Objective C implementing a UIPickerView with a “Done” button

Question

I am trying to implement a \"Done\" button in a UIPickerView Similar to the one under this link

I looked in the class reference but I couldn t find it

Thank

Answer 1

I added a UIToolbar with a UIBarButtonItem for the 'done' button in my xib with the frame set so that it's not initially visible (y value equal to the height of the parent view).

Every time the user access the picker, I changed the frame (the y value) of the UIDatePicker and the UIToolbar with an animation so that it slides up along with the picker from the bottom of the screen similar to the keyboard.

Check out my code below.

- (IBAction)showPicker
{
    if(pickerVisible == NO)
    {
        // create the picker and add it to the view
        if(self.datePicker == nil) self.datePicker = [[[UIDatePicker alloc] initWithFrame:CGRectMake(0, 460, 320, 216)] autorelease];
        [self.datePicker setMaximumDate:[NSDate date]];
        [self.datePicker setDatePickerMode:UIDatePickerModeDate];
        [self.datePicker setHidden:NO];
        [self.view addSubview:datePicker];

        // the UIToolbar is referenced 'using self.datePickerToolbar'
        [UIView beginAnimations:@"showDatepicker" context:nil];
        // animate for 0.3 secs.
        [UIView setAnimationDuration:0.3];

        CGRect datepickerToolbarFrame = self.datePickerToolbar.frame;
        datepickerToolbarFrame.origin.y -= (self.datePicker.frame.size.height + self.datePickerToolbar.frame.size.height);
        self.datePickerToolbar.frame = datepickerToolbarFrame;

        CGRect datepickerFrame = self.datePicker.frame;
        datepickerFrame.origin.y -= (self.datePicker.frame.size.height + self.datePickerToolbar.frame.size.height);
        self.datePicker.frame = datepickerFrame;

        [UIView commitAnimations];
        pickerVisible = YES;
    }
}

- (IBAction)done
{
    if(pickerVisible == YES)
    {
        [UIView beginAnimations:@"hideDatepicker" context:nil];
        [UIView setAnimationDuration:0.3];

        CGRect datepickerToolbarFrame = self.datePickerToolbar.frame;
        datepickerToolbarFrame.origin.y += (self.datePicker.frame.size.height + self.datePickerToolbar.frame.size.height);
        self.datePickerToolbar.frame = datepickerToolbarFrame;

        CGRect datepickerFrame = self.datePicker.frame;
        datepickerFrame.origin.y += (self.datePicker.frame.size.height + self.datePickerToolbar.frame.size.height);
        self.datePicker.frame = datepickerFrame;
        [UIView commitAnimations];

        // remove the picker after the animation is finished
        [self.datePicker performSelector:@selector(removeFromSuperview) withObject:nil afterDelay:0.3];
    }
}