沉浸式隐藏系统 状态栏/导航栏。 参考官方文档 Hide system bars for immersive mode (opens new window)

val windowInsetsController =
        WindowCompat.getInsetsController(window, window.decorView)
// Configure the behavior of the hidden system bars.
windowInsetsController.systemBarsBehavior =
    WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE

// Add a listener to update the behavior of the toggle fullscreen button when
// the system bars are hidden or revealed.
ViewCompat.setOnApplyWindowInsetsListener(window.decorView) { view, windowInsets ->
    // You can hide the caption bar even when the other system bars are visible.
    // To account for this, explicitly check the visibility of navigationBars()
    // and statusBars() rather than checking the visibility of systemBars().
    if (windowInsets.isVisible(WindowInsetsCompat.Type.navigationBars())
        || windowInsets.isVisible(WindowInsetsCompat.Type.statusBars())) {
        binding.toggleFullscreenButton.setOnClickListener {
            // Hide both the status bar and the navigation bar.
            windowInsetsController.hide(WindowInsetsCompat.Type.systemBars())
        }
    } else {
        binding.toggleFullscreenButton.setOnClickListener {
            // Show both the status bar and the navigation bar.
            windowInsetsController.show(WindowInsetsCompat.Type.systemBars())
        }
    }
    ViewCompat.onApplyWindowInsets(view, windowInsets)
}