科特林

遵循谷歌文档，有一个简单的方法:

override fun onWindowFocusChanged(hasFocus: Boolean) {
super.onWindowFocusChanged(hasFocus)
if (hasFocus) hideSystemUI() }


private fun hideSystemUI() {
// Enables regular immersive mode.
// For "lean back" mode, remove SYSTEM_UI_FLAG_IMMERSIVE.
// Or for "sticky immersive," replace it with SYSTEM_UI_FLAG_IMMERSIVE_STICKY
window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_IMMERSIVE
        // Set the content to appear under the system bars so that the
        // content doesn't resize when the system bars hide and show.
        or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
        or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
        or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
        // Hide the nav bar and status bar
        or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
        or View.SYSTEM_UI_FLAG_FULLSCREEN)      }


// Shows the system bars by removing all the flags
// except for the ones that make the content appear under the system bars.
private fun showSystemUI() {
window.decorView.systemUiVisibility = 
(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
        or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
        or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN)       }

谷歌文档

谢谢你的回答@克里斯蒂安，我得到了错误

android.util.AndroidRuntimeException:必须调用requestFeature() 添加内容前

我用

@Override
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_login);

    -----
    -----
}

对于安卓X

1. 透明状态栏

    window?.decorView?.systemUiVisibility = (View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN)
    window.statusBarColor = Color.TRANSPARENT

2. 透明的状态栏和底部导航栏

    window.setFlags(
        WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS,
        WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
    );

3.隐藏状态栏

API 30+推荐的Compat解决方案(包括向后兼容性)

  val windowInsetsController =
      WindowCompat.getInsetsController(window, window.decorView) ?: return
  windowInsetsController.systemBarsBehavior =
      WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
  windowInsetsController.hide(WindowInsetsCompat.Type.statusBars())

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

4. 隐藏状态栏和底部导航栏

消防级别30:

SystemUiVisibility标志已弃用。请改用WindowInsetsController。

和3一样。，只需使用WindowInsetsCompat.Type.systemBars()

    val actionBar: ActionBar? = supportActionBar
        if (actionBar != null) actionBar.hide()

    val windowInsetsController =
        WindowCompat.getInsetsController(window, window.decorView) ?: return
    windowInsetsController.systemBarsBehavior =
        WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
    windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())

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

把这些代码放在哪里?

   override fun onCreate(savedInstanceState: Bundle?) {

        /*  Put above code here ..... */
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_slider)
   }

Note

我在Pixel 3A模拟器中检查了这段代码 可能自定义android操作系统不支持 set style <style name="主题。"全屏Theme.MaterialComponents.DayNight.NoActionBar“父= >

import androidx.core.view.WindowInsetsCompat.Type

fun Activity.fullscreen() {
    with(WindowInsetsControllerCompat(window, window.decorView)) {
        systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_SHOW_BARS_BY_SWIPE
        hide(Type.systemBars())
    }
}

fun Activity.exitFullscreen() {
    WindowInsetsControllerCompat(window, window.decorView).show(Type.systemBars())
}

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。

从mozilla找到解决方案，他们在这里做了一个扩展库

如果链接中断，这里是代码

/**
 * Retrieves a {@link WindowInsetsControllerCompat} for the top-level window decor view.
 */
fun Window.getWindowInsetsController(): WindowInsetsControllerCompat {
    return WindowInsetsControllerCompat(this, this.decorView)
}


/**
 * Attempts to call immersive mode using the View to hide the status bar and navigation buttons.
 * @param onWindowFocusChangeListener optional callback to ensure immersive mode is stable
 * Note that the callback reference should be kept by the caller and be used for [exitImmersiveModeIfNeeded] call.
 */
fun Activity.enterToImmersiveMode(
    onWindowFocusChangeListener: ViewTreeObserver.OnWindowFocusChangeListener? = null
) {
    window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
    window.getWindowInsetsController().apply {
        hide(WindowInsetsCompat.Type.systemBars())
        systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
    }

    // We need to make sure system bars do not become permanently visible after interactions with content
    // see https://github.com/mozilla-mobile/fenix/issues/20240
    onWindowFocusChangeListener?.let {
        window.decorView.viewTreeObserver?.addOnWindowFocusChangeListener(it)
    }
}

/**
 * Attempts to come out from immersive mode using the View.
 * @param onWindowFocusChangeListener optional callback to ensure immersive mode is stable
 * Note that the callback reference should be kept by the caller and be the same used for [enterToImmersiveMode] call.
 */
@Suppress("DEPRECATION")
fun Activity.exitImmersiveModeIfNeeded(
    onWindowFocusChangeListener: ViewTreeObserver.OnWindowFocusChangeListener? = null
) {
    if (WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON and window.attributes.flags == 0) {
        // We left immersive mode already.
        return
    }
    onWindowFocusChangeListener?.let {
        window.decorView.viewTreeObserver?.removeOnWindowFocusChangeListener(it)
    }
    window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
    window.getWindowInsetsController().apply {
        show(WindowInsetsCompat.Type.systemBars())
    }
}