Android 1.6: “android.view.WindowManager$BadTokenException: Unable to add window — token null is not for an application”

Question

I\'m trying to open a dialog window, but every time I try to open it it throws this exception:

Uncaught handler: thread main exiting due to uncaught exceptio         


        

Answer 1

Try to reset dialog window's type to

WindowManager.LayoutParams.TYPE_SYSTEM_ALERT:
dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);

Don't forget to use the permission android.permission.SYSTEM_ALERT_WINDOW

Answer 2

You cannot display an application window/dialog through a Context that is not an Activity. Try passing a valid activity reference

Answer 3

Don't use getApplicationContext() on declaring dialouge

Always use this or your activity.this

Answer 4

Instead of : Context appContext = this.getApplicationContext(); you should use a pointer to the activity you're in (probably this).

I got bitten by this today too, the annoying part is the getApplicationContext() is verbatim from developer.android.com :(

Answer 5

Just change it into

AlertDialog.Builder alert_Categoryitem = 
    new AlertDialog.Builder(YourActivity.this);

Instead of

AlertDialog.Builder alert_Categoryitem = 
    new AlertDialog.Builder(getApplicationContext());

Answer 6

Ditto on the getApplicationContext thing.

The documents on the android site says to use it, but it doesn't work...grrrrr :-P

Just do:

dialog = new Dialog(this); 

"this" is usually your Activity from which you start the dialog.