Clear NSView programmatically in swift

问题

I have a NSView connected to a custom class.
There's some drawing on that view:

class LineDrawer: NSView {
    var linear = NSBezierPath()
    var storage = NSUserDefaults.standardUserDefaults()

    override func drawRect(dirtyRect: NSRect) {
        var color = NSColor()

        if let newLoadedData = storage.objectForKey("color") as? NSData {
            if let currentColor = NSUnarchiver.unarchiveObjectWithData(newLoadedData) as? NSColor {
                color = currentColor
            }
        }

        color.set()
        linear.lineWidth = CGFloat(storage.integerForKey("width"))
        linear.stroke()
    }

    override func mouseDown(theEvent: NSEvent) {
        super.mouseDown(theEvent)
        let location = theEvent.locationInWindow
        var lastPt = theEvent.locationInWindow
        lastPt.y -= frame.origin.y
        linear.moveToPoint(lastPt)
    }

    override func mouseDragged(theEvent: NSEvent) {
        super.mouseDragged(theEvent)
        var newPt = theEvent.locationInWindow
        newPt.y -= frame.origin.y
        linear.lineToPoint(newPt)
        needsDisplay = true
    }
}

And now I need to write a function to completely clear that view.

回答1:

Not too sure what you mean by completely clear that view but can't you just fill it with a solid colour?

[[NSColor windowBackgroundColor] setFill];
NSRectFill(self.bounds);

(Not up to speed with the Swift hotness yet)

update I improving my Swift chops behold!

NSColor.windowBackgroundColor().setFill()
NSRectFill(self.bounds)

回答2:

Something like this should suffice. I used something like this in my project to clear NSView.

while curView.subviews.count > 0 {
   curView.subviews.last?.removeFromSuperview()
}

回答3:

Swift 4.2 solution:

myView.subviews.removeAll()

来源：https://stackoverflow.com/questions/28248467/clear-nsview-programmatically-in-swift