Animating custom-drawn UITableViewCell when entering edit mode
- by Adam Alexander
Background
First of all, much gratitude to atebits for their very informative blog post Fast Scrolling in Tweetie with UITableView. The post explains in detail how the developers were able to squeeze as much scrolling performance as possible out of the UITableViews in Tweetie.
Goals
Beginning with the source code linked from the blog post (original) (my github repo):
Allow a UITableView using these custom cells to switch to edit mode, exposing the UI for deleting an item from the table. (github commit)
Move the cell's text aside as the deletion control slides in from the left. This is complete, although the text jumps back and forth without animation. (github commit)
Apply animation to the text movement in goal 2 above for a smooth user experience. This is the step where I became stuck.
The Question
What is the best way to introduce this animation to complete goal 3? It would be nice if this could be done in a manner that keeps the logic from my last commit because I would love the option to move the conflicting part of the view only, while any non-conflicting portions (such as right-justified text) stay in the same place or move a different number of pixels. If the above is not possible then undoing my last commit and replacing it with an option that slides the entire view to the right would be a workable solution also.
I appreciate any help anyone can provide, from quick pointers and ideas all the way to code snippets or github commits. Of course you are welcome to fork my repo if you would like. I will be staying involved with this question to make sure any successful resolution is committed to github and fully documented here. Thanks very much for your time!
Updated thoughts
I have been thinking about this a lot since my first post and realized that moving some text items relative to others in the view could undo some of the original performance goals solved in the original blog post. So at this point I am thinking a solution where the entire single subview is animated to its new postion may be the best one.
Second, if it is done in this way there may be an instance where the subview has a custom color or gradient background. Hopefully this can be done in a way that in its normal position the background extends unseen off to the left enough so that when the view is slid to the right the custom background is still visible across the entire cell.
