Journal of a Maker

So, you’re writing an awesome multimedia application for the iPhone. Everything’s going swimmingly, and you even have some nice animation effects for when the iPhone is plugged into an external accessory, just like the iPod app:

- (void)toggleVolumeDisplay: (BOOL)show
{
	BOOL isShowing = (volumeSlider.alpha > 0.0);
	if( isShowing && !show )
	{
		// Animate volume slider down and out, while animating play controls to center of view
	}
	else if( !isShowing && show )
	{
		// Animate volume slider in, while animating play controls up to the top of the view
	}
}

Or something like that. That’s purely to illustrate what you might be doing in response to a run-of-the-mill hardware route change (headphones plugged in, connected to speaker dock, etc.), which of course you’re detecting like this:

	// When the view is loaded
	AudioSessionAddPropertyListener( kAudioSessionProperty_AudioRouteChange, RouteChangeListener, (void *)self);

	// Called later as part of your listener callback
	CFStringRef state = nil;
	UInt32 propertySize = sizeof(CFStringRef);
	OSStatus result = AudioSessionGetProperty( kAudioSessionProperty_AudioRoute, &propertySize, &state);
	if( result == kAudioSessionNoError)
	{
		if( CFStringGetLength(state) > 0)
		{
			if ([(NSString *)state compare:@"LineOut"] == NSOrderedSame) // only special case we care about
				shouldShowVolumeControl = NO;
		}
		else
			; // vibrate switch engaged
	}
	else
	{
		if (result == kAudioSessionUnsupportedPropertyError)
			shouldShowVolumeControl = NO; // probably simulator
		else
			; // error encountered
	}

This has been documented in plenty of places.
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For the past year, I’ve been employed by 352 Media Group, based first in Gainesville, FL and then in Atlanta GA.

Recently, I decided that the time had come for me to try to make it as a freelancer. I’m not the kind of person who thinks everyone should follow the path of self-employment. On the other hand, there comes a point in some of our lives where the idea of working for someone else is so distasteful that the inevitable pain and isolation that comes from going it alone is actually attractive. Continue reading »

Okay, so you’re spelunking around in Mac OS using Terminal. You try to ‘cd’ into a directory only to be told that what you’re trying to get to “is not a directory.” Then you remember that the target directory is actually a shortcut that you created with Finder. It looks just link a symlink in Finder, so shouldn’t it act like one in Terminal?

Unfortunately, in OS X, aliases are treated differently by the command line than symlinks. In particular, they won’t be followed by the “cd” command, leading to your present frustration. Fortunately, with a little elbow grease, you can patch up your shell and be on your merry way. Continue reading »