Question

I am working on a view that selects an image (chart) based on user input through a dependent picker which uses a plist file that contains three arrays containing about 40 strings each.

About 50% of the time when I run the app, it just shuts down immediately, but the other times that it does run, it will work fine until I start scrolling through the picker at which point it crashes after about 4 seconds. It also wont show one of the array names on the left component.

I tried running the app with the analyzer to check on a memory leak, but it wont run at all if I am using analyzer in memory leak mode. The code is almost straight out of a book.

Here is the relevant code:

    -(void) viewDidLoad {
        [super viewDidLoad];
        UIImageView *tempImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"US High Index.jpg"]];
        self.imageView = tempImageView;
        NSString *string = @"US High Index";
        self.chartNameLabel.text = string;
        [string release];
        [tempImageView release];


    scrollView.contentSize = CGSizeMake(imageView.frame.size.width , imageView.frame.size.height);
    scrollView.maximumZoomScale = 4.0;
    scrollView.minimumZoomScale = .05;
    scrollView.clipsToBounds = YES;
    scrollView.delegate = self;

    [scrollView addSubview:imageView];

    NSBundle *bundle = [NSBundle mainBundle];
    NSString *plistPath = [bundle pathForResource:@"ChartTypes" ofType:@"plist"];

    NSDictionary *dictionary = [[NSDictionary alloc]initWithContentsOfFile:plistPath];

    self.chartsDictionary   = dictionary;


    NSArray *components = [self.chartsDictionary allKeys];
    self.chartTypes = components;


    NSString *selectedChartType = [self.chartTypes objectAtIndex:0];
    NSArray *array = [chartsDictionary objectForKey:selectedChartType];
    self.charts = array;

    [dictionary release];
    [array release];

    [selectedChartType release];
    [plistPath release];
    [bundle release];
}



-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
    return 2;
}

    -(NSInteger)pickerView:(UIPickerView *)pickerView
    numberOfRowsInComponent:(NSInteger)component {
        if (component == kChartTypeComponent ) 
            return [self.chartTypes count];

            return [self.charts count];

    }

    #pragma mark Picker delegate methods
    -(NSString *)pickerView:(UIPickerView *)pickerView
    titleForRow:(NSInteger)row
               forComponent:(NSInteger)component {
        if (component == kChartTypeComponent ) 
            return [self.chartTypes objectAtIndex:row];

            return [self.charts objectAtIndex:row];



    }

    -(void)pickerView:(UIPickerView *)pickerView
          didSelectRow: (NSInteger)row
          inComponent:(NSInteger)component {
        if (component == kChartTypeComponent ) {
            NSString *selectedChartType = [self.chartTypes objectAtIndex:row];
            NSArray *array = [chartsDictionary objectForKey:selectedChartType];
            self.charts = array;
            [picker selectRow: 0 inComponent:kChartComponent animated: YES];
            [picker reloadComponent:kChartComponent];

        }
        }

Answer 1

I think you don’t have to call

[array release];
[selectedChartType release];

in your viewDidLoad method, because both objects are autoreleased. Maybe that could cause the crash.