当mainWindow改变时重画NSView

Question

我想根据焦点是否改变NSView的背景。

我发现这个问题：Change NSView background color when window has focus

而且除了当窗口失去或获得集中重绘不会触发第一个答案工作正常。

如何在mainWindow更改时触发重绘？

Answer 1

在你NSWindow委托：

func windowDidBecomeMain(notification: NSNotification) { 
    let theView = ... 
    theView.needsDisplay = true 
} 

func windowDidResignMain(notification: NSNotification) { 
    let theView = ... 
    theView.needsDisplay = true 
} 

在你NSView子类：

func drawRect(rect: NSRect) { 
    if self.window.isMainWindow { 
     // draw active appearance 
    } else { 
     // draw inactive appearance 
    } 
}