Swift

1，图片左中右三宫格缩放形式 //左右14像素不变形，中间缩放 let imgTrackRight = UIImage(named:"slider_max") let imgRight = imgTrackRight!.stretchableImageWithLeftCapWidth(14, topCapHeight:0) slider.setMaximumTrackImage(imgRight, forState:UIControlState.Normal) 2，图片上中下三宫格缩放形式 //上下10像素不变形，中间缩放 let imgBgSouce = UIImage(named:"bg") let imgBg = imgBgSouce!.stretchableImageWithLeftCapWidth(0, topCapHeight:10) 3，图片9宫格缩放 //左右14像素,上下10像素不变形，中间缩放 let imgBgSouce = UIImage(named:"bg") let imgBg = imgBgSouce!.stretchableImageWithLeftCapWidth(14, topCapHeight:10)