//设置图片居右

-(void)setImageToRight

{

NSDictionary *attribute = @{NSFontAttributeName:btn.titleLabel.font};

//获取文本的宽度

CGFloat btnWidth = [btn.titleLabel.text boundingRectWithSize:CGSizeMake(0, 24)

options:\

NSStringDrawingTruncatesLastVisibleLine |

NSStringDrawingUsesLineFragmentOrigin |

NSStringDrawingUsesFontLeading

attributes:attribute

context:nil].size.width;

//通过调节文本和图片的内边距到达目的

btn.imageEdgeInsets = UIEdgeInsetsMake(0, btnWidth, 0, -btnWidth);

[btn setTitleEdgeInsets:UIEdgeInsetsMake(0, -btn.imageView.image.size.width, 0, btn.imageView.image.size.width)];

}