iOS – Animation glitch with UIToolbar - objective-c

Question

I'm getting a "weird" animation glitch when I add a UIToolbar to the view. I'm animating the UIToolbar so it slides up from the bottom together with either a UIPickerView or a UIDatePicker. At first I see it's sliding up but after the animation is finished it quickly disappears. This happens when I slide down (animating the UIPickerView to slide down off the screen) and right after that I have another UIPickerView slide up.
I noticed that if I set a delay (- performSelector...) on the slide up call for 0.3 seconds it will display the UIToolbar properly (anything less than 0.3 seconds will still have the same glitch). What might be causing this?
EDIT: Perhaps I should place both the UIToolbar and UIDatePicker in a new UIView container?
This is the code I'm using:
if ([self.view.subviews containsObject:self.dateRepeatPicker]) {
[self dismissDateRepeatPickerSegmentChanged:NO];
// "Hack", if I don't delay this call the UIToolbar will not display
[self performSelector:#selector(showDatePicker) withObject:nil afterDelay:0.3];
} else if (![self.view.subviews containsObject:self.datePicker]) {
[self showDatePicker];
}
- (void)dismissDateRepeatPickerSegmentChanged:(BOOL)segmentChanged {
CGRect toolbarTargetFrame = CGRectMake(0, self.view.bounds.size.height, 320, 44);
CGRect dateRepeatPickerTargetFrame = CGRectMake(0, self.view.bounds.size.height+44, 320, 216);
[UIView animateWithDuration:0.2
animations:^{
self.pickerToolbar.frame = toolbarTargetFrame;
self.dateRepeatPicker.frame = dateRepeatPickerTargetFrame;
}
completion:^(BOOL finished) {
if (segmentChanged) {
[self.pickerToolbar removeFromSuperview];
[self.dateRepeatPicker removeFromSuperview];
[self.remindMeTableView reloadData];
} else {
[self.pickerToolbar removeFromSuperview];
[self.dateRepeatPicker removeFromSuperview];
}
}];
}
- (void)showDatePicker {
// Create the Toolbar over the Picker
CGRect toolbarTargetFrame = CGRectMake(0, self.view.bounds.size.height-216-44, 320, 44);
if (self.pickerToolbar == nil) {
self.pickerToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, self.view.bounds.size.height, 320, 44)];
self.pickerToolbar.barStyle = UIBarStyleBlack;
self.pickerToolbar.translucent = YES;
}
UIBarButtonItem *spacer = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:#"picker-dismiss.png"] style:UIBarButtonItemStyleBordered target:self action:#selector(dismissDatePickerToolbar)];
[self.pickerToolbar setItems:[NSArray arrayWithObjects:spacer, doneButton, nil]];
[self.view addSubview:self.pickerToolbar];
// Create the Picker under the Toolbar
CGRect datePickerTargetFrame = CGRectMake(0, self.view.bounds.size.height-216, 320, 216);
if (self.datePicker == nil) {
self.datePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, self.view.bounds.size.height+44, 320, 216)];
[self.datePicker setMinuteInterval:5];
[self.datePicker addTarget:self action:#selector(changeDate:) forControlEvents:UIControlEventValueChanged];
}
[self.view addSubview:self.datePicker];
[UIView animateWithDuration:0.2 animations:^{
self.pickerToolbar.frame = toolbarTargetFrame;
self.datePicker.frame = datePickerTargetFrame;
}];
}

Answer 1

Solved by adding the UIPickerView and the UIToolbar to a containing UIView and then animating the containing UIView.