问题
In my app I want to let the user hide or show the Navigation Bar (back, home, menu). The System Bar (battery, wifi, notifications) should always be hidden.
I hide the System Bar with this code:
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
requestWindowFeature(Window.FEATURE_NO_TITLE);
And I am successfully hiding the Navigation Bar with these flags:
final static int flagsHide = 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;
But I haven't found on how to show the Navigation Bar again. Can I do that with flags or do I need something else? The System Bar has to stay invisible.
回答1:
Use this flags for showing it again
SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN |
SYSTEM_UI_FLAG_LAYOUT_STABLE
回答2:
Full full screen mode
activity.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 |
View.SYSTEM_UI_FLAG_FULLSCREEN | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
Restore
activity.getWindow()
.getDecorView()
.setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
回答3:
A solution of mine.
private void hideNavigationBar() {
// set navigation bar status, remember to disable "setNavigationBarTintEnabled"
final int flags = 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_IMMERSIVE_STICKY;
// This work only for android 4.4+
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
getWindow().getDecorView().setSystemUiVisibility(flags);
// Code below is to handle presses of Volume up or Volume down.
// Without this, after pressing volume buttons, the navigation bar will
// show up and won't hide
final View decorView = getWindow().getDecorView();
decorView.setOnSystemUiVisibilityChangeListener(new View.OnSystemUiVisibilityChangeListener() {
@Override
public void onSystemUiVisibilityChange(int visibility) {
if((visibility & View.SYSTEM_UI_FLAG_FULLSCREEN) == 0) {
decorView.setSystemUiVisibility(flags);
}
}
});
}
}
private void showNavigationBar() {
// set navigation bar status, remember to disable "setNavigationBarTintEnabled"
final int flags = View.SYSTEM_UI_FLAG_LAYOUT_STABLE
| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
// This work only for android 4.4+
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
getWindow().getDecorView().setSystemUiVisibility(flags);
// Code below is to handle presses of Volume up or Volume down.
// Without this, after pressing volume buttons, the navigation bar will
// show up and won't hide
final View decorView = getWindow().getDecorView();
decorView.setOnSystemUiVisibilityChangeListener(new View.OnSystemUiVisibilityChangeListener() {
@Override
public void onSystemUiVisibilityChange(int visibility) {
if((visibility & View.SYSTEM_UI_FLAG_FULLSCREEN) == 0) {
decorView.setSystemUiVisibility(flags);
}
}
});
}
}
The difference is removing "View.SYSTEM_UI_FLAG_HIDE_NAVIGATION"
.
回答4:
The best solution is used in all my projects
public final class SystemUIUtil {
public static void hideDefaultControls(@NonNull final Activity activity) {
final Window window = activity.getWindow();
if (window == null) {
return;
}
window.clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
window.addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
final View decorView = window.getDecorView();
if (decorView != null) {
int uiOptions = decorView.getSystemUiVisibility();
if (Build.VERSION.SDK_INT >= 14) {
uiOptions |= View.SYSTEM_UI_FLAG_LOW_PROFILE;
}
if (Build.VERSION.SDK_INT >= 16) {
uiOptions |= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
}
if (Build.VERSION.SDK_INT >= 19) {
uiOptions |= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
}
decorView.setSystemUiVisibility(uiOptions);
}
}
public static void showDefaultControls(@NonNull final Activity activity) {
final Window window = activity.getWindow();
if (window == null) {
return;
}
window.clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
window.addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
final View decorView = window.getDecorView();
if (decorView != null) {
int uiOptions = decorView.getSystemUiVisibility();
if (Build.VERSION.SDK_INT >= 14) {
uiOptions &= ~View.SYSTEM_UI_FLAG_LOW_PROFILE;
}
if (Build.VERSION.SDK_INT >= 16) {
uiOptions &= ~View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
}
if (Build.VERSION.SDK_INT >= 19) {
uiOptions &= ~View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
}
decorView.setSystemUiVisibility(uiOptions);
}
}
}
回答5:
This will help to show navigation bar:-
private void showSystemUI() {
mDecorView.setSystemUiVisibility(
View.SYSTEM_UI_FLAG_LAYOUT_STABLE
| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
}
mDecorView is your parent layout. Refer to this link for more details https://developer.android.com/training/system-ui/immersive.html
来源:https://stackoverflow.com/questions/28534080/show-navigation-bar-on-android-kitkat-after-hiding-it