getWindow().addFlags(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);

主题

    <style name="Theme.FluidWallpaper.FullScreen" parent="@style/Theme.AppCompat.Light.NoActionBar">
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowTranslucentStatus">true</item>
    <item name="android:windowTranslucentNavigation">true</item>
    <item name="android:statusBarColor">@android:color/transparent</item>
    <item name="android:navigationBarColor">@android:color/transparent</item>
    <item name="android:windowLayoutInDisplayCutoutMode" tools:targetApi="o_mr1">shortEdges</item>
     </style>

安卓清单

   <activity android:exported="false"
        android:name=".FullScreenActivity"
        android:screenOrientation="fullSensor"
        android:theme="@style/Theme.FluidWallpaper.FullScreen"/>

充分沉浸:

private void askForFullScreen()
    {
        getActivity().getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION // hide nav bar
                        | View.SYSTEM_UI_FLAG_FULLSCREEN // hide status bar
                        | View.SYSTEM_UI_FLAG_IMMERSIVE);
    }

脱离完全沉浸模式:

 private void moveOutOfFullScreen() {
        getActivity().getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
    }

这些答案大部分似乎都过时了。Developer.android.com建议这样做:

科特林：

private fun hideSystemBars() {
    val windowInsetsController = ViewCompat.getWindowInsetsController(window.decorView) ?: return
    windowInsetsController.systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
    windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())
}

Java:

private void hideSystemBars() {
    WindowInsetsControllerCompat windowInsetsController = ViewCompat.getWindowInsetsController(getWindow().getDecorView());
    if (windowInsetsController == null) {
        return;
    }
    windowInsetsController.setSystemBarsBehavior(WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE);
    windowInsetsController.hide(WindowInsetsCompat.Type.systemBars());
}

更多信息:https://developer.android.com/training/system-ui/immersive

截至2022年

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
        window.decorView.windowInsetsController?.hide(WindowInsets.Type.systemBars())
    } else {
        @Suppress("DEPRECATION") // Older API support
        window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_IMMERSIVE
                or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_FULLSCREEN)
    }

使用Android Studio(当前版本是2.2.2)很容易添加一个全屏活动。

请看步骤:

右键单击你的java主包，选择“新建”，选择“活动”，然后点击“全屏活动”。

自定义活动(“活动名称”，“布局名称”等)，点击“完成”。

完成了!

现在你有一个全屏的活动很容易(查看java类和活动布局，以了解事情是如何工作的)!