UIButton

UIButton即按钮，可以通过两种方法定义：

1）initWithFrame

	UIButton *btn=[[UIButton alloc]initWithFrame:CGRectMake(60, 60, 200, 60)];
   	btn.backgroundColor=[UIColor greenColor];
    	[btn setTitle:@"xuan" forState:UIControlStateNormal];
    	[self.view addSubview:btn];

   2)buttonWithType

	
	UIButton *btn2=[UIButton buttonWithType:UIButtonTypeRoundedRect];
    	CGRect rect=CGRectMake(60, 160, 200, 60);
    	btn2.frame=rect;
    	btn2.tag=1001;
    	btn2.backgroundColor=[UIColor colorWithRed:30/255.0 green:200/255.0 blue:125/255.0 alpha:1.0];
    	[btn2 setTitle:@"xuan" forState:UIControlStateNormal];
    	[btn2 addTarget:self action:@selector(btn2Pressed) forControlEvents:UIControlEventTouchDown];
    	[self.view addSubview:btn2];

	-(void)btn2pressed{
	NSLog(@"Button pressed!");

	}

	button的type类型：

	
typedef enum {
    UIButtonTypeCustom = 0,           // no button type   自定义，无风格
    UIButtonTypeRoundedRect,          // rounded rect, flat white button, like in address card 白色圆角矩形，类似偏好设置表格单元或者地址簿卡片
    UIButtonTypeDetailDisclosure,//蓝色的披露按钮，可放在任何文字旁
    UIButtonTypeInfoLight,//微件(widget)使用的小圆圈信息按钮，可以放在任何文字旁
    UIButtonTypeInfoDark,//白色背景下使用的深色圆圈信息按钮
    UIButtonTypeContactAdd,//蓝色加号(+)按钮，可以放在任何文字旁
} UIButtonType;

    UIButton常用的设置方法：

	
	   //设置对应状态的标题内容default is nil. title is assumed to be single line
	- (void)setTitle:(NSString *)title forState:(UIControlState)state;  
	//设置对应状态的标题颜色           
	- (void)setTitleColor:(UIColor *)color forState:(UIControlState)state;   
	//设置对应状态的标题阴影颜色            
	- (void)setTitleShadowColor:(UIColor *)color forState:(UIControlState)state;          
	//设置对应状态的按钮的图片
	- (void)setImage:(UIImage *)image forState:(UIControlState)state;        
	//设置对应状态的按钮背景图片
	- (void)setBackgroundImage:(UIImage *)image forState:(UIControlState)state; 
	UIButton的常用属性：
	titleLabel,buttonType,currentTitle,currentTitleColor,currentTitleShadowColor,currentImage,currentBackgroundImage,imageView,