How to change color of divider in NSSplitView?

Question

Can we change the color of the divider? Apple documentations says, that we can override -dividerColor in subclass of NSSplitView for this, but it doesn't works for me, or my understanding isn't correct. Also I've try create color layer over divider, e.g.:

colorLayer = [CALayer layer];
NSRect dividerFrame = NSMakeRect([[self.subviews objectAtIndex:0] frame].size.width, [[self.subviews objectAtIndex:0] frame].origin.y, [self dividerThickness], self.frame.size.height);

[colorLayer setBackgroundColor:[color coreGraphicsColorWithAlfa:1]];
[colorLayer setFrame:NSRectToCGRect(dividerFrame)];

[self.layer addSublayer:colorLayer];

Not works.

Answer 1

This answer may be late but:
If you are using Interface Builder, it is possible to change the property by going to the Identity Inspector of the NSSplitView (cmd+alt+3) and adding a User Defined Runtime Attribute for dividerColor of the type Color.

Answer 2

Actually, simply subclassing NSSplitView and overriding -(void)dividerColor works, but works only for thin or thick divider.

I've created simple configurable split view like this:

@interface CustomSplitView : NSSplitView
@property NSColor* DividerColor
@end

@implementation CustomSplitView
- (NSColor*)dividerColor {
  return (self.DividerColor == nil) ? [super dividerColor] : self.DividerColor;
}
@end

Then in Interface Builder specify custom class for your split view to be CustomSplitView and add new user defined runtime attribute with key path = DividerColor, type = Color and select desired splitter color.

Answer 3

I've tried subclassing - (void)dividerColor too and I'm not sure why it doesn't work even though I know it's being called (and it's in the documentation).

One way to change the color of the divider is to subclass - (void)drawDividerInRect:(NSRect)aRect. However, for some reason, this method isn't called and I've checked all over the web for answers, but couldn't find anything, so I ended up calling it from drawRect. Here is the code for the subclassed NSSplitView:

-(void) drawRect {
    id topView = [[self subviews] objectAtIndex:0];
    NSRect topViewFrameRect = [topView frame];
    [self drawDividerInRect:NSMakeRect(topViewFrameRect.origin.x, topViewFrameRect.size.height, topViewFrameRect.size.width, [self dividerThickness] )];
}

-(void) drawDividerInRect:(NSRect)aRect {
    [[NSColor redColor] set];
    NSRectFill(aRect);
}