Loading UITableView Images/Assets

	//Taken from and used with:
	// http://stackoverflow.com/questions/16663618/async-image-loading-from-url-inside-a-uitableview-cell-image-changes-to-wrong
	////////////////////
	//With SDWebImage //
	////////////////////
	(don't use the below method. This one is king.)
	//Import the goods and use PODS
	// pod 'SDWebImage', '~> 3.7'
	//
	#import <SDWebImage/UIImageView+WebCache.h>
	- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
	{
	//Custom tableViewCell
	static NSString *CellIdentifier = @"VideoCell";
	VideoCell *cell = (VideoCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
	if (cell == nil)
	{
	cell = [[VideoCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
	}
	VideoObject *video = [VideoObject new];
	video = [self.safetyVideos objectAtIndex:indexPath.row];
	cell.titleLabel.text = video.videoTitle;
	cell.videoURL = video.videoURL;
	NSArray *components = [cell.videoURL componentsSeparatedByString:@"v="];
	if ([components count] != 0) {
	cell.videoIdentifier = components[1];
	}
	dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
	dispatch_async(queue, ^{
	XCDYouTubeClient *client = [XCDYouTubeClient new];
	[client getVideoWithIdentifier:cell.videoIdentifier completionHandler:^(XCDYouTubeVideo * _Nullable video, NSError * _Nullable error) {
	//This is the money shot right here
	[cell.thumbImageView sd_setImageWithURL:video.smallThumbnailURL placeholderImage:[UIImage imageNamed:@"youtube"]];
	}];
	});
	return cell;
	}
	//////////////////////
	//Without SDWebImage//
	//////////////////////
	- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
	//Using custom cell class myCell which has a UIImage thumbnail
	myCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell"];
	if (cell == nil) {
	cell = [[myCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"cell"];
	}
	cell.thumbnail.image = nil; // or cell.poster.image = [UIImage imageNamed:@"placeholder.png"];
	//GDC queue
	dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
	dispatch_async(kBgQueue, ^{
	NSData *imgData = [NSData dataWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:@"http://myurl.com/%@.jpg"]]];
	if (imgData) {
	UIImage *image = [UIImage imageWithData:imgData];
	if (image) {
	dispatch_async(dispatch_get_main_queue(), ^{
	myCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
	if (updateCell)
	updateCell.thumbnail.image = image;
	});
	}
	}
	});
	return cell;
	}
	//Other example using YouTube API for grabbing thumbs
	- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
	{
	//Custom VideoCell class
	static NSString *CellIdentifier = @"VideoCell";
	VideoCell *cell = (VideoCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
	if (cell == nil)
	{
	cell = [[VideoCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
	}
	//VideoObject holds videoTitle, videoURL
	VideoObject *video = [VideoObject new];
	video = [self.safetyVideos objectAtIndex:indexPath.row]; //Array of videos already loaded
	cell.titleLabel.text = video.videoTitle;
	cell.videoURL = video.videoURL;
	//Grabbing the ID of the video from the URL
	NSArray *components = [cell.videoURL componentsSeparatedByString:@"v="];
	if ([components count] != 0) {
	cell.videoIdentifier = components[1];
	}
	//Setting placeholder image
	[cell.thumbImageView setImage:[UIImage imageNamed:@"youtube"]];
	//GDC queue
	dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
	dispatch_async(queue, ^{
	XCDYouTubeClient *client = [XCDYouTubeClient new];
	[client getVideoWithIdentifier:cell.videoIdentifier completionHandler:^(XCDYouTubeVideo * _Nullable video, NSError * _Nullable error) {
	//Setting everything up like in the above example
	NSData *data = [NSData dataWithContentsOfURL:video.smallThumbnailURL]; //YouTube API has thumbs/image/etc for XCDYouTubeVideo objects
	if (data) {
	UIImage *image = [UIImage imageWithData:data];
	if (image) {
	dispatch_async(dispatch_get_main_queue(), ^{
	VideoCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
	if (updateCell)
	updateCell.thumbImageView.image = image;
	});
	}
	}
	}];
	});
	return cell;
	}

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Weak Self Objective-C in Blocks

	@implementation XYZBlockKeeper
	- (void)configureBlock {
	self.block = ^{
	[self doSomething]; // capturing a strong reference to self
	// creates a strong reference cycle
	};
	}
	...
	@end
	/*
	It’s best practice to capture a weak reference to self, like this:
	*/
	- (void)configureBlock {
	XYZBlockKeeper * __weak weakSelf = self;
	self.block = ^{
	[weakSelf doSomething]; // capture the weak reference
	// to avoid the reference cycle
	}
	}

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Saving Data to NSUserDefaults

	// Given `notes` contains an array of Note objects
	//Archive
	NSData *data = [NSKeyedArchiver archivedDataWithRootObject:notes];
	[[NSUserDefaults standardUserDefaults] setObject:data forKey:@"notes"];
	//Unarchive
	NSData *notesData = [[NSUserDefaults standardUserDefaults] objectForKey:@"notes"];
	NSArray *notes = [NSKeyedUnarchiver unarchiveObjectWithData:notesData];

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