[ios] Add UIPickerView & a Button in Action sheet - How?

I don't really understand why the UIPickerView is going inside a UIActionSheet. This seems to be a messy and hacky solution, which can be broken in a future iOS release. (I've had things like this break in an app before, where the UIPickerView wasn't being presented on the first tap and had to be retapped - weird quirks with the UIActionSheet).

What I did is simply implement a UIPickerView and then added it as a subview to my view, and animate it moving up as though it were being presented like an action sheet.

/// Add the PickerView as a private variable
@interface EMYourClassName ()

@property (nonatomic, strong) UIPickerView *picker;
@property (nonatomic, strong) UIButton *backgroundTapButton;

@end

///
/// This is your action which will present the picker view
///
- (IBAction)showPickerView:(id)sender {

    // Uses the default UIPickerView frame.
    self.picker = [[UIPickerView alloc] initWithFrame:CGRectZero];

    // Place the Pickerview off the bottom of the screen, in the middle set the datasource delegate and indicator
    _picker.center = CGPointMake([[UIScreen mainScreen] bounds].size.width / 2.0, [[UIScreen mainScreen] bounds].size.height + _picker.frame.size.height);
    _picker.dataSource = self;
    _picker.delegate = self;
    _picker.showsSelectionIndicator = YES;

    // Create the toolbar and place it at -44, so it rests "above" the pickerview.
    // Borrowed from @Spark, thanks!
    UIToolbar *pickerDateToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, -44, 320, 44)];
    pickerDateToolbar.barStyle = UIBarStyleBlackTranslucent;
    [pickerDateToolbar sizeToFit];

    NSMutableArray *barItems = [[NSMutableArray alloc] init];

    UIBarButtonItem *flexSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];
    [barItems addObject:flexSpace];

    // The action can whatever you want, but it should dimiss the picker.
    UIBarButtonItem *doneBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(backgroundTapped:)];
    [barItems addObject:doneBtn];

    [pickerDateToolbar setItems:barItems animated:YES];
    [_picker addSubview:pickerDateToolbar];

    // If you have a UITabBarController, you should add the picker as a subview of it
    // so it appears to go over the tabbar, not under it. Otherwise you can add it to 
    // self.view
    [self.tabBarController.view addSubview:_picker];

    // Animate it moving up
    [UIView animateWithDuration:.3 animations:^{
        [_picker setCenter:CGPointMake(160, [[UIScreen mainScreen] bounds].size.height - 148)]; //148 seems to put it in place just right.
    } completion:^(BOOL finished) {
        // When done, place an invisible button on the view behind the picker, so if the
        // user "taps to dismiss" the picker, it will go away. Good user experience!
        self.backgroundTapButton = [UIButton buttonWithType:UIButtonTypeCustom];
        _backgroundTapButton.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
        [_backgroundTapButton addTarget:self action:@selector(backgroundTapped:) forControlEvents:UIControlEventTouchUpInside];
        [self.view addSubview:_backgroundTapButton];
    }];

}

// And lastly, the method to hide the picker.  You should handle the picker changing
// in a method with UIControlEventValueChanged on the pickerview.
- (void)backgroundTapped:(id)sender {

    [UIView animateWithDuration:.3 animations:^{
        _picker.center = CGPointMake(160, [[UIScreen mainScreen] bounds].size.height + _picker.frame.size.height);
    } completion:^(BOOL finished) {
        [_picker removeFromSuperview];
        self.picker = nil;
        [self.backgroundTapButton removeFromSuperview];
        self.backgroundTapButton = nil;
    }];
}