How to call getWindow() outside an Activity in Android?

懵懂的女人 提交于 2019-11-27 02:02:29


I am trying to organize my code and move repetitive functions to a single class. This line of code works fine inside a class that extends activity:

getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);

However it is not working when I try to include it into an external class.

How do I call getWindow() from another class to apply it inside an Activity?


Pass a reference of the activity when you create the class, and when calling relevant methods and use it.

void someMethodThatUsesActivity(Activity myActivityReference) {
    myActivityReference.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);


You shall not keep references around as suggested in the accepted answer. This works, but may cause memory leaks.

Use this instead from your view:

((Activity) getContext()).getWindow()...

You have a managed reference to your activity in your view, which you can retrieve using getContext(). Cast it to Activity and use any methods from the activity, such as getWindow().


You can use following method to cast current context to activity:

 * Get activity instance from desired context.
public static Activity getActivity(Context context) {
    if (context == null) return null;
    if (context instanceof Activity) return (Activity) context;
    if (context instanceof ContextWrapper) return getActivity(((ContextWrapper)context).getBaseContext());
    return null;

Then you can get window from the activity.




It's will be easier