UIButton上下结构垂直居中

因为项目需要,我做了一个这么一个特别的按钮

func loadSpecifitButton() {
//将图片指定大小
var image = UIImage.init(named: "img_more_update");
UIGraphicsBeginImageContext(CGSizeMake(60, 60));
image?.drawInRect(CGRectMake(0, 0, 60, 60));
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

let btnFor = UIButton.init(type: .Custom);
btnFor.setImage(image, forState: .Normal);
print(image?.size)
btnFor.setTitle("1111111111", forState: .Normal);
btnFor.setTitleColor(UIColor.blackColor(), forState: .Normal);
btnFor.frame = CGRectMake(50, 100, 100, 100);
btnFor.contentHorizontalAlignment = .Left;
btnFor.contentVerticalAlignment = .Top;
btnFor.imageEdgeInsets = UIEdgeInsetsMake(10, (btnFor.frame.size.width - (btnFor.imageView?.frame.size.width)!) / 2, 0, 0);
btnFor.titleEdgeInsets = UIEdgeInsetsMake((btnFor.imageView?.frame.size.height)! + 20, (btnFor.frame.size.width - (btnFor.titleLabel?.frame.size.width)!) / 2 - (btnFor.imageView?.frame.size.height)! - 20, 0, 0);
btnFor.layer.masksToBounds = true;
btnFor.layer.borderColor = UIColor.blackColor().CGColor;
btnFor.layer.borderWidth = 1;
self.view.addSubview(btnFor);
}

前提：UIButton: width=220, height=100, image: width=height=36 text width=62

0.想两改变两个子控件的显示位置，可以分别通过setTitleEdgeInsets和setImageEdgeInsets来实现。需要注意的是，对titleLabel和imageView设置偏移，是针对它当前的位置起作用的，并不是针对它距离button边框的距离的。把button的contentHorizontalAlignment设为居左时，contentVerticalAlignment设为居上时，可以很方便的通过EdgeInsets改变两个子控件的位置。

1.先让image向下偏移10(距离上边间隙)，然后向右偏移92( button.width - image.width / 2)，计算下来为 [btn setImageEdgeInsets:UIEdgeInsetsMake(5, 92, 0, 0)]，它的偏移是针对它图1时的位置，如果想向上偏移传的为负值。

2.计算机文本偏移了，向下偏移46 (36+10 图片的高度+间隙)，向右偏移44 ( (button.width - text.width) / 2 - image.width );因为文本本身起始x方向位置是从image.width开始的，所以算偏移时，要减掉这个宽度。计算结果为[btn setTitleEdgeInsets:UIEdgeInsetsMake(46, 44, 0, 0)];