Cocoa touch(八):UIAlertView
@interface UIAlertView : UIView - (id)initWithTitle:(NSString *)title message:(NSString *)message delegate:(id /*<UIAlertViewDelegate>*/)delegate cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles, ... NS_REQUIRES_NIL_TERMINATION; @property(nonatomic,assign) id/*<UIAlertViewDelegate>*/ delegate; // weak reference @property(nonatomic,copy) NSString *title; @property(nonatomic,copy) NSString *message; // secondary explanation text - (NSInteger)addButtonWithTitle:(NSString *)title; // returns index of button. 0 based. - (NSString *)buttonTitleAtIndex:(NSInteger)buttonIndex; @property(nonatomic,readonly) NSInteger numberOfButtons; @property(nonatomic) NSInteger cancelButtonIndex; // if the delegate does not implement -alertViewCancel:, we pretend this button was clicked on. default is -1 @property(nonatomic,readonly) NSInteger firstOtherButtonIndex;// -1 if no otherButtonTitles or initWithTitle:... not used @property(nonatomic,readonly,getter=isVisible) BOOL visible; // shows popup alert animated. - (void)show; // hides alert sheet or popup. use this method when you need to explicitly dismiss the alert. // it does not need to be called if the user presses on a button - (void)dismissWithClickedButtonIndex:(NSInteger)buttonIndex animated:(BOOL)animated; // Alert view style - defaults to UIAlertViewStyleDefault @property(nonatomic,assign) UIAlertViewStyle alertViewStyle NS_AVAILABLE_IOS(5_0); /* Retrieve a text field at an index - raises NSRangeException when textFieldIndex is out-of-bounds. The field at index 0 will be the first text field (the single field or the login field), the field at index 1 will be the password field. */ - (UITextField *)textFieldAtIndex:(NSInteger)textFieldIndex NS_AVAILABLE_IOS(5_0); @end
@protocol UIAlertViewDelegate <NSObject> @optional // Called when a button is clicked. The view will be automatically dismissed after this call returns - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex; // Called when we cancel a view (eg. the user clicks the Home button). This is not called when the user clicks the cancel button. // If not defined in the delegate, we simulate a click in the cancel button - (void)alertViewCancel:(UIAlertView *)alertView; - (void)willPresentAlertView:(UIAlertView *)alertView; // before animation and showing view - (void)didPresentAlertView:(UIAlertView *)alertView; // after animation - (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex; // before animation and hiding view - (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex; // after animation // Called after edits in any of the default fields added by the style - (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView; @end
UIAlertView *alertView = [UIAlertView alloc] initWithTitle: @"Hello world" message: @"Do you agree" delete: self cacelButtonTitle: @"Cancel" otherButtonTitles: @"NO", @"YES", nil]; alertView.alertViewStyle = NSAlertViewStyleDefault; [alertView show];
typedef NS_ENUM(NSInteger, UIAlertViewStyle) { UIAlertViewStyleDefault = 0, UIAlertViewStyleSecureTextInput, UIAlertViewStylePlainTextInput, UIAlertViewStyleLoginAndPasswordInput };