Loading nib and instantiating view with UIDatePicker take a lot of time - ios

Question

I have simple xib with two views: container view with date picker and toolbar with bar buttons. I use it as inputView and inputAccessoryView for my input fields (<UIKeyInput>). But I've faced with performance issue: I've noticed that loading nib of this xib file and instantiating a view from nib takes ~500ms (calculated with Time Profiler instruments tool). So, instead of adding date picker to xib I create it programmatically and vuela!, instantiating takes only ~30ms.
Code example pretty straightforward:
- (void)initialize
{
NSString * className = NSStringFromClass(self.class);
UINib * nib = [UINib loadCachedForKey:className];
[classNib instantiateWithOwner:self
options:nil];
_contentView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
_contentView.frame = self.bounds;
[self addSubview:_contentView];
}
where [UINib loadCachedForKey:] is my category, which implementation is as simple as method name sounds so I think posting it here is useless.
I also have a similar xib but with UIPicker and it is instantiated fast (~70ms).
Adding date picker programmatically did work for me, but the questions are
did I do something wrong or is it normal behavior ?

Answer 1

Better not to use xib file in this, use programmatically in adding date picker: Try this if it is useful for you:
- (IBAction)btnClicked:(id)sender {
UIDatePicker *datepicker=[[UIDatePicker alloc] initWithFrame:CGRectMake(0, 250, 325, 300)];
datepicker.datePickerMode = UIDatePickerModeDate;
datepicker.hidden = NO;
datepicker.date = [NSDate date];
[datepicker addTarget:self
action:#selector(LabelChange:)
forControlEvents:UIControlEventValueChanged];
[self.view addSubview:datepicker]; //this can set value of selected date to your label change according to your condition
NSDateFormatter * df = [[NSDateFormatter alloc] init];
[df setDateFormat:#"M-d-yyyy"]; // from here u can change format..
_selectedDate.text=[df stringFromDate:datepicker.date];
}
- (void)LabelChange:(id)sender{
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:#"M-d-yyyy"];
_selectedDate.text = [NSString stringWithFormat:#"%#",
[df stringFromDate:datepicker.date]];
}