给控制器添加工具栏(Swift语言)

//懒加载工具条
    private lazy var toolBar: UIToolbar = UIToolbar()

//设置底部的工具条
    private func setToolBar() {
        //添加子控件
        view.addSubview(toolBar)
        
        //添加约束
        toolBar.snp_makeConstraints { (make) -> Void in
            make.bottom.left.right.equalTo(view)
            make.height.equalTo(40)
        }
        
        //通过数组设置toolBar
        var items = [UIBarButtonItem]()
        
        //添加 UIBarButtonItem
        let itemSettings = [["imageName" : "compose_toolbar_picture"],["imageName" : "compose_mentionbutton_background"],
            ["imageName" : "compose_trendbutton_background"],
            ["imageName" : "compose_emoticonbutton_background"],
            ["imageName" : "compose_add_background"]]
        //遍历itemSettings
        for dict in itemSettings {
            let btn = UIButton(type: .Custom)
            let imageName = dict["imageName"]!
            
            //设置图片
            btn.setImage(UIImage(named: imageName), forState: .Normal)
            btn.setImage(UIImage(named: imageName + "_highlighted"), forState: .Highlighted)
            
            let item = UIBarButtonItem(customView: btn)
            btn.sizeToFit()
            //把item添加到数组中
            items.append(item)
            
            //实例化弹簧
            let space = UIBarButtonItem(barButtonSystemItem: .FlexibleSpace, target: nil, action: nil)
            items.append(space)
        }
        //删除最后一个弹簧
        items.removeLast()
        
        //添加到toolBar上
        toolBar.items = items

    }

执行结果：