xib 设置圆角小技巧

作者: AlwaysBlue | 来源:发表于2016-01-13 18:00 被阅读2890次

在xib中，可以根据用户定义运行时属性，设置key path来修改。但是有一个很麻烦的事情，每个对象都要分别设置key path，选择类型，设置value。

那么下面介绍一下如何将你想要设置的下图中的内容

xib或者storyboard中原来的样子

如何变成下图中的内容

通过写代码变成这个样子，是不是就很简单了

通过自定义的image view 我们就可以直接输入值即可.

在代码中，关键的内容便是IB_DESIGNABLE IBInspectable（在Swift中是@IBInspectable @IBDesignable）。下面是在苹果文档中对两个关键字的解释

When you add the IB_DESIGNABLEattribute to the class declaration, class extension, or category for a custom view, Interface Builder renders your custom view on the canvas. When you make changes to your code, Interface Builder rebuilds your custom view and rerenders your custom view.

（当你在类的声明，类扩展，类别，IB会将你的自定义视图直接在画布上显示出来。）

By using the IBInspectable attribute to declare variables as inspectable properties, you allow Interface Builder to quickly rerender your custom view as you change the values of these properties in the Attributes inspector. You can attach the IBInspectable attribute to any property in a class declaration, class extension, or category for any type that’s supported by the Interface Builder defined runtime attributes: boolean, integer or floating point number, string, localized string, rectangle, point, size, color, range, and nil.

当你使用IBInspectable属性去声明变量，可以让IB很快地将你做出的属性改变显示在自定义view上。IBInspectable只能添加到Interface Builder defined runtime attributes支持的boolean, integer or floating point number, string, localized string, rectangle, point, size, color, range, and nil类型中。