Delegate agreement, keyboard off, and open

First, the commission agreement

A delegate protocol is a design pattern, and some controls (Uitextfielddelegate and Uitextviewdelegate) define the delegate protocol at the same time, UIButton No, More complex control UITableView not only have the trust protocol and the data source protocol, generally we will implement the Trust protocol in the view Controller.

Second, the keyboard open and close

First Responder, iOS event processing, the "response chain" concept, TextField and TextView called the first Responder's manifestation is the pop-up keyboard, the expression of giving up first responders is to turn off the keyboard, by: Resignfirstresponder.

Third, turn off and turn on the keyboard notification

iOS system issued, keyboard off notification uikeyboarddidnotification, keyboard open notification uikeyboarddidshownotification

Often have interface switching, notification registration and logoff put to, Viewwillappear and Viewwilldisappear

Iv. type of keyboard and use of ENTER key

iOS offers 10 keyboard types,

This article is from the "Ordinary Road" blog, please be sure to keep this source http://linjohn.blog.51cto.com/1026193/1627309

Delegate agreement, keyboard off, and open