根据安卓开发者培训

你应该做到以下几点:

科特林：

private fun hideSystemBars() {
  val windowInsetsController =
      ViewCompat.getWindowInsetsController(window.decorView) ?: return
  // Configure the behavior of the hidden system bars
  windowInsetsController.systemBarsBehavior =
      WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
  // Hide both the status bar and the navigation bar
  windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())
}

Java:

private void hideSystemBars() {
  WindowInsetsControllerCompat windowInsetsController =
      ViewCompat.getWindowInsetsController(getWindow().getDecorView());
  if (windowInsetsController == null) {
    return;
  }
  // Configure the behavior of the hidden system bars
  windowInsetsController.setSystemBarsBehavior(
      WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
  );
  // Hide both the status bar and the navigation bar
  windowInsetsController.hide(WindowInsetsCompat.Type.systemBars());
}

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"/>

如果你使用AppCompat和ActionBarActivity，那么使用这个

getSupportActionBar () hide ();

 @Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    adjustFullScreen(newConfig);
}

@Override
public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    if (hasFocus) {
        adjustFullScreen(getResources().getConfiguration());
    }
}
private void adjustFullScreen(Configuration config) {
    final View decorView = getWindow().getDecorView();
    if (config.orientation == Configuration.ORIENTATION_LANDSCAPE) {
        decorView.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
                        | View.SYSTEM_UI_FLAG_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
    } else {
        decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
    }
}

创建一个空活动，并在onCreate中添加两行。

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // full screen activity
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        getSupportActionBar().hide();

        setContentView(R.layout.activity_main);
    }
    ...
}

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