How to handle a custom URL in an already-open app? - iphone

I have an app based on the Utility template (i.e. Main and Flip view controllers). The Flip view allows selecting a certain item to be used on the main view. So far - works great.
Now I tried adding a custom URL. Something to the effect of: myapp://itemID=40 that will basically tell the main view: "no need to flip - you'll be dealing with item 40".
I registered the URL type scheme as "myapp" and added the following method to the app delegate:
- (BOOL)application:(UIApplication *)application handleOpenURL:(NSURL *)url {
if (!url) {
return NO;
}
NSString *urlString = [url absoluteString];
NSLog(#"URL received: %#", urlString);
NSString *itemID = [urlString stringByReplacingOccurrencesOfString:#"myapp://itemID=" withString:#""];
NSLog(#"Item received: %#", itemID);
[_mainViewController setStartupItem:itemID];
return YES;
}
As you can see, the itemID is set to a property called startupItem in the mainViewController.
I then added one line to the regular application method to verify that startupItem will be nil in case of no URL:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//Make sure URL string is empty
[_mainViewController setStartupItem:nil];
// Override point for customization after application launch.
// Add the main view controller's view to the window and display.
self.window.rootViewController = self.mainViewController;
[self.window makeKeyAndVisible];
return YES;
}
And in MainViewController.m I added code to handle the item to the viewDidLoad event.
And here's my problem: this scheme works great if the app is started from a URL the first time. If it's already running, then we never reach viewDidLoad again and therefore don't handle that particular item, but go on as if none was passed.
My humble question is: which UIViewController should I put my handling code in? Or, am I approaching all this the wrong way? Should this be handled in my model?
As always, thanks in advance for your time!
Guy

I would take a look at the docs for UIApplicationDelegate protocol, specifically;
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
And this which is deprecated.
- (BOOL)application:(UIApplication *)application handleOpenURL:(NSURL *)url

Well definitely not in a method that gets called only once while the application starts up! You need to refactor the item handling code in its own method, then call this method from viewDidLoad (once during startup) and handleOpenURL each time it gets called.

Related

Parse.com Facebook Login stays on "Loading" iOS

I'm using Parse, with the LogInViewController. I added Facebook on the logIn View.
When someone wants to connect with Facebook, it opens the browser, the user accepts the application and then he returns to the app. But when he returns on the app, he stays on "loading" and nothing happens.
However if the user restart the app, it works.
Only when it's the first connexion for the user I have this problem.
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
if (![PFUser currentUser]) {
// Customize the Log In View Controller
PFLogInViewController *logInViewController = [[PFLogInViewController alloc] init];
[logInViewController setDelegate:self];
[logInViewController setFacebookPermissions:[NSArray arrayWithObjects:#"friends_about_me", nil]];
[logInViewController setFields: PFLogInFieldsFacebook | PFLogInFieldsDismissButton];
// Present Log In View Controller
[self presentViewController:logInViewController animated:YES completion:NULL];
}
}
I think the problem isn't in my code because I use the default code of Parse but I'm not sure.
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {
return [FBAppCall handleOpenURL:url
sourceApplication:sourceApplication
withSession:[PFFacebookUtils session]];
}
- (void)applicationDidBecomeActive:(UIApplication *)application {
/*
Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
*/
[FBAppCall handleDidBecomeActiveWithSession:[PFFacebookUtils session]];
}
- (void)applicationWillTerminate:(UIApplication *)application {
/*
Called when the application is about to terminate.
Save data if appropriate.
See also applicationDidEnterBackground:.
*/
[[PFFacebookUtils session] close];
}

Inter-App Communication

I have an application that accepts input from the user. The information is used to create a query string which is forwarded to a second application using a custom URL scheme. The second application is opened as expected, but the application:openURL method in the AppDelegate of the 2nd application is never visited. Attached is the code from this method:
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
ProcessorViewController *viewController = (ProcessorViewController *)[mainStoryboard instantiateViewControllerWithIdentifier:#"ProcessorController"];
return [viewController handleURL:url];
}
Any assistance determining why this method in the app delegate is never visited would be greatly appreciated.

network activity indicator is not shown on iPhone (iOS 5)

just to test it I enabled the activity indicator of the status bar as follows:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible: TRUE];
//...
}
I never disable the indicator so it should always be visible, but it isn't. It is visible in the iPhone Simulator but not on the device. Why?
Please not that the application is not active when a call is made to didFinishLaunchingWithOptions. You should move this to the viewDidLoad method instead. Thus the code should look like this:
- (void)viewDidLoad {
[[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];
// Some other code goes here...
[super viewDidLoad];
}
Or you could put this code anywhere else where the view has been loaded. Do not forget to stop it once the data has been loaded.

Opening in app, getting UIApplicationLaunchOptionsURLKey from launchOptions

I'm trying to open a .pdf-file in my app. I adapted the Info.plist so a .pdf can be opened in my application.
I use the following code:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
thePDFurl = (NSURL *)[launchOptions valueForKey:UIApplicationLaunchOptionsURLKey];
return YES;
}
In an other class, where my appDelegate (containing that didFinishLaunchingWithOptions), I've got the line:
appDel = [[UIApplication sharedApplication]delegate];
[theLabel setText:[NSString stringWithFormat:#"%#", appDel.thePDFurl]];
Somehow, theLabel always shows (null). What am I missing?
I may be misunderstanding what you're trying to do. If so, ignore.
If you want the user to be able to "Open with..." a PDF using your app, you can implement
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
E.g.
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
NSLog(#"Open URL:\t%#\n"
"From source:\t%#\n"
"With annotation:%#",
url, sourceApplication, annotation);
NSString *filepath = [url path];
//...
return YES;
}
I'm pretty sure this works for both launching the app and calling it (i.e. if it's already in the background).
You may retain the pdfurl variable and also get the absolute string value from NSURL using the absoluteString method.
[theLabel setText:[NSString stringWithFormat:#"%#", [appDel.thePDFurl absoluteString]]]
I guess you were all right. It just so happened the view got loaded before the method applicationDidFinishLaunching was finished. Thanks all...
When you are calling within application:didFinishLaunchingWithOptions: ,
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
[viewController view] was implicitly called and there was no appDel.thePDFurl assigned yet.

How to use [[UIApplication sharedApplication] openURL:] open other app?

I followed http://iosdevelopertips.com/cocoa/launching-your-own-application-via-a-custom-url-scheme.html instruction to open app1(GlassButton) within app2(FontTest).
The open method of FontTest as following:
-(void)open {
BOOL res = [[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:#"glassbutton://"]];
if (res) {
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:#"glassbutton://"]];
}
}
The value of "res" is "YES", but nothing happen after openURL method be called.
The info-list of "FontTest"as following:
URL Schemes: glassbutton
URL identifier: com.yourcompany.glassbutton
I tried to open twitter and facebook apps by "twitter://" and "fb://" successfully. But I do not know why I cannot open this small app. I'm not sure whether any thing/step wrong or missing? Need I handle - (BOOL)application:(UIApplication *)application handleOpenURL:(NSURL *)url for FontTest, if yes, how to handle it? Could you please kindly help me? Thanks in advance!
To request the launch of your app use something like this:
NSString *urlString= #"glassbutton://com.yourcompany.glassbutton";
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:urlString]];
Then, in the glassbutton app, you'll need to handle any special behavior within the app delegate method:
- (BOOL)application:(UIApplication *)application handleOpenURL:(NSURL *)url {
//your app specific code here for handling the launch
return YES;
}
Note that within the app you are opening the above delegate method will only get called AFTER the following method is called:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
Handle accordingly, good luck.