Exclude external javascript content from UIWebView delegate methods - uiwebview

I have a UIWebview with delegate methods
webViewDidStartLoad
webViewDidFinishLoad
However, on the page I am loading a facebook chat component which for whatever reason is failing to properly load (cache problem? problem with fb?) And it is hitting the server over and over cause my two delegate metods to be called over and over (the only thing they are used for is showing and hiding an activity indicator and therefore I left with a blinking activity indicator)
Is there anyway to stop calling these methods when the page has loaded but is still "trying" to load external content that I do not have control over?
- (void)webViewDidStartLoad:(UIWebView *)webView {
NSLog(#" I am in Webview did start");
if ( webView == self.myFlickView )
{
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
}
}
- (void)webViewDidFinishLoad:(UIWebView *)webView {
NSLog(#" I am in Webview did end");
if ( webView == self.myFlickView )
{
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
}
}

Try setting the delegate to nil at webViewDidFinishLoad. The delegate is probably being called several times due to AJAX calls in the web site loaded. So, use [webView setDelegate:nil].
Hope it helps.

Related

Branch Universal Deep Link does not display custom view controller elements

So I have a Universal link that leads to a view controller in my app. On that particular view controller I display a couple of images as well as a web view. The webView displays a url chosen by the user. How do I save this custom url so that it is displayed every time someone clicks the link? I think the code to this is under:
#synthesize deepLinkingCompletionDelegate;
-(void)configureControlWithData:(NSDictionary *)data {
NSString *string = data[#"favoriteArticle"];
Alex from Branch.io here:
To accomplish this, you need to do two things.
Step 1
Store the URL of the article you want to load as one of the Branch link custom parameters. Full instructions on how to do that here, but essentially:
BranchUniversalObject *branchUniversalObject = [[BranchUniversalObject alloc] initWithCanonicalIdentifier:#"item/12345"];
branchUniversalObject.title = #"My Content Title";
branchUniversalObject.contentDescription = #"My Content Description";
branchUniversalObject.imageUrl = #"https://example.com/mycontent-12345.png";
[branchUniversalObject addMetadataKey:#"favorite_article" value:#"https://example.com/path/to/article"]; // this is used to route inside the app
[branchUniversalObject addMetadataKey:#"property2" value:#"red"];
BranchLinkProperties *linkProperties = [[BranchLinkProperties alloc] init];
linkProperties.feature = #"sharing";
linkProperties.channel = #"facebook";
[linkProperties addControlParam:#"$desktop_url" withValue:#"https://example.com/path/to/article"]; // this is used for desktop visitors
[linkProperties addControlParam:#"$ios_url" withValue:#"https://example.com/path/to/article"]; // this is used for iOS mobile visitors without the app installed
Step 2
Then when the app opens after a link click, watch for that data key. Again, full instructions, but basically:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// initialize the session, setup a deep link handler
[[Branch getInstance] initSessionWithLaunchOptions:launchOptions
andRegisterDeepLinkHandler:^(NSDictionary *params, NSError *error) {
// start setting up the view controller hierarchy
UINavigationController *navC = (UINavigationController *)self.window.rootViewController;
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *nextVC;
// If the key 'favoriteArticle' is present in the deep link dictionary
// then load the picture screen with the appropriate picture
NSString * favoriteArticle = [params objectForKey:#"favorite_article"];
if (favoriteArticle) {
nextVC = [storyboard instantiateViewControllerWithIdentifier:#"ArticleVC"];
[nextVC setArticleUrl: favoriteArticle];
} else {
nextVC = [storyboard instantiateViewControllerWithIdentifier:#"MainVC"];
}
// navigate!
[navC setViewControllers:#[nextVC] animated:YES];
}];
return YES;
}
After this, in your ArticleVC, retrieve the favoriteArticle value and use it for your webview.
Step 2 (Alternate)
The configureControlWithData method you mentioned is used in the automatic deep link routing implementation. You may be able to adapt this to work with a webview, but I haven't personally tried that. It would look something like this:
#synthesize deepLinkingCompletionDelegate;
- (void)configureControlWithData:(NSDictionary *)data {
NSString *favoriteArticle = data[#"favorite_article"];
// load the webview with the URL stored inside favoriteArticle
}

Mysterious action on page in iOS WKWebView, which doesn't trigger any callbacks

I have a web page with a button which triggers some action and I want to show "back" button on the UI when the web view can go back. This action is handled properly by desktop browser and swiping gestures on the webview (i.e. browser shows the back button and swiping back works properly). But for some reason, this action doesn't trigger any WKNavigationDelegate callbacks. Webview and following callbacks look to be setup properly in the VC:
webView.navigationDelegate = self
decidePolicyForNavigationAction
didStartProvisionalNavigation
didFinishNavigation
didReceiveServerRedirectForProvisionalNavigation
didFailNavigation
didCommitNavigation
webViewWebContentProcessDidTerminate
didReceiveAuthenticationChallenge
didFailProvisionalNavigation
Even using observer for "loading" property of the web view doesn't work:
webView.addObserver(self, forKeyPath: "loading", options: .New, context: nil)
override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>) {
guard let _ = object as? WKWebView else { return }
guard let keyPath = keyPath else { return }
guard let change = change else { return }
switch keyPath {
case "loading":
// Set button
default:break
}
Callbacks for other actions on the same website work properly.
What can be the reason for this?

Threading issue with UICollectionview loading images from CloudKit

I'm having a threading issue loading images in a collectionview where the data is coming from cloudkit. I know this is a threading/blocking issue because before I implemented CK, I dumped some images in a folder on my desktop and read/parsed them from there and had no issue. With CK, I just created a handful of records via the dashboard and I'm successfully getting the expected records returned and use the images from those results to populate the CV cells. I store the CK query results in an array and use the size of that array to set the numberOfItemsInSection delegate.
Here's the issue...in the numberOfItemsInSection delegate method, I'm calling the model class, which executes the CK query. Since that is obviously a network call, I put that in a background thread. From logging, I can see the query execute and the results come back very quickly - within 2-3 seconds. However, the CV cells never display and I don't see the custom cell get initialized (via logging). But if I tap the camera button and take a photo, which I've implemented, I take the resulting image and add it to the array, then call reloadData on the CV and all the cells (and images) appear, including the new image just taken with the camera.
By accident, I found out a hack that somewhat works, which is calling reloadData on the CV inside the background thread of the numberOfItemsInSection delegate method. As a result, I thought I might have stumbled on to the solution by switching back to the main thread when calling reloadData, but that put it in a sort of endless loop of continuously calling the numberOfItemsInSection method and cellForItemAtIndexPath and made it to where it lagged to a point that you could barely scroll and tapping on any of the cells wouldn't do anything.
At this point, after trying many, many various things, I'm at a complete loss on how to fix this. I know this is probably a pretty easy solution as it's very common to load images asynchronously to populate a collectionview or tableview. Can someone please provide some guidance? Thanks in advance!!!
#property (nonatomic) NSInteger numberOfItemsInSection;
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
NSLog(#"***numberOfItemsInSection***");
dispatch_queue_t fetchQ = dispatch_queue_create("load image data", NULL);
dispatch_async(fetchQ, ^{
self.numberOfItemsInSection = [self.imageLoadManager.imageDataArray count];
[self.myCollectionView reloadData]; // should be done on main thread!
});
NSLog(#"numberOfItemsInSection: %ld", (long)self.numberOfItemsInSection);
return self.numberOfItemsInSection;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell"; // string value identifier for cell reuse
ImageViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier forIndexPath:indexPath];
NSLog(#"cellForItemAtIndexPath: section:%ld row:%ld", (long)indexPath.section, (long)indexPath.row);
cell.layer.borderWidth = 1.0;
cell.layer.borderColor = [UIColor grayColor].CGColor;
cell.imageView.contentMode = UIViewContentModeScaleAspectFit;
ImageData *imageData = [self.imageLoadManager imageDataForCell:indexPath.row]; // maps the model to the UI
dispatch_async(dispatch_get_main_queue(), ^{
if (imageData.imageURL.path) {
cell.imageView.image = [UIImage imageWithContentsOfFile:imageData.imageURL.path];
[cell setNeedsLayout];
} else {
// if imageURL is nil, then image is coming in from the camera as opposed to the cloud
cell.imageView.image = imageData.image;
[cell setNeedsLayout];
}
});
return cell;
}
before returning self.numberOfItemsInSection you should wait until the async call is finished. You can do that using semaphores. But then why are you doing this async? You are just getting the count of an array. And then you shouldn't reloadData there. Where do you start your CloudKit query? are you doing that onViewDidLoad? That is also an async operation. When that completes just doe a reloadData of your collectionView. Besides that doing this would be enough:
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
return [self.imageLoadManager.imageDataArray count];
}
If you really want to use async there, then you do have to wait for the result. You could change your code to something like:
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
NSLog(#"***numberOfItemsInSection***");
dispatch_semaphore_t sema = dispatch_semaphore_create(0);
dispatch_queue_t fetchQ = dispatch_queue_create("load image data", NULL);
dispatch_async(fetchQ, ^{
self.numberOfItemsInSection = [self.imageLoadManager.imageDataArray count];
[self.myCollectionView reloadData]; // should be done on main thread!
dispatch_semaphore_signal(sema);
});
NSLog(#"numberOfItemsInSection: %ld", (long)self.numberOfItemsInSection);
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
return self.numberOfItemsInSection;
}
And then why do you go to the main queue in cellForItemAtIndexPath? It's already executed on the main queue.

Tap Detecting Window and Two View Controllers

I'm rather new to iOS development and for my first real app I'm using a TapDetectingWindow to detect touches on a UIWebView (exactly as detailed on http://mithin.in/2009/08/26/detecting-taps-and-events-on-uiwebview-the-right-way).
I used it in one View Controller as suggested with a reference in the header file and the following in the implementation file;
- (void)viewDidLoad {
[super viewDidLoad];
mWindow = (TapDetectingWindow *)[[UIApplication sharedApplication].windows objectAtIndex:0];
mWindow.viewToObserve = igWeb;
mWindow.controllerThatObserves = self;
- (void)userDidTapWebView:(NSArray *)tapPoint {
}
It worked perfectly.
Now the problem is that I would like to use the TapDetectingWindow in a second View Controller.
I copied the same code from the first view controller (only changing the name of the viewToObserve).
Now, when I run the app. The Tap Detecting window works fine in the first ViewController, then works fine when you go to the second View Controller but when you go back to the first view controller its broken until the view gets loaded again.
Please help.
try something like
-(void)viewWillAppear:(BOOL)animated
{
mWindow.viewToObserve = igWeb;
mWindow.controllerThatObserves = self;
[super viewWillAppear:animated];
}

How to "preload" view controller without actually pushing it?

Background:
I've got a free app that is ad-supported. The basic idea is that when the app is launched, ad content (HTML) is downloaded from the server in the background, and only if the download was successful, then the content is being shown.
Previous solution:
I have implemented this successfully in a universal app. Originally, I loaded a NSData variable with an URL, and if it was successful, then I presented a modal view which contained an UIWebView (relevant code is in another question). The problem is that the external assets (images) don't get loaded in the original NSData request, so in a stroke of genius I thought of another way:
New solution:
The new way, and this is what I want help with, is that I'm instantiating the modal view controller (without displaying it yet), and having the web view begin loading the URL directly. When the webViewDidFinishLoad method is called, I fire a notification back to the parent which then performs the presentModalViewController.
Here are the methods which instantiate the view controller and present it modally:
- (void)launchAd
{
if ([ServerCheck serverReachable:#"openx.freewave-wifi.com" hideAlert:YES])
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(presentAdModal) name:#"AdLoaded" object:nil];
AdViewController *adView = [[AdViewController alloc] initWithNibName:nil bundle:nil];
[[adView view] awakeFromNib]; //THIS LINE IS WHAT THIS QUESTION IS ABOUT
navController = [[UINavigationController alloc] initWithRootViewController:adView];
[adView release], adView = nil;
[navController setModalPresentationStyle:UIModalPresentationFormSheet];
[navController setModalTransitionStyle:UIModalTransitionStyleCoverVertical];
[[navController navigationBar] setTintColor:[UIColor colorWithRed:0.94 green:0.00 blue:0.32 alpha:1.00]];
}
else
LogError(#"Not presenting ad.");
}
- (void)presentAdModal
{
LogInfo(#"Presenting advertisement modal.");
[[NSNotificationCenter defaultCenter] removeObserver:self name:#"AdLoaded" object:nil];
[tabBarController presentModalViewController:navController animated:YES];
[navController release];
}
And in the AdView controller:
- (void)webViewDidFinishLoad:(UIWebView *)theWebView
{
LogInfo(#"Ad content did load; we can show it.");
[timeout invalidate], timeout = nil;
[self setTitle:#"From Our Sponsor"];
[[NSNotificationCenter defaultCenter] postNotificationName:#"AdLoaded" object:nil];
}
Now what's above does work. However, it took a long time for me to figure out how to cause the view controller delegate methods in the AdView controller to fire before calling presentModalViewController. I did this by adding [[adView view] awakeFromNib];, but I know this isn't the right way to make this happen.
So, everything above does work beautifully, effectively having the view controller and its UIWebView "preload" before displaying it. I just want to know what I should be doing instead of [[adView view] awakeFromNib]; -- I want to do it the right way.
Or is this right? I guess some folks would say "If it works, then it's right", but I know this isn't true.

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