Troubling binding manipulators outside the visualElement class

In my custom visual element class I have a manipulator like so

Code (CSharp):

1.     this.AddManipulator(_mouseHit2 = new MouseHitManipulator((() =>
2.              {
3.                  Debug.Log(_mouseHit2.IsMouseDown);
4.              })));

This works fine for both calling its callbacks and updating the manipulators public variables.


However when I try to do a similar sorta binding outside the class as in

Code (CSharp):

1.        _previewUtil.AddManipulator(_mouseHit2 = new MouseHitManipulator((() =>
2.             {
3.                 Debug.Log(_mouseHit2.IsMouseDown);
4.             })));

The callbacks being called per event work fine but the manipulators public variables do not.

I presume this has to do with why the class requires a this. before adding the AddManipulator


Something about this I assume I'm lacking to understand, is there something I'm doing wrong and or a way around this?