Android: Base activity

Base activity

public class BaseActivity extends FragmentActivity{

 private Dialog loadingDialog;

 protected List<AsyncTask> tasks;
 protected List<Toast> toasts;

 @Override
 protected void onCreate(Bundle savedInstanceState) {

  super.onCreate(savedInstanceState);

  tasks = new LinkedList<AsyncTask>();
  toasts = new LinkedList<Toast>();
}

 @Override
 protected void onPause() {

  super.onPause();

  isVisible = false;

  this.hideLoadingDialog();

  this.cancelAllTasks();

  this.cancelAllToasts();
 }

 private void cancelAllToasts() {

  for (Toast currentToast : toasts) {
   currentToast.cancel();
  }

  toasts.clear();
 }

 public void addTask(AsyncTask task) {

  tasks.add(task);
 }

 private void cancelAllTasks() {

  for (AsyncTask currentTask : tasks) {

   if (currentTask != null && currentTask.getStatus() != Status.FINISHED) {
    currentTask.cancel(true);
   }
  }

  tasks.clear();
 }

 @Override
 public void showLoadingDialog() {

  if (loadingDialog == null) {

  // Probably should have a reference counter here
   loadingDialog = DialogHelper.buildLoadingDialog(this, this.getString(R.string.loading_dialog_loading_message));

   loadingDialog.show();
  }
 }

 @Override
 public void hideLoadingDialog() {

  if (loadingDialog != null) {

  // And here we decrement that counter and dismiss the dialog if it reaches 0
   loadingDialog.dismiss();
   loadingDialog = null;
  }
 }
 
 @Override
 public void onDestroy() {

  super.onDestroy();

  MemoryManagementHelper.unbindDrawables(((ViewGroup) findViewById(android.R.id.content)).getChildAt(0));
  System.gc();
 }

}

MemoryManagementHelper

public class MemoryManagementHelper {

 public static void unbindDrawables(View view) {
  if (view != null) {
         if (view.getBackground() != null) {
          view.getBackground().setCallback(null);
         }
         
         if (view instanceof ViewGroup && !(view instanceof AdapterView)) {
             for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
              unbindDrawables(((ViewGroup) view).getChildAt(i));
             }
             ((ViewGroup) view).removeAllViews();
         }
  } else {
   // TODO - ?
  }
    }
}