Add ASViewController and update Multiplex sample to use it.

examples/Multiplex/Sample/ViewController.m

@@ -10,77 +10,39 @@
  */
 
 #import "ViewController.h"
+#import "ScreenNode.h"
 
-#import <AsyncDisplayKit/AsyncDisplayKit.h>
-
-
-@interface ViewController () <ASMultiplexImageNodeDataSource, ASMultiplexImageNodeDelegate, ASImageDownloaderProtocol>
-{
-  ASMultiplexImageNode *_imageNode;
-
-  UILabel *_textLabel;
+@interface ViewController() {
+  ScreenNode *_screenNode;
 }
 
 @end
 
-
 @implementation ViewController
 
 - (instancetype)init
 {
-  if (!(self = [super init]))
+  ScreenNode *node = [[ScreenNode alloc] init];
+  if (!(self = [super initWithNode:node]))
     return nil;
 
-
-  // multiplex image node!
-  // NB:  we're using a custom downloader with an artificial delay for this demo, but ASBasicImageDownloader works too!
-  _imageNode = [[ASMultiplexImageNode alloc] initWithCache:nil downloader:self];
-  _imageNode.dataSource = self;
-  _imageNode.delegate = self;
-
-  // placeholder colour
-  _imageNode.backgroundColor = ASDisplayNodeDefaultPlaceholderColor();
-
-  // load low-quality images before high-quality images
-  _imageNode.downloadsIntermediateImages = YES;
-
-
-  // simple status label
-  _textLabel = [[UILabel alloc] init];
-  _textLabel.textAlignment = NSTextAlignmentCenter;
-  _textLabel.font = [UIFont fontWithName:@"HelveticaNeue-Light" size:22.0f];
+  _screenNode = node;
 
   // tap to reload
   UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(reload:)];
-  [_textLabel addGestureRecognizer:gr];
-
+  [_screenNode.textNode.view addGestureRecognizer:gr];
 
   return self;
 }
 
-- (void)viewDidLoad
+- (void)viewWillAppear:(BOOL)animated
 {
-  [super viewDidLoad];
-
-  [self.view addSubnode:_imageNode];
-  [self.view addSubview:_textLabel];
-
-  [self start];
+  [super viewWillAppear:animated];
+  [_screenNode start];
 }
 
-- (void)viewWillLayoutSubviews
-{
-  static CGFloat padding = 40.0f;
-
-  // lay out image
-  CGFloat imageWidth = self.view.bounds.size.width - padding;
-  CGPoint imageOrigin = CGPointMake(roundf((self.view.bounds.size.width - imageWidth) / 2.0f),
-                                    roundf((self.view.bounds.size.height - imageWidth) / 2.0f));
-  _imageNode.frame = (CGRect){ imageOrigin, CGSizeMake(imageWidth, imageWidth) };
-
-  // label
-  CGSize textSize = [_textLabel sizeThatFits:CGSizeMake(self.view.bounds.size.width, FLT_MAX)];
-  _textLabel.frame = CGRectMake(0.0f, imageOrigin.y + imageWidth + padding, self.view.bounds.size.width, textSize.height);
+- (void)reload:(id)sender {
+  [_screenNode reload];
 }
 
 - (BOOL)prefersStatusBarHidden
@@ -88,95 +50,4 @@
   return YES;
 }
 
-- (void)start
-{
-  _textLabel.text = @"loading…";
-  _textLabel.userInteractionEnabled = NO;
-
-  _imageNode.imageIdentifiers = @[ @"best", @"medium", @"worst" ]; // go!
-}
-
-- (void)reload:(id)sender {
-  [self start];
-  [_imageNode reloadImageIdentifierSources];
-}
-
-
-#pragma mark -
-#pragma mark ASMultiplexImageNode data source & delegate.
-
-- (NSURL *)multiplexImageNode:(ASMultiplexImageNode *)imageNode URLForImageIdentifier:(id)imageIdentifier
-{
-  if ([imageIdentifier isEqualToString:@"worst"]) {
-    return [NSURL URLWithString:@"https://raw.githubusercontent.com/facebook/AsyncDisplayKit/master/examples/Multiplex/worst.png"];
-  }
-
-  if ([imageIdentifier isEqualToString:@"medium"]) {
-    return [NSURL URLWithString:@"https://raw.githubusercontent.com/facebook/AsyncDisplayKit/master/examples/Multiplex/medium.png"];
-  }
-
-  if ([imageIdentifier isEqualToString:@"best"]) {
-    return [NSURL URLWithString:@"https://raw.githubusercontent.com/facebook/AsyncDisplayKit/master/examples/Multiplex/best.png"];
-  }
-
-  // unexpected identifier
-  return nil;
-}
-
-- (void)multiplexImageNode:(ASMultiplexImageNode *)imageNode didFinishDownloadingImageWithIdentifier:(id)imageIdentifier error:(NSError *)error
-{
-  _textLabel.text = [NSString stringWithFormat:@"loaded '%@'", imageIdentifier];
-
-  if ([imageIdentifier isEqualToString:@"best"]) {
-    _textLabel.text = [_textLabel.text stringByAppendingString:@".  tap to reload"];
-    _textLabel.userInteractionEnabled = YES;
-  }
-}
-
-
-#pragma mark -
-#pragma mark ASImageDownloaderProtocol.
-
-- (id)downloadImageWithURL:(NSURL *)URL
-             callbackQueue:(dispatch_queue_t)callbackQueue
-     downloadProgressBlock:(void (^)(CGFloat progress))downloadProgressBlock
-                completion:(void (^)(CGImageRef image, NSError *error))completion
-{
-  // if no callback queue is supplied, run on the main thread
-  if (callbackQueue == nil) {
-    callbackQueue = dispatch_get_main_queue();
-  }
-
-  // call completion blocks
-  void (^handler)(NSURLResponse *, NSData *, NSError *) = ^(NSURLResponse *response, NSData *data, NSError *connectionError) {
-    // add an artificial delay
-    usleep(1.0 * USEC_PER_SEC);
-
-    // ASMultiplexImageNode callbacks
-    dispatch_async(callbackQueue, ^{
-      if (downloadProgressBlock) {
-        downloadProgressBlock(1.0f);
-      }
-
-      if (completion) {
-        completion([[UIImage imageWithData:data] CGImage], connectionError);
-      }
-    });
-  };
-
-  // let NSURLConnection do the heavy lifting
-  NSURLRequest *request = [NSURLRequest requestWithURL:URL];
-  [NSURLConnection sendAsynchronousRequest:request
-                                     queue:[[NSOperationQueue alloc] init]
-                         completionHandler:handler];
-
-  // return nil, don't support cancellation
-  return nil;
-}
-
-- (void)cancelImageDownloadForIdentifier:(id)downloadIdentifier
-{
-  // no-op, don't support cancellation
-}
-
 @end