设置控件内容的上下对齐方法

control.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter

typedefenum {

UIControlContentVerticalAlignmentCenter  = 0,

UIControlContentVerticalAlignmentTop     = 1,

UIControlContentVerticalAlignmentBottom  = 2,

UIControlContentVerticalAlignmentFill    = 3,

} UIControlContentVerticalAlignment;

typedefenum {

UIControlContentHorizontalAlignmentCenter = 0,

UIControlContentHorizontalAlignmentLeft   = 1,

UIControlContentHorizontalAlignmentRight  = 2,

UIControlContentHorizontalAlignmentFill   = 3,

} UIControlContentHorizontalAlignment;

@property(nonatomic) UIControlContentVerticalAlignment contentVerticalAlignment;     // how to position content vertically inside control. default is center

@property(nonatomic) UIControlContentHorizontalAlignment contentHorizontalAlignment; // how to position content hozontally inside control. default is centerｑｑ