HarmonyOS 鸿蒙Next：如果实现APP切到后台以及在后台查看时蒙层遮罩效果

在EntryAbility中onWindowStageCreate方法中添加AppStorage.setOrCreate('windowStage',windowStage);
page重demo如下：

import { window } from '@kit.ArkUI';
@Entry
@Component
struct Index {
@State message: string = ‘Hello World’;
@State flag: boolean = false
onPageShow(): void {
let windowStage = AppStorage.get(“windowStage”) as window.WindowStage;
windowStage.on(“windowStageEvent”, (data) => {
if (data === window.WindowStageEventType.PAUSED) {
this.flag = true
}
else {
this.flag = false
}
})
}
build() {
Row() {
Column() {
Text(this.message)
.fontSize(50)
.fontWeight(FontWeight.Bold)
}
.width(‘100%’)
}
.height(‘100%’)
.foregroundBlurStyle(this.flag ? BlurStyle.Thin : BlurStyle.NONE, {
colorMode: ThemeColorMode.LIGHT,
adaptiveColor: AdaptiveColor.DEFAULT
})
}
}