There are a couple of tips on the site for dealing with fade-in/out effects for windows, but the trick seems to be a bit more difficult for NSView’s. FadeAViewAndItsContents has one option, but it requires creating a helper NSWindow object to hold the NSView in question. In my particular app, I want to fade a view in and out of visibility when the app is in full screen mode (think: QuickTime’s controller when you’re watching a movie full screen). Using a helper NSWindow wasn’t an option since only one window can appear at the CGShieldingWindowLevel(). The helper wouldn’t be visible.

So I came up with a little category on NSView that does the trick nicely, albeit in Tiger only. The code fails gracefully in my build environment since I build separate Panther and Tiger versions for other reasons. It should be possible to add runtime checks to make the code work in a unified build for both OS’s, but I haven’t added it at this point. Any additions would of course be welcome.

NSView+Fade.h:

#import <Cocoa/Cocoa.h>

@interface NSView(Fade)

• (IBAction)setHidden:(BOOL)hidden withFade:(BOOL)fade; @end

NSView+Fade.m:

#import “NSView+Fade.h”

/** A category on NSView that allows fade in/out on setHidden: */ @implementation NSView(Fade) /** Hides or unhides an NSView, making it fade in or our of existance. @param hidden YES to hide, NO to show @param fade if NO, just setHidden normally. */

• (IBAction)setHidden:(BOOL)hidden withFade:(BOOL)fade { if(!fade) { // The easy way out. Nothing to do here… [self setHidden:hidden]; } else { // FIXME: It would be better to check for the availability of NSViewAnimation at runtime intead // of at compile time. I’m lazy, and I make two builds anyways, so I do it at compile. -ZSB #if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_4 // We’re building for (at least) Tiger, so we can use NSViewAnimation if(!hidden) { // If we’re unhiding, make sure we queue an unhide before the animation [self setHidden:NO]; } NSMutableDictionary *animDict = [NSMutableDictionary dictionaryWithCapacity:2]; [animDict setObject:self forKey:NSViewAnimationTargetKey]; [animDict setObject:(hidden ? NSViewAnimationFadeOutEffect : NSViewAnimationFadeInEffect) forKey:NSViewAnimationEffectKey]; NSViewAnimation *anim = [[NSViewAnimation alloc] initWithViewAnimations:[NSArray arrayWithObject:animDict]]; [anim setDuration:0.5]; [anim startAnimation]; [anim autorelease]; #else // We’re building for Panther, so just do a normal hide [self setHidden:hidden]; #endif }

} @end

The above code is placed in the public domain if anyone cares to use it.

• ZacBedell

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See also AMViewAnimation. –!Andy :) —-