将 android 之前活动中的 activity 最小化

Question

我正在开发一个支持即时消息的视频通话组件。我想在消息 activity 中添加按下后退时最小化视频通话屏幕的选项和 return 以同时执行这两项操作（类似 WhatsApp 的功能）。问题是，我找不到解决方案，因为返回到上一个 activity 将完成当前的。那么我如何 override 我的 onBackpressed() 才能最小化而不是完成通话屏幕 activity （假设将其添加到通知）和 return 到消息传递 activity?

Answer 1

你想做的事情叫做Picture-in-Picture。

Android 8.0 (API level 26) allows activities to launch in picture-in-picture (PIP) mode. PIP is a special type of multi-window mode mostly used for video playback. It lets the user watch a video in a small window pinned to a corner of the screen while navigating between apps or browsing content on the main screen.

一个非常简单的例子：

1) 在您的 AndroidManifest 文件中指定 activity 支持 PIP：

<activity
      android:name=".VideoActivity"
      android:configChanges="screenSize|smallestScreenSize|screenLayout|orientation"
      android:resizeableActivity="true"
      android:supportsPictureInPicture="true"/>

2) 触发 PIP 模式以响应某些用户操作，例如 onBackPressed():

override fun onBackPressed() {
   // Ideally you would want to enter PIP while a video is playing, so:
   val isVideoPlaying = // have a condition here that holds true while the video is playing

   if (isVideoPlaying) {
        enterPictureInPictureMode()
   } else {
        super.onBackPressed()
   }
}

将 android 之前活动中的 activity 最小化

Minimizimg an activity in previous activities in android

android

activity-lifecycle

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