How to pin layer in window (view)

Question

Imagine a yellow box (CALayer instance) drawn in the its parent layer (which is the root layer of a layer-backing NSView).

When the frame of the parent view changes, the yellow box should remain at the same position on the screen. When i set up autoresizing masks to NSViewMinXMarging and NSViewMaxXMarging the yellow box move on the screen proportionally between changing view width...

How can I adjust the frame of the NSWindow (NSView) while keeping the child layer at its initial position?

I know about - (void)layoutSublayersOfLayer:(CALayer *)layer CALayerDelegate method but i did not have an idea how to implement this behavior.

Here is demo:

Answer 1

This is my approach. Subclass NSWindow.

.h-file:

#import <Cocoa/Cocoa.h>
#import <QuartzCore/QuartzCore.h>

@interface NNMainWindow : NSWindow <NSWindowDelegate> {

    CALayer* yellowLayer;

    NSRect leftEdge;
    NSRect rightEdge;
    NSRect topEdge;
    NSRect bottomEdge;
}
@end

.m-file:

#import "NNMainWindow.h"

@implementation NNMainWindow

- (void)awakeFromNib {

    //Add yellow layer here....

    [self setAcceptsMouseMovedEvents:YES];

    [self updateResizingMarkers];
}

- (void)updateResizingMarkers {
    NSSize horizontalRectSize = NSMakeSize(NSWidth(self.frame), 8.f);
    horizontalRectSize.width += 10.f;
    NSSize verticalRectSize = NSMakeSize(8.f, NSHeight(self.frame));
    verticalRectSize.height += 10.f;

    leftEdge = NSZeroRect;
    leftEdge.size = verticalRectSize;
    leftEdge.origin = NSMakePoint(-5.f, -5.f);

    rightEdge = NSZeroRect;
    rightEdge.size = verticalRectSize;
    rightEdge.origin = NSMakePoint(horizontalRectSize.width - 10.f - 3.f, -5.f);
}

- (void)mouseMoved:(NSEvent *)theEvent {

    NSPoint currentLocation = [theEvent locationInWindow];

    if (NSPointInRect(currentLocation, leftEdge))
        yellowLayer.autoresizingMask = kCALayerMinXMargin;

    if (NSPointInRect(currentLocation, rightEdge))
        yellowLayer.autoresizingMask = kCALayerMaxXMargin;
}

- (void)windowDidResize:(NSNotification *)notification {
    [self updateResizingMarkers];
}

@end