如何填充nsScrollView的右下角?

已经 answered elsewhere on stackoverflow 梅肯托斯。子类的类是nsscrollview。

@interface MyScrollView : NSScrollView {
}
@end


@implementation MyScrollView

- (void)drawRect:(NSRect)rect{
    [super drawRect: rect];

    if([self hasVerticalScroller] && [self hasHorizontalScroller]){
        NSRect vframe = [[self verticalScroller]frame];
        NSRect hframe = [[self horizontalScroller]frame];
        NSRect corner;
        corner.origin.x = NSMaxX(hframe);
        corner.origin.y = NSMinY(hframe);
        corner.size.width = NSWidth(vframe);
        corner.size.height = NSHeight(hframe);

        // your custom drawing in the corner rect here
        [[NSColor redColor] set];
        NSRectFill(corner);
    }
}
@end

有点奇怪,但只是子类化nsscrollview和用super.drawrect()覆盖draw,使我的nsscrollview(不是)用白色填充那个角。我测试了2倍以确定,因为这没什么意义。

import Cocoa

class ThemedScrollView: NSScrollView {
    override func drawRect(dirtyRect: NSRect) {
        super.drawRect(dirtyRect)
    }
}

以下是原始答案的快速变化:

import Cocoa

class ThemedScrollView: NSScrollView {

    override func drawRect(dirtyRect: NSRect) {
        super.drawRect(dirtyRect)

        if hasVerticalScroller && hasHorizontalScroller {
            guard verticalScroller != nil && horizontalScroller != nil else { return }

            let vFrame = verticalScroller!.frame
            let hFrame = horizontalScroller!.frame
            let square = NSRect(origin: CGPoint(x: hFrame.maxX, y: vFrame.maxY), size: CGSize(width: vFrame.width, height: hFrame.height))

            let path = NSBezierPath(rect: square)
            let fillColor = NSColor.redColor()
            fillColor.set()
            path.fill()
        }
    }
}