Programming iOS 4

Chapter 21. Table Views

I’m gonna ask you the three big questions. — Go ahead. — Who made you? — You did. — Who owns the biggest piece of you? — You do. — What would happen if I dropped you? — I’d go right down the drain.

—Dialogue by Garson Kanin and Ruth Gordon, Pat and Mike

A table view (UITableView) is a scrolling interface (a vertically scrolling UIScrollView, Chapter 20) for presenting a single column of rectangular cells (UITableViewCell). It is a keystone of Apple’s strategy for making the small iPhone screen useful and powerful, and has three main purposes:

Presentation of information

The cells typically contain text, which can provide the user with helpful information. The cells are usually quite small, in order to maximize the number of them that appear on the screen at once, so this information is often condensed, truncated, or otherwise simplified.

Selection

A cell can be selected by tapping. A table view can thus be used to provide the user with a column of choices. The user chooses by tapping a cell, and the app responds appropriately to that choice.

Navigation

The appropriate response to the user’s choosing a cell is often navigation to another portion of the interface. This might be done, for example, through a modal view or a navigation interface. An extremely common configuration is a master–detail interface, in which the master view is (or contains) a table view, often at the root of a navigation interface; the user taps a listing in the table to navigate ...