对于UIbutton的两个属性imageInset、titleInset一直没有太明白，最近研究了一下，对于不对的地方，欢迎指正啊。

首先要理解，这里的（top、left、bottom、right）并不是直接代表距离button的边界距离，而是现在的一个边界距离相对以前的偏移量，系统默认条件下，图片在左，文字在右。

接着就需要计算出原始image的宽高，title的原始位置，以及现在的位置，下面是简单实现的代码：

-(void)test1//图片在左，文字在右

{

self.button1.contentHorizontalAlignment=UIControlContentHorizontalAlignmentRight;

//self.button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;

//以上这两个设置都是可以的

CGFloattitleWidth =60;

CGFloatshowImageWidth =30;

CGFloatoriginalImageWidth =self.button1.frame.size.width>ImageWidth?ImageWidth:self.button1.frame.size.width;

CGFloatleftInset = (self.button1.frame.size.width-titleWidth-showImageWidth)/2;

CGFloatrightInset = leftInset;

CGFloattitleOrigionX = originalImageWidth;

[self.button1setImageEdgeInsets:UIEdgeInsetsMake(0, leftInset,0, rightInset+titleWidth)];

[self.button1setTitleEdgeInsets:UIEdgeInsetsMake(0, leftInset+showImageWidth-titleOrigionX,0, rightInset)];

}

实现效果：

-(void)test2//文字在左，图片在右

{

//self.button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;

self.button1.contentHorizontalAlignment=UIControlContentHorizontalAlignmentLeft;

//以上这两种设置都可以

CGFloattitleWidth =60;

CGFloatshowImageWidth =30;

CGFloatoriginalImageWidth =self.button1.frame.size.width>ImageWidth?ImageWidth:self.button1.frame.size.width;

CGFloatleftInset = (self.button1.frame.size.width-titleWidth-showImageWidth)/2;

CGFloatrightInset = leftInset;

CGFloattitleOrigionX = originalImageWidth;

[self.button1setImageEdgeInsets:UIEdgeInsetsMake(0, leftInset+titleWidth,0, rightInset)];

[self.button1setTitleEdgeInsets:UIEdgeInsetsMake(0, leftInset-titleOrigionX,0, rightInset+showImageWidth)];

}

实现效果：

-(void)test3//图片在上，文字在下

{

//self.button2.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;

self.button2.contentHorizontalAlignment=UIControlContentHorizontalAlignmentLeft;

//以上这两个设置都是可以的

CGFloattitleWidth =60;

CGFloattitleHight =20;

CGFloatshowImageWidth =30;

CGFloatshowImageHight = showImageWidth;

CGFloatoriginalImageWidth =self.button2.frame.size.width>ImageWidth?ImageWidth:self.button2.frame.size.width;

CGFloattitleOrigionX = originalImageWidth;

CGFloatimageLeftInset = (self.button2.frame.size.width-showImageWidth)/2;

CGFloatimageRightInset = imageLeftInset;

CGFloattitleLeftInset = (self.button2.frame.size.width-titleWidth)/2;

CGFloattitleRightInset = titleLeftInset;

CGFloattopInset = (self.button2.frame.size.height-showImageHight-titleHight)/2;

CGFloatbottomInset = topInset;

[self.button2setImageEdgeInsets:UIEdgeInsetsMake(topInset,imageLeftInset, titleHight+bottomInset,imageRightInset)];

[self.button2setTitleEdgeInsets:UIEdgeInsetsMake(topInset+showImageHight, titleLeftInset-titleOrigionX, bottomInset, titleRightInset)];

}

实现效果：