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Just as the question's title mentions:
What's the difference between "cellForRowAtIndexPath" and "willDisplayCell: forRowAtIndexPath:"?`
I think cell configuration can be done either in cellForRowAtIndexPath or willDisplayCell: forRowAtIndexPath:"!
987
If you want to use cell outside of the UITableView override method cellForRowAt indexPath then first of all, you need to fetch the indexPath of row and then using the indexPath of that row you can get the cell of UITableView .
func tableView(UITableView, willDisplay: UITableViewCell, forRowAt: IndexPath) Tells the delegate the table view is about to draw a cell for a particular row. func tableView(UITableView, indentationLevelForRowAt: IndexPath) -> Int. Asks the delegate to return the level of indentation for a row in a given section.
You are right, cell configuration can (in theory) be done in both methods.
However, almost all UITableView have a data source which implements cellForRowAtIndexPath: (it is a required method in the protocol). On the other hand, the willDisplayCell:forRowAtIndexPath: (which is a method of the delegate, not the data source) is optional.
As configuring a cell is usually dependent on the data you want to show, cellForRowAtIndexPath: is by far the most common place to do cell configuration. (I can't even remember using willDisplayCell:forRowAtIndexPath:).
There's one notable exception: when you are using a storyboard and static cells (instead of cell prototypes), you can't do anything useful in cellForRowAtIndexPath: (because dequeueReusableCellWithIdentifier: returns nil), so you have to do configuration in willDisplayCell:forRowAtIndexPath:, viewWillAppear: or other methods.
@NSDeveloper: you're right. Thanks for the hint.
187
cellForRowAtIndexPath should actually return a cell instance. It should be a re-used cell, when possible. This method is required for the UITableViewDataSource Protocol. This is normally where you select the data that will be displayed in the cell. With dynamic cells, it's common to set UI properties such as selected state at the same time you set the data here.
willDisplayCell is optional and is called after. This is your last chance to customize the cell before it's displayed. At this point, the cell instance has already been created. You can change things like selected state, etc. here. You should not be changing the data/structure of the cell or instantiating anything new, but only changing the state of UI properties for the cell. This is commonly used with static cells.
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