如何解决window创建的模态窗口默认焦点不在界面上，导致不响应返回事件的问题
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**问题现象**

通过window创建的窗口默认焦点不在界面上，导致不响应返回事件。

**解决措施**

模态窗口是给系统权限申请弹窗用的，默认不能响应back手势事件。使用setDialogBackGestureEnabled接口设置模态窗口是否响应手势返回事件，设置为true时，模态窗口可响应onBackPress回调。参考代码如下：

_// EntryAbility.ets_
import { UIAbility } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';
import { window } from '@kit.ArkUI';


export default class EntryAbility extends UIAbility {
  onWindowStageCreate(windowStage: window.WindowStage): void {
    console.info('onWindowStageCreate');
    let windowClass: window.Window | undefined = undefined;
    let config: window.Configuration = {
      name: "test",
      windowType: window.WindowType.TYPE\_DIALOG,
      ctx: this.context
    };
    try {
      window.createWindow(config, (err: BusinessError, data) => {
        const errCode: number = err.code;
        if (errCode) {
          console.error(\`Failed to create the window. Cause code: ${err.code}, message: ${err.message}\`);
          return;
        }
        windowClass = data;
        windowClass.setUIContent('pages/Index');
        let enabled = true;
       _ // Enable response to back gesture event_
        let promise = windowClass.setDialogBackGestureEnabled(enabled);
        promise.then(() => {
          console.info('Succeeded in setting dialog window to respond back gesture.');
        }).catch((err: BusinessError) => {
          console.error(\`Failed to set dialog window to respond back gesture. Cause code: ${err.code}, message: ${err.message}\`);
        });
      });
    } catch (exception) {
      console.error(\`Failed to create the window. Cause code: ${exception.code}, message: ${exception.message}\`);
    }
  }
}

**参考链接**

[setDialogBackGestureEnabled](https://developer.huawei.com/consumer/cn/doc/harmonyos-references/arkts-apis-window-window#setdialogbackgestureenabled12)