UIButton状态:添加图片：

UIButton状态:
UIControlStateNormal          // 正常状态  
UIControlStateHighlighted     // 高亮状态  
UIControlStateDisabled        // 禁用状态   
UIControlStateSelected        // 选中状态   
UIControlStateApplication     //    
UIControlStateReserved        // 保留状态
UIButton类型:
UIButtonTypeCustom            //自定义类

添加图片：
灰色背景颜色：
UIButtonTypeRoundedRect       //圆角类型
 UIButtonTypeDetailDisclosure   //细节展示按钮

UIButtonTypeInfoLight          //浅色背景的信息按钮

UIButtonTypeInfoDark           //暗色背景的信息按钮

UIButtonTypeContactAdd         // 添加按钮

创建UIButton 1. UIButton *button = [[UIButton alloc] initWithFrame: CGRectMake (x, y, Width, Height)];      2. UIButton *button = [[UIButton buttonWithType:UIButtonTypeCustom] retain];    设置UIButton标题 [button setTitle:title forState:UIControlStateNormal];      设置UIButton标题颜色 [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];   设置UIButton背景图片 [button setBackgroundImage:newImage forState:UIControlStateNormal];   设置UIButton背景颜色 button.backgroundColor = [UIColor clearColor];

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