Question

I am experiencing unexpected behavior when adding objects to an NSMutablearray. Basically, i want to add an object at the end of the array. All the objects in the array should be different. But what I am seeing is that all the objects in the array equal to the last one that was inserted. I have included the relevant code:

   _trafficArray = [[NSMutableArray alloc] init];


    int _index = -1;
    int _currentIndex = 0;
    int _reportCount = 0;

TrafficReport *_report = [[TrafficReport alloc] init];


    while (true) {

        if (!xmlTextReaderRead(_reader)) break;

        switch (xmlTextReaderNodeType(_reader)) {     

            case XML_READER_TYPE_ELEMENT:


                temp = (char *)xmlTextReaderConstName(_reader);

                currentTagName = [NSString  stringWithCString:temp encoding: NSUTF8StringEncoding];

                if([currentTagName isEqualToString:@"Title"])
                {

                    _index++;

                    temp = (char *)xmlTextReaderConstName(_reader);

                    currentTagName = [NSString  stringWithCString:temp encoding: NSUTF8StringEncoding];


                    xmlTextReaderRead(_reader);

                    temp = (char*)xmlTextReaderConstValue(_reader);
                    currentTagValue = [NSString stringWithCString:temp 
                                                         encoding:NSUTF8StringEncoding];


                    _report.title = currentTagValue;

                    _reportCount++;


                }
                if ([currentTagName isEqualToString:@"Description"]) {

                    temp = (char *)xmlTextReaderConstName(_reader);

                    currentTagName = [NSString  stringWithCString:temp encoding: NSUTF8StringEncoding];

                    xmlTextReaderRead(_reader);

                    temp = (char*)xmlTextReaderConstValue(_reader);
                    currentTagValue = [NSString stringWithCString:temp 
                                                         encoding:NSUTF8StringEncoding];

                    _report.description = currentTagValue;
                    _reportCount++;


                }

            if (_reportCount==2) {


                _reportCount = 0;

                NSLog(@"updated! with index = %d and title = %@\n\n", _index, _report.title);



                [_trafficArray insertObject:_report atIndex:_index];

                [_report release];

    TrafficReport *_report = [[TrafficReport alloc] init];


            }


            continue;

        default:continue;
    }


}

Answer 1

It’s an issue of scope. After you release _report, you declare a new _report object in the scope of the if statement. Even though it has the same name as the one you declared before the while loop, it refers to a different variable. Remove the declaration (TrafficReport *) before the assignment to assign a new value to your existing _report variable instead.