UIPickerView doesn't "snap" to rows and moves out of bounds - ios

Question

I have a problem with UIPickerView. Following a tutorial on YT I created a UIPickerView in a popover after tapping on a textfield.
Everything looks fine, but the UIPickerView acts kind of strange. If I just tap on a row i want to select, it rolls up/down normally to this specific row and makes a selection. But if I try to scroll with my finger it doesn't roll as smooth as it should with a momentum and it doesn't snap on any of the rows. It also doesn't make a selection, but it makes a sound like it does. Worst of all, the picker doesn't seem to care about the number of rows and I can roll up and down as far as I want, although there are no selectable rows anymore.
Here is my code.
decayStatesArray contains four simple String-objects. The UITextfield und the activeDecayString are used in the "donePressed"-methode.
The main function:
-(void)showPicker:(UITextField *)textField {
activeTextfield = textField;
//for the default sizes of a UIPickerView
decayStatePicker = [[UIPickerView alloc] init];
UIViewController *popOverContent = [[UIViewController alloc] init];
UIView *popOverView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [decayStatePicker frame].size.width, [decayStatePicker frame].size.height+44)];
decayStatePicker = [[UIPickerView alloc] initWithFrame:CGRectMake([popOverView frame].origin.x, [popOverView frame].origin.y + 44, 0, 0)];
pickerToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake([popOverView frame].origin.x, [popOverView frame].origin.y, [popOverView frame].size.width, 44)];
[decayStatePicker setDataSource:self];
[decayStatePicker setDelegate:self];
[decayStatePicker setShowsSelectionIndicator:YES];
[decayStatePicker selectRow:0 inComponent:0 animated:YES];
//Create Toolbar
[pickerToolbar setBarStyle:UIBarStyleBlackTranslucent];
UIBarButtonItem *flexibleSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:#"Done" style:UIBarButtonItemStyleBordered target:self action:#selector(donePressed)];
UIBarButtonItem *cancelButton = [[UIBarButtonItem alloc] initWithTitle:#"Cancel" style:UIBarButtonItemStyleBordered target:self action:#selector(cancelPressed)];
[pickerToolbar setItems:[NSArray arrayWithObjects:flexibleSpace, doneButton, cancelButton, nil]];
[popOverView addSubview:decayStatePicker];
[popOverView addSubview:pickerToolbar];
[popOverContent setView:popOverView];
pickerPopoverController = [[UIPopoverController alloc] initWithContentViewController:popOverContent];
pickerPopoverController.popoverContentSize = CGSizeMake([popOverView frame].size.width, [popOverView frame].size.height);
[pickerPopoverController presentPopoverFromRect:[textField frame] inView:[self view] permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}
The delegate methodes:
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
return 1;
}
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent: (NSInteger)component {
return [decayStatesArray count];
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [decayStatesArray objectAtIndex:row];
}
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
if ([pickerView isEqual:decayStatePicker]) {
NSLog(#"The Picker is: %#", pickerView);
NSLog(#"The item is: %#", [decayStatesArray objectAtIndex:row]);
}
activeDecayString = [decayStatesArray objectAtIndex:row];
}