Auto Layout for Table View Cells with Dynamic Heights

This is the sample application for the blog post Auto Layout for Table View Cells with Dynamic Heights which implements a Twitter-like table view that can switch between two cell types:

• JSManualMessageCell uses manual geometry to position elements in layoutSubviews
• JSAutoMessageCell uses Auto Layout to position elements with constraints

The table view also implements 3 performance optimizations that can be turned on and off with compile-time feature flags:

1. row height caching (PERFORMANCE_ENABLE_HEIGHT_CACHE)
2. separate cell identifier for media cells (PERFORMANCE_ENABLE_MEDIA_CELL_ID)
3. iOS 7's tableView:estimatedHeightForRowAtIndexPath: (PERFORMANCE_ENABLE_ESTIMATED_ROW_HEIGHT)

Screenshot: