Adding IB constraints breaks UIPickerview - ObjC

Question

I have a view built with interface builder. Whenever I add a pickerview (either via IB or programmatically) on top of the existing IB view, the pickerview will not work. The elements within the pickerview won't scroll properly... the spinner wheel always bounces back to the '0 position' & nothing can be selected. Also, the wheel no longer 'clicks'... and the wheel moves in horizontally as well as vertically... but nothing can be selected.

I even tried to add the pickerview to an actionsheet... same result.

If I completely remove ALL of the constraints in the view, the pickerview works as it should.

Any ideas on what's causing this and/or how to fix?

screen shot

Here's the code:

- (void)viewDidLoad {
    [super viewDidLoad];
    self.tabBarController.tabBar.hidden = YES;
    [self.view setBackgroundColor:[UIColor clearColor]];
    
letterArray = @[@"",@"A",@"B",@"C",@"D"];
    
    UIBarButtonItem *pBtn = [[UIBarButtonItem alloc] initWithTitle:@"picker"
                                                               style:UIBarButtonItemStylePlain
                                                              target:self
                                                                action:@selector(launchPicker:)];
    self.navigationItem.rightBarButtonItem = pBtn;
}

- (void)launchPicker:(id)sender {
    self.viewForMainPicker = [[UIView alloc]initWithFrame:CGRectMake(0, 400, [[UIScreen mainScreen] bounds].size.width, 220)];
    UIToolbar *toolBar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, [[UIScreen mainScreen] bounds].size.width, 44)];
    UIPickerview *mainPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 0, [[UIScreen mainScreen] bounds].size.width, 220)];
    
    UIFont *arrowfont = [UIFont boldSystemFontOfSize:40];
    UIFont *titlefont = [UIFont boldSystemFontOfSize:28];
    UIBarButtonItem *doneBtn = [[UIBarButtonItem alloc] initWithTitle:@"→"
                                                                style:UIBarButtonItemStylePlain
                                                               target:self
                                                               action:@selector(fakeEvent)];
    UIBarButtonItem *title = [[UIBarButtonItem alloc] initWithTitle:@"Select Gender"
                                                              style:UIBarButtonItemStylePlain
                                                             target:nil
                                                             action:nil];
    UIBarButtonItem *flex = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
                                                                          target:self
                                                                          action:nil];
    [doneBtn setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                     [UIColor colorWithRed:0.933 green:0.122 blue:0.145 alpha:1.00], NSForegroundColorAttributeName,
                                     arrowfont, NSFontAttributeName, nil] forState:UIControlStateNormal];
    [title setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:
                                     [UIColor colorWithRed:0.933 green:0.122 blue:0.145 alpha:1.00], NSForegroundColorAttributeName,
                                     titlefont, NSFontAttributeName, nil] forState:UIControlStateNormal];
    NSArray *btnArray = [[NSArray alloc] initWithObjects:flex,flex,title,flex,doneBtn,nil];
    
    mainPicker.delegate = self;
    mainPicker.dataSource = self;
    
    [toolBar setItems:btnArray];
    [viewForMainPicker addSubview:mainPicker];
    [viewForMainPicker addSubview:toolBar];

    [self.view addSubview:viewForMainPicker];
}

- (void)fakeEvent {
    NSLog(@"selected");
}

- (NSInteger)numberOfComponentsInPickerView:(nonnull UIPickerView *)pickerView {
    return 1;
}

- (NSInteger)pickerView:(nonnull UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
    return letterArray.count;
}

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
    return letterArray[row];
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
    NSString *newString = [NSString stringWithFormat:@"%@", letterArray[row]];
    NSLog(@"passing: %@",newString);
}