UIButton

    checkBox.contentEdgeInsets = UIEdgeInsetsMake(10, 10, 10, 10);//设置内容的内边距
    checkBox.imageEdgeInsets = UIEdgeInsetsMake(10, 10, 10, 10);//设置图片的外边距
    checkBox.titleEdgeInsets = UIEdgeInsetsMake(10, 10, 10, 10);//标题的外边距