Handlers and memory leaks in Android

Question

Please have a look at the code below:

public class MyGridFragment extends Fragment{          Handler myhandler = new Handler() {         @Override         public void handleMessage(Message message) {             switch (message.what) {                 case 2:                        ArrayList<HashMap<String,String>> theurls = (ArrayList<HashMap<String,String>>) message.obj;                     urls.addAll(theurls);                     theimageAdapter.notifyDataSetChanged();                     dismissBusyDialog();                     break;             }         }     } } 

When I use handler like this I get a warning "handler should be static, else it is prone to memory leaks." Can someone tell me what is the best way to do this?

Answer 1

I recently updated something similar in my own code. I just made the anonymous Handler class a protected inner class and the Lint warning went away. See if something like the below code will work for you:

public class MyGridFragment extends Fragment{      static class MyInnerHandler extends Handler{         WeakReference<MyGridFragment> mFrag;          MyInnerHandler(MyGridFragment aFragment) {             mFrag = new WeakReference<MyGridFragment>(aFragment);         }          @Override         public void handleMessage(Message message) {             MyGridFragment theFrag = mFrag.get();             switch (message.what) {             case 2:                 ArrayList<HashMap<String,String>> theurls = (ArrayList<HashMap<String,String>>) message.obj;                 theFrag.urls.addAll(theurls);                 theFrag.theimageAdapter.notifyDataSetChanged();                 theFrag.dismissBusyDialog();                 break;             }//end switch         }     }     MyInnerHandler myHandler = new MyInnerHandler(this); } 

You may have to change where I put "theFrag." as I could only guess as to what those referenced.