dealing with autoreleased objects within dispatch_sync












0















What is the best solution to avoid bad access in this kind of situations ?



__block NSString* string;
dispatch_sync(dispatch_get_main_queue(), ^{
string = [NSString stringWithString:@"I'm autoreleased!"];
});

NSLog(@"My string is: %@", string);


I changed my code to this:



NSMutableString *string = [[NSMutableString alloc] init];
dispatch_sync(dispatch_get_main_queue(), ^{
[string appendString:@"I'm autoreleased!"];
});

NSLog(@"My string is: %@", string);
[string release];


but I was wondering if there no better solutions










share|improve this question



























    0















    What is the best solution to avoid bad access in this kind of situations ?



    __block NSString* string;
    dispatch_sync(dispatch_get_main_queue(), ^{
    string = [NSString stringWithString:@"I'm autoreleased!"];
    });

    NSLog(@"My string is: %@", string);


    I changed my code to this:



    NSMutableString *string = [[NSMutableString alloc] init];
    dispatch_sync(dispatch_get_main_queue(), ^{
    [string appendString:@"I'm autoreleased!"];
    });

    NSLog(@"My string is: %@", string);
    [string release];


    but I was wondering if there no better solutions










    share|improve this question

























      0












      0








      0








      What is the best solution to avoid bad access in this kind of situations ?



      __block NSString* string;
      dispatch_sync(dispatch_get_main_queue(), ^{
      string = [NSString stringWithString:@"I'm autoreleased!"];
      });

      NSLog(@"My string is: %@", string);


      I changed my code to this:



      NSMutableString *string = [[NSMutableString alloc] init];
      dispatch_sync(dispatch_get_main_queue(), ^{
      [string appendString:@"I'm autoreleased!"];
      });

      NSLog(@"My string is: %@", string);
      [string release];


      but I was wondering if there no better solutions










      share|improve this question














      What is the best solution to avoid bad access in this kind of situations ?



      __block NSString* string;
      dispatch_sync(dispatch_get_main_queue(), ^{
      string = [NSString stringWithString:@"I'm autoreleased!"];
      });

      NSLog(@"My string is: %@", string);


      I changed my code to this:



      NSMutableString *string = [[NSMutableString alloc] init];
      dispatch_sync(dispatch_get_main_queue(), ^{
      [string appendString:@"I'm autoreleased!"];
      });

      NSLog(@"My string is: %@", string);
      [string release];


      but I was wondering if there no better solutions







      objective-c-blocks autorelease unsafe-unretained






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 5 '18 at 14:00









      vtruantvtruant

      1038




      1038
























          1 Answer
          1






          active

          oldest

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          2














          Since you are calling release, you must be using manual reference counting. In manual reference counting, when you store something to a variable that will outlive the scope, you must retain it, and then if you will later assign something to that variable or that variable's lifetime will end, you need to release that variable first.



          So you can do this:



          __block NSString* string;
          dispatch_sync(dispatch_get_main_queue(), ^{
          string = [[NSString stringWithString:@"I'm autoreleased!"] retain];
          // or equivalently:
          // string = [[NSString alloc] initWithString:@"I'm autoreleased!"];
          });

          NSLog(@"My string is: %@", string);
          [string release];





          share|improve this answer























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            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            2














            Since you are calling release, you must be using manual reference counting. In manual reference counting, when you store something to a variable that will outlive the scope, you must retain it, and then if you will later assign something to that variable or that variable's lifetime will end, you need to release that variable first.



            So you can do this:



            __block NSString* string;
            dispatch_sync(dispatch_get_main_queue(), ^{
            string = [[NSString stringWithString:@"I'm autoreleased!"] retain];
            // or equivalently:
            // string = [[NSString alloc] initWithString:@"I'm autoreleased!"];
            });

            NSLog(@"My string is: %@", string);
            [string release];





            share|improve this answer




























              2














              Since you are calling release, you must be using manual reference counting. In manual reference counting, when you store something to a variable that will outlive the scope, you must retain it, and then if you will later assign something to that variable or that variable's lifetime will end, you need to release that variable first.



              So you can do this:



              __block NSString* string;
              dispatch_sync(dispatch_get_main_queue(), ^{
              string = [[NSString stringWithString:@"I'm autoreleased!"] retain];
              // or equivalently:
              // string = [[NSString alloc] initWithString:@"I'm autoreleased!"];
              });

              NSLog(@"My string is: %@", string);
              [string release];





              share|improve this answer


























                2












                2








                2







                Since you are calling release, you must be using manual reference counting. In manual reference counting, when you store something to a variable that will outlive the scope, you must retain it, and then if you will later assign something to that variable or that variable's lifetime will end, you need to release that variable first.



                So you can do this:



                __block NSString* string;
                dispatch_sync(dispatch_get_main_queue(), ^{
                string = [[NSString stringWithString:@"I'm autoreleased!"] retain];
                // or equivalently:
                // string = [[NSString alloc] initWithString:@"I'm autoreleased!"];
                });

                NSLog(@"My string is: %@", string);
                [string release];





                share|improve this answer













                Since you are calling release, you must be using manual reference counting. In manual reference counting, when you store something to a variable that will outlive the scope, you must retain it, and then if you will later assign something to that variable or that variable's lifetime will end, you need to release that variable first.



                So you can do this:



                __block NSString* string;
                dispatch_sync(dispatch_get_main_queue(), ^{
                string = [[NSString stringWithString:@"I'm autoreleased!"] retain];
                // or equivalently:
                // string = [[NSString alloc] initWithString:@"I'm autoreleased!"];
                });

                NSLog(@"My string is: %@", string);
                [string release];






                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Dec 31 '18 at 3:42









                newacctnewacct

                94.7k23134194




                94.7k23134194






























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