Android 隐藏虚拟按键

领导要求：

横屏播放视频时，不展示虚拟按键；恢复到竖屏时，展示虚拟按键；

/*** NavigationBar 显示与隐藏*/public class NavigationBarHelper {private Fragment fragment;private boolean mSystemUiVisibilityUpdated;// android 4.4 api19 及以上，记录竖屏时的SystemUiVisibilityprivate int mSystemUiVisibilityPortrait;public NavigationBarHelper(Fragment fragment) {this.fragment = fragment;}private View getDecorView() {if (fragment != null&& fragment.getActivity() != null) {return fragment.getActivity().getWindow().getDecorView();}return null;}public void beforeOrientationChange(boolean targetLandscape) {if (targetLandscape) {hideBottomMenu();} else {showBottomMenu();}}/*** 竖屏 显示虚拟按键*/private void showBottomMenu() {if (fragment != null && fragment.getActivity() != null) {View decorView = getDecorView();if (decorView != null) {if (Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB&& Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {decorView.setSystemUiVisibility(View.VISIBLE);} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT && mSystemUiVisibilityUpdated) {// 恢复 竖屏时的SystemUiVisibilitydecorView.setSystemUiVisibility(mSystemUiVisibilityPortrait);mSystemUiVisibilityUpdated = false;}}}}/*** 横屏 隐藏虚拟按键*/private void hideBottomMenu() {if (fragment != null && fragment.getActivity() != null) {View decorView = getDecorView();if (decorView != null) {if (Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB&& Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {decorView.setSystemUiVisibility(View.GONE);} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {if (mSystemUiVisibilityUpdated) {return;}// 记录竖屏时的SystemUiVisibilitymSystemUiVisibilityPortrait = decorView.getSystemUiVisibility();// 隐藏虚拟按键int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY| View.SYSTEM_UI_FLAG_FULLSCREEN;decorView.setSystemUiVisibility(uiOptions);mSystemUiVisibilityUpdated = true;}}}}/*** 退出到后台 返回时*/public void onVideoResume() {if (fragment != null && fragment.getActivity() != null) {// 当前是横屏 播放视频if (fragment.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {View decorView = getDecorView();if (decorView != null) {if (Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB&& Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {decorView.setSystemUiVisibility(View.GONE);} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {// 隐藏虚拟按键int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY| View.SYSTEM_UI_FLAG_FULLSCREEN;decorView.setSystemUiVisibility(uiOptions);}}}}}}