How to add animated icon to OS X status bar?

Question

I want to put an icon in Mac OS status bar as part of my cocoa application. What I do right now is:

NSStatusBar *bar = [NSStatusBar systemStatusBar];

sbItem = [bar statusItemWithLength:NSVariableStatusItemLength];
[sbItem retain];

[sbItem setImage:[NSImage imageNamed:@"Taski_bar_icon.png"]];
[sbItem setHighlightMode:YES];
[sbItem setAction:@selector(stopStart)];

but if I want the icon to be animated (3-4 frames), how do I do it?

Answer 1

You'll need to repeatedly call -setImage: on your NSStatusItem, passing in a different image each time. The easiest way to do this would be with an NSTimer and an instance variable to store the current frame of the animation.

Something like this:

/*

assume these instance variables are defined:

NSInteger currentFrame;
NSTimer* animTimer;

*/

- (void)startAnimating
{
    currentFrame = 0;
    animTimer = [NSTimer scheduledTimerWithTimeInterval:1.0/30.0 target:self selector:@selector(updateImage:) userInfo:nil repeats:YES];
}

- (void)stopAnimating
{
    [animTimer invalidate];
}

- (void)updateImage:(NSTimer*)timer
{
    //get the image for the current frame
    NSImage* image = [NSImage imageNamed:[NSString stringWithFormat:@"image%d",currentFrame]];
    [statusBarItem setImage:image];
    currentFrame++;
    if (currentFrame % 4 == 0) {
        currentFrame = 0;
    }
}