '@ohos.window';  
@Entry  
@Component  
struct ScrollExample {  
  scroller: Scroller = new Scroller()  
  private arr: number[] = [0, 1, 2, 3, 4, 5]  
  @State scrollHeight: number = 0;  
  @State isRebuild: boolean = false;  
  @State keyHeight: number =0;  
  @State text: string = ''  
  aboutToAppear() {  
    window.getLastWindow(getContext(this)).then(currentWindow =>{  
      let property = currentWindow.getWindowProperties();  
      // init window height  
      let avoidArea = currentWindow.getWindowAvoidArea(window.AvoidAreaType.TYPE_KEYBOARD);  
      this.scrollHeight = px2vp(property.windowRect.height - avoidArea.bottomRect.height);  
      // monitor the hiding and display of softKeyboard  
      currentWindow.on('avoidAreaChange', async data => {  
        if (data.type !== window.AvoidAreaType.TYPE_KEYBOARD) {  
          this.keyHeight=avoidArea.bottomRect.height;  
          return;  
        }  
        this.scrollHeight = px2vp(property.windowRect.height - data.area.bottomRect.height);  
      })  
    })  
  }  
  build() {  
    Stack({ alignContent: Alignment.TopStart }) {  
      Column() {  
        Scroll(this.scroller) {  
          Column() {  
            TextInput({ text: this.text, placeholder: 'input your word...' })  
              .placeholderFont({ size: 14, weight: 400 })  
              .width(320)  
              .height(40).margin(200)  
              .fontSize(14)  
              .fontColor(Color.Black)  
              .backgroundColor(Color.White)  
            ForEach(this.arr, (item:number) => {  
              Text(item.toString())  
                .width('90%')  
                .height(150)  
                .backgroundColor(0xFFFFFF)  
                .borderRadius(15)  
                .fontSize(16)  
                .textAlign(TextAlign.Center)  
                .margin({ top: 10 })  
            })  
          }.width('100%')  
        }  
        .width('100%').height(this.scrollHeight).layoutWeight(1)  
        Text('这是一个测试文本')  
          .width('100%')  
          .height(50)  
          .backgroundColor(Color.Red)  
          .margin({bottom: this.scrollHeight})  
      }.width('100%').height('100%').justifyContent(FlexAlign.Start)  
    }.width('100%').height('100%').backgroundColor(0xDCDCDC)  
  }  
}