Why is the UMLableViewCell textLabel property optional?

Question

A UITableViewCell detailTextLabel must be optional , which is documented , but why is the property textLabeloptional?

Answer 1

Short answer: resource conservation. The textLabel property is optional to allow UILabel to initialize lazily. In other words, a property remains zero unless you are actually trying to access it.

You can verify this in the debugger by examining an instance of your UITableViewCell:

let cell = dequeueReusableCellWithIdentifier(MyCell.cellIdentifier, forIndexPath: indexPath) as! MyCell

// check cell.textLabel here in the debugger. should be nil.

cell.textLabel.text = "test"   // creates textLabel via lazy initialization 

Answer 2

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