How to use the values out of sendAsynchronousRequest?

Question

I am parsing some JSON data using Http POST request and NSURLRequest. But when I have got the values under sendAsynchronousRequest I cannot use those out side of that request. Please see the example bellow:

[NSURLConnection sendAsynchronousRequest:rq queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
     {
         NSError *parseError = nil;
         dictionary = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
         NSLog(@"Server Response (we want to see a 200 return code) %@",response);
         NSLog(@"dictionary %@",dictionary);
     }];

My query is how can I use the dictionary value where I need it? Thanks

@vadian, I want to put those values on a table View. So how can I use it inside. — User9975, Nov 15 '16 at 20:44
Put the code to populate and reload the table view inside the completion block. Think asynchronously — vadian, Nov 15 '16 at 20:46

Teja Nandamuri · Accepted Answer · 2016-11-15T20:53:44.690

2

You can do it in many ways. One way is to declare a property and use it inside the block.

As you are making an asynchrounous call, it is better to have your own custom blocks to respond to those calls.

Declare a completion block first:

 typedef void (^ ResponseBlock)(BOOL success, id response);

and declare a method that uses this block as a param:

 - (void)processMyAsynRequestWithCompletion:(ResponseBlock)completion;

and include your async call in this method:

- (void)processMyAsynRequestWithCompletion:(ResponseBlock)completion{

 [NSURLConnection sendAsynchronousRequest:rq queue:queue completionHandler:^(NSURLResponse *response, NSData *data, NSError *error)
 {
     NSError *parseError = nil;
     dictionary = [NSJSONSerialization JSONObjectWithData:data options:0 error:&parseError];
     NSLog(@"Server Response (we want to see a 200 return code) %@",response);
     NSLog(@"dictionary %@",dictionary);
     completion(YES,response); //Once the async call is finished, send the response through the completion block
 }];

}

You can call this method anywhere you want.

 [classInWhichMethodDeclared processMyAsynRequestWithCompletion:^(BOOL success, id response) {
      //you will receive the async call response here once it is finished.
         NSDictionary *dic = (NSDictionary *)response;
       //you can also use the property declared here
           _dic = (NSDictionary *)response; //Here dic must be declared strong
 }];

edited Nov 15 '16 at 20:53

answered Nov 15 '16 at 20:18

Teja Nandamuri

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In classInWhichMethodDeclared not getting the dictionary value. – User9975 Nov 19 '16 at 16:57
classInWhichMethodDeclared is where you declared the processMyAsynRequestWithCompletion method. – Teja Nandamuri Nov 19 '16 at 17:08
Teja, Your code is working perfectly. Thanks. But I want to put my values in a tableView. Not getting the values on the TableView. – User9975 Nov 21 '16 at 19:20
in the processMyAsynRequestWithCompletion, call reloadData for the tableView, and in the datasource methods use the _dic as it contains the downloaded data – Teja Nandamuri Nov 21 '16 at 19:22
Actually when I call the method on viewDidLoad its getting datas but how can I use those globally? – User9975 Nov 21 '16 at 19:31
You need to use a datamodel that takes this data and pass on to other classes – Teja Nandamuri Nov 21 '16 at 19:33

How to use the values out of sendAsynchronousRequest?

1 Answers1