如何监听当前屏幕的横竖屏状态？如何实现页面跟随屏幕横竖屏自动旋转
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应用可以使用 display.on 监听屏幕状态的变化。

页面跟随屏幕旋转的方法如下：

1、Ability级别配置：在模块配置文件module.json5中配置abilities的orientation属性"。

2、动态设置窗口方向：使用 window.setPreferredOrientation。

import { window, display } from '@kit.ArkUI';

const TAG = 'ScreenTest'
const ORIENTATION: Array<string> = \['Portrait', 'Landscape', 'Reverse Portrait', 'Reverse Landscape'\]

@Entry
@Component
struct ScreenTest {
  context = this.getUIContext();
  @State rotation: number = 0
  @State message: string = ORIENTATION\[this.rotation\]

  aboutToAppear() {
    this.setOrientation()

    let callback = async () => {
      _// ..._
    }
    try {
      display.on("change", callback); _// Listen for screen state changes_
    } catch (exception) {
      console.error(TAG, 'Failed to register callback. Code: ' + JSON.stringify(exception));
    }
  }

  setOrientation() {
    try {
      window.getLastWindow(this.context.getHostContext(), (err, data) => { _// 获取window实例_
        if (err.code) {
          console.error(TAG, 'Failed to obtain the top window. Cause: ' + JSON.stringify(err));
          return;
        }
        let windowClass = data;
        console.info(TAG, 'Succeeded in obtaining the top window. Data: ' + JSON.stringify(data));

        let orientation = window.Orientation.AUTO\_ROTATION; _// 设置窗口方向为传感器自动旋转模式。_
        try {
          windowClass.setPreferredOrientation(orientation, (err) => {
            if (err.code) {
              console.error(TAG, 'Failed to set window orientation. Cause: ' + JSON.stringify(err));
              return;
            }
            console.info(TAG, 'Succeeded in setting window orientation.');
          });
        } catch (exception) {
          console.error(TAG, 'Failed to set window orientation. Cause: ' + JSON.stringify(exception));
        }
        ;
      });
    } catch (exception) {
      console.error(TAG, 'Failed to obtain the top window. Cause: ' + JSON.stringify(exception));
    }
    ;
  }

  build() {
    Row() {
      Column() {
        Text(\`${this.rotation}\`).fontSize(25)
        Text(\`${this.message}\`).fontSize(25)
      }
      .width("100%")
    }
    .height("100%")
  }
}

**参考链接**

[display.on](https://developer.huawei.com/consumer/cn/doc/harmonyos-references/js-apis-display#displayonaddremovechange)、[设置窗口的显示方向属性](https://developer.huawei.com/consumer/cn/doc/harmonyos-references/arkts-apis-window-window#setpreferredorientation9)