Question

Actually I want to draw the background of a selected NSStatusItem on the CALayer of my custom statusItemView. But since

- (void)drawStatusBarBackgroundInRect:(NSRect)rect withHighlight:(BOOL)highlight

does not work (?) on layers I ve tried it to draw the color with the backgroundColor property. But converting the selectedMenuItemColor into RGB doesn t help very much. It looks really plain without the gradient. :-/

I converted [NSColor selectedMenuItemColor] into a CGColorRef with this code:

- (CGColorRef)highlightColor {
    static CGColorRef highlight = NULL;
    if(highlight == NULL) {
        CGFloat red, green, blue, alpha;
        NSColor *hlclr = [[NSColor selectedMenuItemColor] colorUsingColorSpace:
                     [NSColorSpace genericRGBColorSpace]];
        [hlclr getRed:&red green:&green blue:&blue alpha:&alpha];
        CGFloat values[4] = {red, green, blue, alpha};
        highlight = CGColorCreate([self genericRGBSpace], values);
    }
    return highlight;
}

Any idea how to draw a native looking statusitem background on a CALayer?

Answer 1

Try subclassing CALayer and implementing the drawInContext: method to create an NSGraphicsContext for the CGContext, set the NSGraphicsContext as the current context, and then tell the status item to draw its background.

Answer 2

NSImage *backgroundImage = [[NSImage alloc] initWithSize:self.frame.size]];
[backgroundImage lockFocus];
[self.statusItem drawStatusBarBackgroundInRect:self.bounds withHighlight:YES];
[backgroundImage unlockFocus];
[self.layer setContents:backgroundImage];
[backgroundImage release];

Answer 3

I use this code in my layer delegate:

- (void)drawLayer:(CALayer *)layer 
        inContext:(CGContextRef)context {
    NSGraphicsContext* gc = [NSGraphicsContext graphicsContextWithGraphicsPort:context flipped:NO];
    [NSGraphicsContext saveGraphicsState];
    [NSGraphicsContext setCurrentContext:gc];
    [self.statusItem drawStatusBarBackgroundInRect:self.frame 
                                     withHighlight:self.isHighlighted];
    [NSGraphicsContext restoreGraphicsState];
}

友情链接