NSURLConnection to check periodic updates on the server - ios

I have a function "downLoadButtonStatusSetter" which is called every 15 seconds with a timer.
It then calls sends "sendInstantGetInfoRequest" data to the server and checks whether the connection is available, and sets a flag.
The application is working properly, but gets into a busy state for a while when it fails to connect to the server.
How should i call these methods so that "It gets called every 15 seconds AND sets the flags even though it fails to connect to the server,
without affecting the main execution of the program. I have tried a combination of thread callings , but cannot, please help.
The timer calling code:
updateCheckTimer= [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:#selector(downLoadButtonStatusSetter) userInfo:nil repeats:YES];
ButtonStatusSetter Code:
-(BOOL) downLoadButtonStatusSetter
{
[self sendInstantGetInfoRequest];
if( instantGetInfoOffLineForButton)
{
//setbutton color etc....
}
}
-(NSArray *)sendInstantGetInfoRequest
{
NSString *getInfoURL=[SAGlobal getInfoURL];
NSArray *keys = [NSArray arrayWithObjects:#"username",#"password", nil];
NSArray *objects = [NSArray arrayWithObjects:SharedAppDelegatee.SAloginName, SharedAppDelegatee.SAloginPassword, nil];
jsonManager = [[JsonRequestManager alloc] init];
SAJSonResult* resultk=[jsonManager sendJsonAsPOSTData: keys AndValues:objects toURL: getInfoURL];
if(resultk.jsonError)
{
instantGetInfoOffLineForButton=true;
}
else{
instantGetInfoOffLineForButton=false;
}
return resultk.jsonResult;
}
The JSON request sending code:
-(SAJSonResult *) sendJsonAsPOSTData:(NSArray *) keys AndValues:(NSArray *) values toURL:(NSString *)anURL
{
////..................
NSURL *url1 = [NSURL URLWithString:anURL];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url1];
[request setHTTPMethod:#"POST"];
[request setHTTPBody: jsonData];
[request setValue:#"application/json" forHTTPHeaderField:#"Content-Type"];
[request setValue:[NSString stringWithFormat:#"%d", [jsonData length]] forHTTPHeaderField:#"Content-Length"];
NSURLResponse *theResponse =[[NSURLResponse alloc]init];
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&theResponse error:&jsonError];
if (jsonError) {
..............
return jResult;
}
else
{
...............
return jResult;
}
}
}

Related

login and completion handler

I'm developing an app with a login page. When the app is launched, the login screen is shown, and you cannot access the app until you are connected. To connect to the app, you enter your username and your password. When you press the "connect" button, json data containing the username and password is sent to a web service, which check if the credentials exists. If they exists, the server send a json file containing "exists":"true"
The problem is that the code checking this Json file is in completionHandler of my NSURLSession, and the method return "NO" before the Json data is checked, so I can not connect to my app. As it's hard to explain, here is my code:
GSBconnexion.m:
#import "GSBconnexion.h"
#implementation GSBconnexion
-(bool)logConnexionWithUserName:(NSString *)username
password:(NSString *)password{
__block BOOL allowConnexion;
NSDictionary *connexion = #{
#"username": username,
#"password": password,
#"target": #"app"
};
NSError *error;
NSData *jsonLogData = [NSJSONSerialization dataWithJSONObject:connexion options:NSJSONWritingPrettyPrinted
error:&error];
if (! jsonLogData) {
NSLog(#"Got an error: %#", error);
}
NSData *logData = jsonLogData;
NSString *testString = [[NSString alloc] initWithData:logData encoding:NSUTF8StringEncoding];
NSString *logLength = [NSString stringWithFormat:#"%lu", (unsigned long)[testString length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:#"http://192.168.5.133:1337/login"]];
[request setHTTPMethod:#"POST"];
[request setValue:logLength forHTTPHeaderField:#"Content-lenght"];
[request setValue:#"application/json" forHTTPHeaderField:#"Accept"];
[request setValue:#"application/json" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:logData];
NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
[[session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error){
NSDictionary *serverResponse = [NSJSONSerialization JSONObjectWithData:data options:
NSJSONReadingMutableContainers error:&error];
int canIConnect = [serverResponse[#"exist"] intValue];
NSLog(#"%d",canIConnect);
if (canIConnect == 1) {
NSLog(#"OKKK");
allowConnexion = YES;
NSString *sessionID = [[NSString alloc]initWithString:serverResponse[#"_id"]];
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setObject:sessionID forKey:#"SessionID"];
[userDefaults synchronize];
NSLog(#"ID Session:%#",[userDefaults objectForKey:#"sessionID"]);
}
else {
allowConnexion=NO;
}
}] resume];
NSLog(#"JSON envoyé: \n\n%#",testString);
return allowConnexion;
}
#end
GSBLoginController:
- (IBAction)connect:(id)sender {
connectButton.hidden = YES;
loading.hidden = NO;
UIViewController* homePage = [self.storyboard instantiateViewControllerWithIdentifier:#"homePage"];
GSBconnexion *login = [[GSBconnexion alloc]init];
NSString *username = [[NSString alloc]initWithFormat:#"%#",usernameTextField.text];
NSString *password = [[NSString alloc]initWithFormat:#"%#",pwdTextField.text];
BOOL authorized = [login logConnexionWithUserName:username password:password];
if (authorized) {
[self presentViewController:homePage animated:YES completion:nil];
}
else {
connectButton.hidden = NO;
loading.hidden=YES;
usernameTextField.text=#"";
pwdTextField.text=#"";
errorLabel.text = #"Connexion impossible, merci de réessayer.\nSi le problème persiste, veuillez contacter un administrateur.";
}
NSLog(authorized ? #"Yes" : #"No");
}
I hope you understood me, thanks for your help!
Simon
The problem is that you're expecting a return value from a method that is executing asynchronously. So basically return allowConnexion is happening immediately even though the dataTask is still ongoing in the background. Thus, you're relying on an incorrect value. Basically what you want to do is copy what is happening in the dataTask w/ a completion handler.
So you could say something like typedef void (^CompletionBlock) (BOOL isFinished);
Then change your login method to include the completion block as its last argument and return nothing:
-(void)logConnexionWithUserName:(NSString *)username
password:(NSString *)password
withCompletion:(CompletionBlock)completionBlock
Then inside of the dataTask's completionHandler call the completionBlock passing in the value of allowConnexion.
Finally once you've done all that in your login view controller you'll implement this new method, and inside of the completion block you can update your view accordingly. Its going to look something like this:
- (void)thingWithCompletion:(CompletionBlock)completionBlock
{
dispatch_async(dispatch_get_main_queue(), ^{
completionBlock(YES);
});
}
- (void)viewDidLoad {
[super viewDidLoad];
[self thingWithCompletion:^(BOOL isFinished) {
//update UI
}];
}
Be advised that since you're on a background thread and going to update UI on completion you're going to want to dispatch to the main queue as well. That is why the call to completionBlock(YES); is wrapped in the dispatch_async call.

NSHTTPURLResponse release message sent to deallocated instance

I have the following code to get data from server;
-(void)loginForFaceBook
{
GTMOAuth2ViewControllerTouch *viewController;
viewController = [[GTMOAuth2ViewControllerTouch alloc]
initWithScope:#"https://www.googleapis.com/auth/plus.me"
clientID:#"27615...6qdi60qjmachs.apps.googleusercontent.com"
clientSecret:#"Fs8A...u2PH"
keychainItemName:#"OAuth2 Sample:
Google+"
delegate:self
finishedSelector:#selector(viewController:finishedWithAuth:error:)];
[[self navigationController] pushViewController:viewController
animated:YES];
}
- (void)viewController:(GTMOAuth2ViewControllerTouch *)viewController
finishedWithAuth:(GTMOAuth2Authentication *)auth
error:(NSError *)error {
if (error != nil) {
// Authentication failed (perhaps the user denied access, or closed the
// window before granting access)
NSLog(#"Authentication error: %#", error);
NSData *responseData = [[error userInfo] objectForKey:#"data"]; //
kGTMHTTPFetcherStatusDataKey
if ([responseData length] > 0) {
// show the body of the server's authentication failure response
// NSString *str = [[NSString alloc] initWithData:responseData
// encoding:NSUTF8StringEncoding];
// NSLog(#"%#", str);
}
// self.auth = nil;
} else {
// NSString *authCode = [NSString alloc]in;
NSMutableURLRequest * request;
request = [[NSMutableURLRequest alloc] initWithURL:[NSURL
URLWithString:#"http://api.kliqmobile.com/v1/tokens"]
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:60] ;
NSLog(#"%#",auth);
NSLog(#"ho gya success %# :::: %# :::: %#", auth.accessToken,
auth.refreshToken, auth.code);
NSMutableURLRequest * response;
NSError * error;
request.URL = [NSURL URLWithString:#"http://api.kliqmobile.com/v1/tokens"];
NSString *post = [NSString stringWithFormat:#"
{\"token\":\"%#\",\"secret\":\"%#\",\"service\":\"%#\",\"handle\":\"%#\"}",
auth.accessToken,auth.code,#"google",nil];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding
allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d",[postData length]];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded"
forHTTPHeaderField:#"Content-Type"];
[request setHTTPMethod:#"POST"];
[request setHTTPBody:postData];
error = nil;
response = nil;
NSURLConnection *connection = [NSURLConnection connectionWithRequest:request
delegate:self];
[connection start];
}
I have implemented the NSURLConnection delegtes method and data is printing well like this
- (void)connection:(NSURLConnection*)connection didReceiveData:(NSData*)data
{
NSMutableURLRequest * response;
NSError * error;
NSLog(#"Did Receive Data %#", [[NSString alloc]initWithData:data
encoding:NSUTF8StringEncoding]);
NSMutableURLRequest * requestContacts;
requestContacts = [[NSMutableURLRequest alloc] initWithURL:[NSURL
URLWithString:#"http://api.kliqmobile.com/v1/contacts"]
cachePolicy:NSURLRequestReloadIgnoringCacheData
timeoutInterval:60] ;
[requestContacts setHTTPMethod:#"GET"];
[requestContacts setAllHTTPHeaderFields:headers];
error = nil;
response = nil;
NSData* data1 = [NSURLConnection sendSynchronousRequest:requestContacts
returningResponse:&response error:&error];
NSLog(#"WE GET THE REQUIRED TOKAN DATA %# :: %# :: %#", [[NSString alloc]
initWithData:data1 encoding: NSASCIIStringEncoding], error ,response);
}
but after that my app get crashed and it is giving following error;
[NSHTTPURLResponse release]: message sent to deallocated instance 0xcb51070.
please suggest me how to do this.
A couple of thoughts:
What is the intent of your didReceiveData method? There are a bunch of issues here:
You really shouldn't be doing a synchronous network request in the middle of a NSURLConnectionDataDelegate method.
You shouldn't be doing synchronous requests at all, but rather do them asynchronously.
What is the connection between receiving data and your creation of this new request? You're not using the data in the request, so why do it here?
The typical pattern is:
The didReceiveResponse should instantiate a NSMutableData object in some class property.
The only function of didReceiveData should be to append the received data to the NSMutableData. Note, this method may be called multiple times before all the data is received.
In connectionDidFinishLoading, you should initiate any next steps that you take upon successful completion of the request. If you wanted to do start another asynchronous network request when the initial request is done, do that here.
In didFailWithError, you obviously handle any failure of the connection.
When you call connectionWithRequest, you should not use the start method. Only use start when you use initWithRequest:delegate:startImmediately: with NO for the startImmediately parameter. Otherwise the connection starts automatically for you and you're only starting it a second time.
Unrelated to your original question, but your creation of post string cannot be right. You're missing a parameter value. Even better, rather than creating JSON manually, use NSDictionary and then use NSJSONSerialization to make the NSData object containing the JSON from this dictionary. That's much safer:
NSDictionary *params = #{#"token" : auth.accessToken,
#"secret" : auth.code,
#"service" : #"google",
#"handle" : #""};
NSError *error;
NSData *postData = [NSJSONSerialization dataWithJSONObject:params options:0 error:&error];
Clearly, supply whatever you need for the handle value.
A tangential process-related observation, but I'm wondering if you're taking advantage of everything Xcode offers. For example, your declaration of response as a NSMutableURLRequest but then using that as a parameter to sendSynchronousRequest should have generated a compiler warning. The same thing is true with your stringWithFormat for your post string (my third point). That should have generated a warning, too.
Neither of these are immediately relevant, but I wonder if you are failing to heed any other compile-time warnings. These warnings are your best friend when writing robust code and I would recommend resolving all of them. To go a step further, you should also run the project through the static analyzer ("Analyze" on "Product" menu, or shift+command+B), and resolve anything it points out, too.

IOS Creating Utility Class For NSURL

I have a project I am working on that has a number of different news feeds and announcement boards that displays post from various sources. Currently I have the code for the like, delete and flag buttons in methods contained in each class file for the views that display the feeds. I have been trying to craft a utility class that allows me to place the code for the three functionalities listed above in one object to be used throughout the project. I have done the exact same type of thing in C++ or Java, but am having issues reproducing it in objective-c. The like, delete and flag buttons use the NSURL libraries to interact with the web service. Bellow is an example of one of the methods I am trying to implement in the utility class, and is the code used to be implemented in the like buttons:
+ (void)btnLikeAction:(UIButton *)btnLike userIdString:(NSString *)userId contentSource:(NSString *)sourceId cellUsed:(NewsfeedCell *)cell dataForCell:(Post *)post
{
BOOL hasLiked = post.hasLiked;
UILabel *likeLabel = cell.likeCount;
NSString *pId = post.postId;
if (hasLiked)
{
[btnLike setEnabled:NO];
NSString *url = [NSString stringWithFormat: #"http://192.155.94.183/api/v1/likes/unlike/%#/%#/%#/", sourceId, pId, userId];
NSURL *URL = [NSURL URLWithString:url];
NSURLRequest *request = [NSURLRequest requestWithURL:URL cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30.0];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[connection start];
int localCount = [likeLabel.text intValue];
localCount--;
likeLabel.text = [NSString stringWithFormat:#"%i", localCount];
post.likeCount = [NSString stringWithFormat:#"%i", localCount];
post.hasLiked = NO;
[btnLike setEnabled:YES];
}
else
{
[btnLike setEnabled:NO];
NSError *err = nil;
NSDictionary *likeData = [NSDictionary dictionaryWithObjectsAndKeys:
userId, #"user_id",
pId, #"source_id",
sourceId, #"source",
nil];
NSData *JSONLike = [NSJSONSerialization dataWithJSONObject:likeData options:NSJSONWritingPrettyPrinted error:&err];
NSString *url = #"http://192.155.94.183/api/v1/likes.json";
NSURL *URL = [NSURL URLWithString:url];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL
cachePolicy:NSURLRequestUseProtocolCachePolicy
timeoutInterval:30.0];
[request setHTTPMethod:#"POST"];
[request setValue:#"application/json" forHTTPHeaderField:#"Accept"];
[request setValue:#"application/json" forHTTPHeaderField:#"Content-Type"];
[request setValue:[NSString stringWithFormat:#"%d", [JSONLike length]] forHTTPHeaderField:#"Content-Length"];
[request setHTTPBody:JSONLike];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[connection start];
int localCount = [likeLabel.text intValue];
localCount++;
likeLabel.text = [NSString stringWithFormat:#"%i", localCount];
post.likeCount = [NSString stringWithFormat:#"%i", localCount];
post.hasLiked = YES;
[btnLike setEnabled:YES];
}
}
This code uses a web service to update the number of likes for a specific piece of content. It works when the method is placed into the individual ViewController class files, but when I try to make a utility class with the individual methods I run into issues with the didReceiveAuthenticationChallenge, didReceiveResponse, didReceiveData and connectionDidFinishLoading methods not being called. Originally, I assumed that the delegate methods would be called in the file that that the utility methods were called in. But that was not the case. When I implemented the method definitions in the actual utility class, the methods still weren't called. I did some research on the topic and looked into this article but found I was unable to find substantial resources that helped my specific situation. How do I set up my utility class? I can post the full code of the utility if needed.
As #serrrgi already said, the problem is that btnLikeAction:... is a class method, so that self is the class itself. You have the following options:
Make all delegate methods class methods, e.g.
+ (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
NSLog(#"didReceiveResponse");
}
Create an instance of your Utility class and use that as delegate:
YourClass *u = [[self alloc] init];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:u];
Use sendAsynchronousRequest:..., which does not need a delegate:
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
if (data != nil) {
NSLog(#"success");
} else {
NSLog(#"error: %#", error);
}
}];

How to enumerate through NSArray of NSDictionaries with a block call inside the loop?

I get an self.usersArray with 2 elements in the format:
(
{
userCreated = "2012-01-05 12:27:22";
username = Simulator;
},
{
userCreated = "2013-01-01 14:27:22";
username = "joey ";
}
)
This is gotten in a completion block after which I call another method to fetch points for these 2 users through a helper class:
-(void)getPoints{
self.usersPointsArray = [[NSMutableArray alloc] init];
for (NSDictionary *usersDictionary in self.usersArray) {
[SantiappsHelper fetchPointsForUser:[usersDictionary objectForKey:#"username"] WithCompletionHandler:^(NSArray *points){
if ([points count] > 0) {
[self.usersPointsArray addObject:[points objectAtIndex:0]];
}
NSLog(#"self.usersPointsArray %#", self.usersPointsArray);
}];
}
}
The final self.usersPointsArray log looks like:
(
{
PUNTOS = 5;
username = Simulator;
},
{
PUNTOS = 2;
username = joey;
}
)
But the problem is that the way the call for points is structured, the self.usersPointsArray is returned twice, each time with an additional object, due to the for loop, I know.
Here is the Helper class method:
+(void)fetchPointsForUser:(NSString*)usuario WithCompletionHandler:(Handler2)handler{
NSURL *url = [NSURL URLWithString:#"http://myserver.com/myapp/readpoints.php"];
NSDictionary *postDict = [NSDictionary dictionaryWithObjectsAndKeys:usuario, #"userNa", nil];
NSData *postData = [self encodeDictionary:postDict];
// Create the request
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:#"POST"];
[request setValue:[NSString stringWithFormat:#"%d", postData.length] forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/x-www-form-urlencoded charset=utf-8" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
__block NSArray *pointsArray = [[NSArray alloc] init];
dispatch_async(dispatch_get_main_queue(), ^{
// Peform the request
NSURLResponse *response;
NSError *error = nil;
NSData *receivedData = [NSURLConnection sendSynchronousRequest:request
returningResponse:&response
error:&error];
if (error) {
if ([response isKindOfClass:[NSHTTPURLResponse class]]) {
NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse*)response;
NSLog(#"HTTP Error: %d %#", httpResponse.statusCode, error);
return;
}
return;
}
NSString *responseString = [[NSString alloc] initWithData:receivedData encoding:NSUTF8StringEncoding];
pointsArray = [NSJSONSerialization JSONObjectWithData:[responseString dataUsingEncoding:NSASCIIStringEncoding] options:0 error:nil];
if (handler)
handler(pointsArray);
});
}
I cannot use the self.usersPointsArray with the initial objects, only with the finalized object. It wont always be 2 elements, i actually dont know how many it will be.
What would be the way to structure it so I get a final call when the self.usersPointsArray is complete and then I reload my tableview?
I think of your problem as a standard consumer-producer problem. You can create a queue count for the amount of items that will be processed (int totalToProcess=self.usersArray.count). Each time the completion handler is hit, it will do totalToProcess--. When totalToProcess reaches 0 you have processed all of the elements in your queue and can refresh your table.
If I understand your question correctly I believe this solves your problem. If not, hopefully I can with a bit more information.

Why loading data Indicator is not working properly?

In my code I am using an UIActivityIndicatorView on an UIAlertView. It is working fine but my problem is it is not showing up on correct time. I mean to say when the device get data from web service after that this loading indicator is appearing in the end and its not rite thing I think because I want it to be appear when the web service is sending or receiving data.
I need help as I am new to iOS app development. If there is any other easy way to do this thing then suggest me.
I hope my question is clear, my problem is according to this code the loading indicator is appearing after i get reply from web service but i want to run this indicator as the user will press update button and web service should be called after that. Tell me where i am wrong.
Here is the code I am using
-(IBAction)update:(id)sender
{
av=[[UIAlertView alloc] initWithTitle:#"Updating Image..." message:#"" delegate:self cancelButtonTitle:nil otherButtonTitles:nil];
ActInd=[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
[ActInd startAnimating];
[ActInd setFrame:CGRectMake(125, 60, 37, 37)];
[av addSubview:ActInd];
[av show];
{
NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];
int gid=[defaults integerForKey:#"gid"];
NSString *gameid=[NSString stringWithFormat:#"%i", gid];
NSLog(#"%#",gameid);
img=mainImage.image;
NSData *imgdata=UIImagePNGRepresentation(img);
NSString *imgstring=[imgdata base64EncodedString];
NSLog(#"%#",imgstring);
NSString *escapedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(
NULL,
(CFStringRef)imgstring,
NULL,
CFSTR("!*'();:#&=+$,/?%#[]"),
kCFStringEncodingUTF8);
NSLog(#"escapedString: %#",escapedString);
#try
{
NSString *post =[[NSString alloc] initWithFormat:#"gid=%#&image=%#",gameid,escapedString];
NSLog(#"%#",post);
NSURL *url=[NSURL URLWithString:#"http://mywebspace/updategameimage.php"];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:url];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setValue:#"application/json" forHTTPHeaderField:#"Accept"];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:postData];
NSError *error = [[NSError alloc] init];
NSHTTPURLResponse *response = nil;
NSData *urlData=[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
NSLog(#"Response code: %d", [response statusCode]);
if ([response statusCode] >=200 && [response statusCode] <300) {
NSString *responseData = [[NSString alloc]initWithData:urlData encoding:NSUTF8StringEncoding];
NSLog(#"Response ==> %#", responseData);
SBJsonParser *jsonParser = [SBJsonParser new];
NSDictionary *jsonData = (NSDictionary *) [jsonParser objectWithString:responseData error:nil];
NSLog(#"%#",jsonData);
NSInteger type = [(NSNumber *)[jsonData objectForKey:#"type"] integerValue];
NSLog(#"%d",type);
if (type==1) {
[self alertStatus:#"You can Keep on Drawing" :#"Sketch Updated"];
}
}
}
#catch (NSException * e) {
NSLog(#"Exception: %#", e);
[self alertStatus:#"Unable to connect with game." :#"Connection Failed!"];
}
}
[av dismissWithClickedButtonIndex:0 animated:YES];
[av release]; av=nil;
}
UI updates are done on main thread. You have started activity indicator on main thread.It's fine.
Now, you are making synchronous network call on main thread. It should be asynchronous. Here until you will receive the response from network call, your main thread will remain busy and your UI will not be updated.
To update the UI, you can either make the network call asynchronous or you can start the activity indicator in a separate function and then delay the call of network activity by performselector:afterdelay method.
You can use GCD, Raywenderlich Tutorial
-(IBAction)update:(id)sender
{
/*
Setup indicator and show it
*/
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0), ^{
/*
Do network call
*/
dispatch_async(dispatch_get_main_queue(), ^{
/*
Update UI
*/
});
});
}

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