Swift 实现UIButton图片与文字布局调整

最近再次学习Swift，所以会翻译一些之前OC常用的一些组件

今天要介绍的是Swift中实现UIButton内部图片与文字的布局调整，下面是效果图，先简单的看一下

左右布局

上下布局

这种方式我们可以通过自定义按钮去实现，也可以通过分类去实现，既然能通过分类解决的问题，就没有必要去自定义一个新的按钮了，笔者在开发过程中还是比较喜欢使用分类去解决一些问题的

我们先来来看下一如何去调用

        leftBtn.sg_setImage(location: .left, space: 10) { (btn) in
            btn.setTitle("left btn", for: .normal)
            btn.setImage(UIImage.init(named: "test_img"), for: .normal)
        }

一句代码搞定是不是很爽，这是带有block的方法，推荐使用，在block内部进行设置按钮的文字及颜色，由于是调整图片与文字布局，那就必须先设置文字与图片才能调整，所以推荐使用带有block的方法去掉用，笔者工作中也是一直使用这种方式

再来看一下内部实现代码

    ///
    /// Set image location
    ///
    /// Image and title must be set before this method will work
    ///
    /// - parameter location: Location of image relative to title
    /// - parameter space: Space between image and title
    ///
    func sg_setImage(location: SGImageLocation, space: CGFloat) {
        
        let imageView_Width = self.imageView?.frame.size.width
        let imageView_Height = self.imageView?.frame.size.height
        let titleLabel_iCSWidth = self.titleLabel?.intrinsicContentSize.width
        let titleLabel_iCSHeight = self.titleLabel?.intrinsicContentSize.height
        
        switch location {
        case .left:
            if self.contentHorizontalAlignment == .left {
                self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: space, bottom: 0, right: 0)
            } else if self.contentHorizontalAlignment == .right {
                self.imageEdgeInsets = UIEdgeInsets.init(top: 0, left: 0, bottom: 0, right: space)
            } else {
                let spacing_half = 0.5 * space;
                self.imageEdgeInsets = UIEdgeInsets.init(top: 0, left: -spacing_half, bottom: 0, right: spacing_half)
                self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: spacing_half, bottom: 0, right: -spacing_half)
            }
        case .right:
            let titleLabelWidth = self.titleLabel?.frame.size.width
            if self.contentHorizontalAlignment == .left {
                self.imageEdgeInsets = UIEdgeInsets.init(top: 0, left: titleLabelWidth! + space, bottom: 0, right: 0)
                self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: -imageView_Width!, bottom: 0, right: 0)
            } else if self.contentHorizontalAlignment == .right {
                self.imageEdgeInsets = UIEdgeInsets.init(top: 0, left: 0, bottom: 0, right: -titleLabelWidth!)
                self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: 0, bottom: 0, right: imageView_Width! + space)
            } else {
                let imageOffset = titleLabelWidth! + 0.5 * space
                let titleOffset = imageView_Width! + 0.5 * space
                self.imageEdgeInsets = UIEdgeInsets.init(top: 0, left: imageOffset, bottom: 0, right: -imageOffset)
                self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: -titleOffset, bottom: 0, right: titleOffset)
            }
        case .top:
            self.imageEdgeInsets = UIEdgeInsets.init(top: -(titleLabel_iCSHeight! + space), left: 0, bottom: 0, right: -titleLabel_iCSWidth!)
            self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: -imageView_Width!, bottom: -(imageView_Height! + space), right: 0)
        case .bottom:
            self.imageEdgeInsets = UIEdgeInsets.init(top: titleLabel_iCSHeight! + space, left: 0, bottom: 0, right: -titleLabel_iCSWidth!)
            self.titleEdgeInsets = UIEdgeInsets.init(top: 0, left: -imageView_Width!, bottom: imageView_Height! + space, right: 0)
        }
    }

最后附上代码下载地址 内部有一些平时工程中需要的一些分类