How to pass a UIButton's frame and origin between ViewControllers - ios

Question

I want to do an animation that zooms in from a calendar, specifically with the origin and frame size being that of the button that represent's today's date. Here is the code for determining the todayButton inside CalendarMonthView.m:
NSDate *date = (weekdayOffset > 0) ? [_monthStartDate dateByAddingTimeInterval:-1 * weekdayOffset * D_DAY] : _monthStartDate;
BOOL bEnabled = (weekdayOffset == 0);
CGRect buttonFrame = CGRectMake (0, 0, 81, 61);
int idx = -1 * weekdayOffset;
for (int y = 0; y < 6; y++) {
buttonFrame.origin.x = 0;
for (int x = 0; x < 7; x++) {
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.tag = idx++;
[button setFrame:buttonFrame];
[button setBackgroundImage:[UIImage imageNamed:#"calendarFlyout_dayContainer_today.png"] forState:UIControlStateSelected];
[button setBackgroundImage:[UIImage imageNamed:#"calendarFlyout_selected.png"] forState:UIControlStateHighlighted];
button.titleLabel.font = [UIFont fontWithName:#"TitilliumWeb-Regular" size:18.0];
button.titleLabel.textAlignment = NSTextAlignmentCenter;
// TODO: optimize performance
int dayOfMonth = (int)[_calendar component:NSCalendarUnitDay fromDate:date];
if (dayOfMonth < prevDayOfMonth) {
bEnabled = !bEnabled;
}
prevDayOfMonth = dayOfMonth;
[button setTitle:[NSString stringWithFormat:#"%d", dayOfMonth] forState:UIControlStateNormal];
[button setTitleColor:[UIColor darkGrayColor] forState:UIControlStateNormal];
[button setTitleColor:[UIColor lightGrayColor] forState:UIControlStateDisabled];
[button setTitleColor:[UIColor whiteColor] forState:UIControlStateHighlighted];
[button setTitleColor:[UIColor whiteColor] forState:UIControlStateSelected];
[button setBackgroundImage:[UIImage imageNamed:((bEnabled) ? #"calendarFlyout_dayContainer_insideMonth.png"
: #"calendarFlyout_dayContainer_outsideMonth.png")]
forState:UIControlStateNormal];
// button.enabled = bEnabled;
button.selected = [date isToday];
if (button.selected == NO) {
button.highlighted = (_currentDayDate) ? [date isEqualToDateIgnoringTime:_currentDayDate] : NO;
} else {
// Set buttonHolder to today
}
[button addTarget:self action:#selector (dayButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
[_dayButtonsHolderView addSubview:button];
buttonFrame.origin.x += buttonFrame.size.width;
date = [date dateByAddingTimeInterval:D_DAY];
}
buttonFrame.origin.y += buttonFrame.size.height;
}
- (IBAction)dayButtonTapped:(id)sender
{
if (_delegate) {
UIButton *button = (UIButton *)sender;
NSDate *selectedDate = [_monthStartDate dateByAddingDays:button.tag];
[_delegate performSelector:#selector (calendarMonthView:dateSelected:) withObject:self withObject:selectedDate];
}
}
I want to get the frame of button and use it in this animation used in CalendarFlyoutView.m.
I'm new to iOS programming and I read up on some delegate information and passing information through segues, but it doesn't seem to help me here.
Any help would be greatly appreciated.

Answer 1

Use the transform feature.
// animate in year calendar
_yearCalendarView.hidden = NO;
self.curMonthView.monthLabel.hidden = YES;
CalendarMonthView *monthView = [CalendarMonthView new];
monthView.delegate = self;
CGRect buttonFrame = _currentDayButtonFrame;
_yearCalendarView.frame = CGRectMake(buttonFrame.origin.x, buttonFrame.origin.y + buttonFrame.size.height, buttonFrame.size.width, buttonFrame.size.height);
NSLog(#"_yearCalendarView frame: %#", NSStringFromCGRect(_yearCalendarView.frame));
_yearCalendarView.transform = CGAffineTransformMakeScale(0.01, 0.01);
[UIView animateWithDuration:kAnimation_ExpandCalendarDuration delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
_yearCalendarView.transform = CGAffineTransformIdentity;
_yearCalendarView.frame = CGRectMake(_monthSwiperScrollView.frame.origin.x, _monthBarImageView.frame.size.height + 20, _monthSwiperScrollView.frame.size.width + 2, _yearFlyoutHeight);
} completion:^(BOOL finished) {
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector:#selector (yearCalendarAnimationDidStop:finished:context:)];
}];

Answer 2

If you are making a segue from the CalendarMonthView to the CalendarFlyoutView then you can just add this method to the CalendarMonthView.
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
CalendarFlyoutView * view = segue.destinationViewController;
view.buttonFrame = button.frame;
}
and in your CalendarFlyoutView.h
#interface CalendarFlyoutView : UIViewController
#property CGRect buttonFrame;
#end

Answer 3

A couple of questions that need to be answered to best help you:
1) Are CalendarMonthView and CalendarFlyoutView UIView or UIViewController? You say view controller, but the class name says otherwise.
2) What is happening in the method 'dayButtonTapped'? Are you performing a segue there? Are you somehow creating or loading an instance of CalendarFlyoutView?
3) If you are not using a segue, are you somehow creating and add a child view controller for CalendarFlyoutView to CalendarMonthView?
4) What is the desired transition (your animation)? Does the CalendarFlyoutView start at the same size as the button, then fill the whole screen?
5) Is there a specific reason that you are setting the button's frame instead of constraining it in the correct place?
Once we know a little more about these questions we should be able to provide some more concrete suggestions.

Answer 4

It's still not very clear where the actual animation code is being run. In your question, you state "I want to get the frame of button and use it in this animation used in CalendarFlyoutView.m." which seems to imply the animation code is in CalendarFlyoutView, which seems like an odd place for it.
There are a few things I could recommend, given my incomplete understanding of the whole of the code:
1) Move the animation code to the dayButtonTapped method, where you already have a reference to the button, and therefore it's frame. It also seems like a more logical place for it.
2) Where ever you are instantiating the CalendarFlyoutView (not shown in the code you posted), assign the button frame there.
3) If there is only a single instance of CalendarFlyoutView and you have a reference to it in CalendarMonthView, you could assign a property of the flyout view that is the frame of the button you already have a reference to in the dayButtonTapped method.
I have to add though, that these are just work arounds to what seems like a structural issue. Is this a reusable control you are trying to write? Why did you decide to not use the storyboard or view controllers? Why are you using frames and absolute sizes and positions at all instead of letting auto layout do it's job (you will bang your head against the wall for hours trying to tweak everything to run correctly in all orientations and all possible device screen sizes).