Swift自定义Tool

    //设置tool
    private func prepareToolBar(){
        
        let toolBar = UIToolbar()
        view.addSubview(toolBar)
        let w = UIScreen.mainScreen().bounds.size.width
        toolBar.ff_AlignInner(type: ff_AlignType.BottomLeft, referView: view, size: CGSize(width: w, height: 44))
        
        let items  = [["imageName": "compose_toolbar_picture"],["imageName": "compose_mentionbutton_background"],["imageName": "compose_trendbutton_background"],["imageName": "compose_emoticonbutton_background"],["imageName": "compose_addbutton_background"]]
        
        //初始化一个按钮的数组
        var btnItems = [UIBarButtonItem]()
        for dict in items{
            btnItems.append(UIBarButtonItem(customView: UIButton(imageName: dict["imageName"]!)))
            btnItems.append(UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.FlexibleSpace, target: nil, action: nil))
        }
        //移除最后一个拉伸弹簧
        btnItems.removeLast()
        
        toolBar.items = btnItems
        
    }

//配合分类
extension UIButton{
    
    /// 便利构造函数
    ///
    /// - parameter imageName: 图像名称
    ///
    /// - returns: UIButton
    convenience init(imageName: String){
        self.init()
        
        setImage(UIImage(named: imageName), forState: UIControlState.Normal)
        setImage(UIImage(named: imageName + "_highlighted"), forState: UIControlState.Highlighted)
        sizeToFit()
    }

}