Programming iOS 6, 3rd Edition

Table View Selection

A table view cell has a normal state, a highlighted state (according to its highlighted property), and a selected state (according to its selected property). It is possible to change these states directly (possibly with animation, using setHighlighted:animated: or setSelected:animated:), but you don’t want to act behind the table’s back, so you are more likely to manage selection through the table view, letting the table view manage and track the state of its cells.

These two states are closely related. In particular, when a cell is selected, it propagates the highlighted state down through its subviews by setting each subview’s highlighted property if it has one. That is why a UILabel’s highlightedTextColor applies when the cell is selected. Similarly, a UIImageView (such as the cell’s imageView) can have a highlightedImage that is shown when the cell is selected, and a UIControl (such as a UIButton) takes on its highlighted state when the cell is selected.

One of the chief purposes of your table view is likely to be to let the user select a cell. This will be possible, provided you have not set the value of the table view’s allowsSelection property to NO. The user taps a normal cell, and the cell switches to its selected state. As we’ve already seen, this will usually mean that the cell is redrawn with a blue (or gray) background view, but you can change this. If the user taps an already selected cell, by default it stays selected.

Table views can permit the ...