xcode – 尝试实例化笔尖时IBDesignable崩溃

@IBDesignable
class ABCMyView: UIView {
    // (IBOutlets and other code omitted)

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        commonInit()
    }

    override init(frame: CGRect) {
        super.init(frame: frame)
        commonInit()
    }

    private func commonInit() {
        let nib = UINib(nibName: "ABCMyViewContents",bundle: NSBundle.mainBundle())
        let view = nib.instantiateWithOwner(self,options: nil).first as! UIView
        addSubview(view)
    }
}

尝试在Interface Builder中查看ABCMyView时,它崩溃了.尝试调试崩溃会导致它在尝试使用所有者实例化nib的行上崩溃.没有错误消息,只是堆栈跟踪最终在汇编代码中(libobjc.A.dylib`objc_exception_throw :).

这是我在异常断点上在控制台中尝试过的一些事情：

(lldb) po nib
<UINib: 0x78ef8f20>


(lldb) po nib.instantiateWithOwner(self,options: nil)
error: Execution was interrupted,reason: breakpoint 1.1.
The process has been returned to the state before expression evaluation.

当我运行应用程序时,一切都运行正常,只有在尝试查看Interface Builder中的UIView失败时才会这样.

如何从IBDesignable加载Nib文件？