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General Discussion

Posted by NAUSHAD DARUWALLA
NAUSHAD DARUWALLA
1,587 Points

How to use pickerView

I am trying to use a picker view with three components in it and I have all the code in, but when i run it in the simulator the pickerView shows up blank. I've attached the pickerView to the .h file and then I have put in the delegate and dataSource methods (the following) -(void) viewWillAppear:(BOOL)animated { self.activityTypeArray = [[NSArray alloc] initWithObjects:@"Homework",@"Study", nil];

self.activityTypeActivityArray = [[NSArray alloc] initWithObjects:@"Quiz",@"Test", nil];

hierarchyTableViewController* classSourceArray = [[hierarchyTableViewController alloc] init];

self.classArray = [[NSArray alloc] initWithArray:classSourceArray.classHierarchyArray];

}

  • (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView { return 3; }

  • (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {

    if (component == 0) {

    return [self.activityTypeArray count];

    } else if (component == 1) { return [self.classArray count]; } else { return [self.activityTypeActivityArray count]; }

}

  • (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {

    if (component == 0) { return [self.activityTypeArray objectAtIndex:row]; } else if (component == 1) {

    return [self.classArray objectAtIndex:row];

    } else { return [self.activityTypeActivityArray objectAtIndex:row]; }

}

Why is it not showing up in the simulator?