First, deep appreciation for sharing this awesome work! It is helping me tremendously in my code.
I found an issue I hope you can help. What I found was that deleting a cell immediately after programmatically move gmGridView to an object by scrollToObjectAtIndex displayed no update of the visible cells in view. Then I tried to modified Demo1ViewController.m code and I saw the same behavior.
Here is what I did: after making the delete button visible by default in each cell, I added the following lines to Demo1ViewController.m / viewWillAppear:
[_gmGridView scrollToObjectAtIndex:20 atScrollPosition:GMGridViewScrollPositionBottom animated:NO];
This causes the A16-A21 cells to show up in view, then after I tapped the delete button in a cell, say A18 and after click @"Delete" in popup alert view, the expected behavior was that A18 should be gone and A22 should move into visible view. However, the view was not updated, i.e. A16-A21 were still shown. By scrolling away and back, I could see that A18 was actually deleted. I saw [gmGridView reloadData] was called.
Thanks for your help,