Android - NullPointerException when calling sendBroadcast(intent)

I am trying to display the options menu when a list item is checked in my app. I am doing this by broadcasting an intent when the checkbox is clicked via a listener and a helper class that开发者_StackOverflow社区 extends Activity. My code for the helper class is:

public class menuHelper extends Activity{

    private void showMenu(int checked){

        try{
            Intent intent = new Intent(SHOW_MENU);
            intent.putExtra("check", checked);
            sendBroadcast(intent);
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
}

The problem is when the sendBroadcast method is invoked. An exception is thrown and the stack trace states that it is a NullPointerException at sendBroadcast(intent). As far as I can tell, the intent is not null, but I am missing something here because the exception is thrown.

It appears that calling the sendBroadcast() method from within an adapter (regardless of using a subclass extending Activity to do so) is simply illegal.

To implement my desired functionality I found that if you inject the calling activity into the adapter class and call a method from the activity to display (or hide) the options menu this null pointer error does not occur and the menu displays or not beautifully.