Fixed a null pointer exception in task actions loader

astrid/src/com/todoroo/astrid/adapter/TaskAdapter.java

@@ -734,6 +734,7 @@ public class TaskAdapter extends CursorAdapter implements Filterable {
                     Task.MODIFICATION_DATE, Task.COMPLETION_DATE);
 
             final Activity activity = fragment.getActivity();
+            if (activity != null) {
                 activity.runOnUiThread(new Runnable() {
                     @Override
                     public void run() {
@@ -762,6 +763,7 @@ public class TaskAdapter extends CursorAdapter implements Filterable {
                 });
             }
         }
+    }
 
     /**
      * Add detail to a task