UIImageView subclass method for setting up and animating an image sequence

gistfile1.m

- (void)setFramesWithFirstFrame:(NSString *)fileName;
{
   //  DLog(@"firstFrame: %@",fileName);
  [self setImage:[UIImage imageNamed:fileName]];
	
	// split the `fileName` into a base and number. then incrememnt the number until imageNamed returns nil.
	
	// check for numbers in the filename
	NSRange pngRange = [fileName rangeOfString:@".png"];
	NSRange numberRange;
	
	// if we don't find any numbers, bail out.
	if ( pngRange.location == NSNotFound ) {
		DLog(@"No number found. Not setting frames.");
		return;
	} else {
		numberRange = NSMakeRange(pngRange.location-2, 2);
	}
	
	// grab the numbers we found
	NSString *tmpNumberString = [fileName substringWithRange:numberRange];
	NSNumberFormatter *tmpNumberFormatter = [[NSNumberFormatter alloc] init];
	[tmpNumberFormatter setNumberStyle:NSNumberFormatterDecimalStyle];
	NSNumber *tmpNumber = [tmpNumberFormatter numberFromString:tmpNumberString];
	
	// check the result
	if ( tmpNumber == nil ) {
		DLog(@"Number conversion failed. Not setting frames.");
		return;
	}
	
	// now we have:
	//  - fileName - @"foo00.png"
	//  - tmpNumber - number of first frame
	//  - tmpNumberFormatter - we can re-use this to format our frame numbers
	
	// format the number formatter
	[tmpNumberFormatter setMinimumIntegerDigits:2];
	[tmpNumberFormatter setMaximumIntegerDigits:2];
	
	// get the base filename to iterate on
	NSString *tmpBaseFilename = [fileName substringToIndex:numberRange.location];
	
	// a place to put the frames
	NSMutableArray *tmpFrames = [NSMutableArray array];
	
	// keep track of if we should keep looking
	BOOL keepLooking = YES;
	
	// start looking for frames!
	while ( keepLooking ) {
		
		// prepare a frame string
		NSString *tmpFrameString = [tmpNumberFormatter stringFromNumber:tmpNumber];
		
		// incrememnt the number
		tmpNumber = [NSNumber numberWithInt:[tmpNumber integerValue]+1];
		
		// what filename are we looking for?
		NSString *tmpFilenameString = [tmpBaseFilename stringByAppendingString:tmpFrameString];
		
		// look for a frame!
		UIImage *tmpImage = [UIImage imageNamed:tmpFilenameString];
		
		if ( tmpImage ) {
			[tmpFrames addObject:tmpImage];
		} else {
			// DLog(@"image not found (%@), bailing out.",tmpFilenameString);
			keepLooking = NO;
		}
	}
	
	// check for any frames
	if ( tmpFrames.count > 0 ) {
		[self setAnimationImages:tmpFrames];
		[self startAnimating];
	} else {
		DLog(@"no frames found after processing, none set.");
	}
}