学习IOS开发UI篇--UI知识点总结(一) UIButton/UITextField

　　UIkit框架下的几个基本控件,UIButton,UITextField,UILabel,UIImageView,UIScrollView,UITableView,UITableViewCell,UIPageControl;

　　他们的继承关系,UILabel,UIImageView,UIScrollView,UITableViewCell,直接继承自UIView;

　　　　　　　　　UIButton,UITextField,UIPageControl,继承自UIControl;

　　　　　　　　　UIControl继承自UIView;

　　UIView的动画方法:

+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion NS_AVAILABLE_IOS(4_0); // delay = 0.0, options = 0

　　补充:在按钮中添加背景图片时候设计拉伸的方法

- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets resizingMode:(UIImageResizingMode)resizingMode NS_AVAILABLE_IOS(6_0); // the interior is resized according to the resizingMode

*** 需要设置按钮的contentEdgeInsets 属性

@property(nonatomic) UIEdgeInsets contentEdgeInsets ; // default is UIEdgeInsetsZero

　　UIButton:UIButton很常用,属性虽然简单,不过初学者常会弄不清楚;

　　在设置属性的时候需要注意,UIButton中默认有

@property(nonatomic,readonly,retain) UILabel *titleLabel NS_AVAILABLE_IOS(3_0); (在UIButton不能创建titleLable属性)

@property(nonatomic,readonly,retain) UIImageView *imageView NS_AVAILABLE_IOS(3_0);

@property(nonatomic,readonly,retain) NSString *currentTitle; // normal/highlighted/selected/disabled. can return nil

@property(nonatomic,readonly,retain) UIColor *currentTitleColor; // normal/highlighted/selected/disabled. always returns non-nil. default is white(1,1)

　　在调用方法的时候容易直接用点语法,导致显示错误,正确调用方法应该是

- (void)setTitle:(NSString *)title forState:(UIControlState)state; // default is nil. title is assumed to be single line

- (void)setTitleColor:(UIColor *)color forState:(UIControlState)state

- (void)setImage:(UIImage *)image forState:(UIControlState)state; // default is nil. should be same size if different for different states

　　UITextFiled: 常用属性

@property(nonatomic,copy) NSString *text; // default is nil

@property(nonatomic,copy) NSAttributedString *attributedText NS_AVAILABLE_IOS(6_0); // default is nil

@property(nonatomic,retain) UIColor *textColor; // default is nil. use opaque black

@property(nonatomic,retain) UIFont *font; // default is nil. use system font 12 pt

@property(nonatomic) NSTextAlignment textAlignment; // default is NSLeftTextAlignment

@property(nonatomic,retain) UIView *leftView; // e.g. magnifying glass (可以在左侧预留输入空白)

@property(nonatomic) UITextFieldViewMode leftViewMode; // sets when the left view shows up. default is UITextFieldViewModeNever

　　代理方法:

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField; // return NO to disallow editing.

- (void)textFieldDidBeginEditing:(UITextField *)textField; // became first responder

- (BOOL)textFieldShouldEndEditing:(UITextField *)textField; // return YES to allow editing to stop and to resign first responder status. NO to disallow the editing session to end

- (void)textFieldDidEndEditing:(UITextField *)textField; // may be called if forced even if shouldEndEditing returns NO (e.g. view removed from window) or endEditing:YES called

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string; // return NO to not change text

- (BOOL)textFieldShouldClear:(UITextField *)textField; // called when clear button pressed. return NO to ignore (no notifications)

- (BOOL)textFieldShouldReturn:(UITextField *)textField; // called when 'return' key pressed. return NO to ignore.(在该方法中设置关闭键盘)