Customize your scrollers

[michael]

Apple did - so must you!
No, but seriously, only if you have an actual need for different scrollers. It's actually quite easy. Just a couple easy steps.

1) Create a new subclass of NSScroller.
2) Set the scroller of the view to be a new instance of this scroller
3) Decide which parts you want to draw different
* I'll show just the knob, but the rest are easy as well
4) Reimplement the following:
- (void)drawKnob;
...that's it!
5) Draw the knob ... here's just a solid color:

- (void)drawKnob {
[[NSColor redColor] set]; //set knob color to red
NSRect knobRect = [self rectForPart:NSScrollerKnob];
NSRectFill(knobRect);
}

You now have a red, rectangular scroller!!! Using this method, you can customize every part of the scroller, including the arrows and highlighting. Go nuts!

Michael

p.s. Please read the documentation before doing this. If you want to draw anything other than the arrows or the knob, you'll need to draw all of the rest using - (void)drawParts.

[dbachrach]

That is awesome. Really simple hack.

I might throw that into one of my programs as an experiment.

[michael]

Maybe I could do a once a week coding trick. I wonder if there'd be an interest in that...

[nicks]

Yeah Michael - that'd be pretty cool - in fact, work it up as a weekly TAB post. Then you could reference the post here, and address questions.... just a thought.

[michael]

True. I could even take suggestions here on the boards as well.

[axel]

seems like a good idea

[sprint]

Neat!

[baseballboy828]

Cool idea!

[Disparity]

Has anyone noticed how a scroller will flicker when the view it contains (assuming the scroller to be part of a scrollview) no longer fits in the window (i.e. on a window resize)?

[llamame]

Thanks for the weekly coding tips.