NSProgressIndicator in OS X dock icon, is showing grey, how to make standard blue
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I want to show a progress bar in my application's dock icon. It works but for some reason its showing the progress bar as a grey bar, instead of the standard blue one. I used the code I found on [another SO question][1]. What am I doing wrong?

    NSProgressIndicator *progressIndicator = [[NSProgressIndicator alloc] initWithFrame:NSMakeRect(0.0f, 0.0f, 80.0f, 20.0f)];
    [progressIndicator setStyle:NSProgressIndicatorBarStyle];
    [progressIndicator setIndeterminate:NO];
    [[[NSApplication sharedApplication] dockTile] setContentView:progressIndicator];
    [progressIndicator setDoubleValue:50];
    [[[NSApplication sharedApplication] dockTile] display];


![enter image description here][2]


  [1]: http://stackoverflow.com/questions/4004941/adding-an-nsprogressindicator-to-the-dock-icon
  [2]: http://i.stack.imgur.com/OVo74.png