https://developer.android.com/training/system-ui/immersive.html

活动:

@Override
public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
    if (hasFocus) {
        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);
    }
}

安卓清单：

 <activity android:name=".LoginActivity"
            android:configChanges="orientation|keyboardHidden|screenSize"
            android:label="@string/title_activity_login"
            android:theme="@style/FullscreenTheme"
            ></activity>

 protected void onCreate(Bundle savedInstanceState) {
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    super.onCreate(savedInstanceState);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_splash_screen);
    getSupportActionBar().hide();

}

提示:使用getWindow().setLayout()会搞砸你的全屏显示!注意，这个方法的文档说:

设置窗口的宽度和高度布局参数… 你可以把它们改成……用于制作非全屏窗口的绝对值。

http://developer.android.com/reference/android/view/Window.html#setLayout%28int,%20int%29

For my purposes, I found that I had to use setLayout with absolute parameters to resize my full screen window correctly. Most of the time, this worked fine. It was called by an onConfigurationChanged() event. There was a hiccup, however. If the user exited the app, changed the orientation, and reentered, it would lead to firing off my code which included setLayout(). During this re-entry time window, my status bar (which was hidden by the manifest) would be made to re-appear, but at any other time setLayout() would not cause this! The solution was to add an additional setLayout() call after the one with the hard values like so:

       public static void setSize( final int width, final int height ){
//DO SOME OTHER STUFF...
            instance_.getWindow().setLayout( width, height );
            // Prevent status bar re-appearance
            Handler delay = new Handler();
            delay.postDelayed( new Runnable(){ public void run() {
                instance_.getWindow().setLayout(
                    WindowManager.LayoutParams.FILL_PARENT,
                    WindowManager.LayoutParams.FILL_PARENT );
            }}, FILL_PARENT_ON_RESIZE_DELAY_MILLIS );
        }

然后，窗口正确地调整大小，状态栏不会重新出现，不管触发这一事件。

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);
    }

 @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);
    }
}

小心

requestWindowFeature(Window.FEATURE_NO_TITLE);

如果您正在使用任何方法设置操作栏如下:

getSupportActionBar().setHomeButtonEnabled(true);

它将导致一个空指针异常。