"IOS" Notification listener

The following example is: Listen to the text box Accountfield content changes, when changes occur, call the TextChange method (multiple). Listener end requires removal of notifications.

-(void   //  1. Monitoring notifications  [[ Nsnotificationcenter Defaultcenter] addobserver:self selector: @selector (textchange) Name: Uitextfieldtextdidchangenotification object  : Self.accountfield];} Listener end requires removal of -(void  ) dealloc{[[ Nsnotificationcenter Defaultcenter] removeobserver:self];}  /*  * * text box changes when the text is called  */-(void   ) textchange{self.loginBtn.enabled  = (self.accountField.text.length &&  self.pwdField.text.length);  

1. addobserver:self

2. Selector: @selector (TextChange) listens to, executes the method.

3. Name:uitextfieldtextdidchangenotification enumeration type.

4. Object:self.accountField Listener Object

"IOS" Notification listener