Implementing UIDatePicker and UIPickerView with a UIButton - ios

Question

I'm implementing a user form in an iOS app that uses both a UIPickerView and UIDatePicker as input devices from a user. I've implemented each of these as a view external to the main UIViewController in the scene and have them showing and hiding using autolayout by adding and removing constraints.
Here's my problem: I'm maintaining separate constraints and hide/show methods for animating each of these views in and out. It's a lot of repeat code and I get the sense that there has to be a cleaner way to do this, since it seems to be a very common design pattern in iOS apps. I'm fairly new at this, so I feel like I'm missing something.
Is there a better design pattern than this for using multiple input devices to UIButtons??
Here's a sampling of the code i'm using to maintain this...
var datePickerViewBottomConstraint: NSLayoutConstraint!
var datePickerViewTopConstraint: NSLayoutConstraint!
var storagePickerViewBottomConstraint: NSLayoutConstraint!
var storagePickerViewTopConstraint: NSLayoutConstraint!
#IBAction func storageButtonClicked(sender: UITextField) {
storagePickerView.translatesAutoresizingMaskIntoConstraints = false
storagePickerViewBottomConstraint = storagePickerView.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor)
UIView.animateWithDuration(0.4, animations: {
self.storagePickerViewTopConstraint.active = false
self.storagePickerViewBottomConstraint.active = true
self.view.layoutIfNeeded()
})
}
#IBAction func datePumpedClicked(sender: UIButton) {
datePickerView.translatesAutoresizingMaskIntoConstraints = false
datePickerViewBottomConstraint = datePickerView.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor)
UIView.animateWithDuration(0.4, animations: {
self.datePickerViewTopConstraint.active = false
self.datePickerViewBottomConstraint.active = true
self.view.layoutIfNeeded()
})
}
#IBAction func datePickerDismiss(sender: AnyObject) {
datePumpedLabel.setTitle(Global.dateFormatter.stringFromDate(datePicker.date), forState: UIControlState.Normal)
datePickerView.translatesAutoresizingMaskIntoConstraints = false
datePickerViewTopConstraint = datePickerView.topAnchor.constraintEqualToAnchor(view.bottomAnchor)
UIView.animateWithDuration(0.4, animations: {
self.datePickerViewBottomConstraint.active = false
self.datePickerViewTopConstraint.active = true
self.view.layoutIfNeeded()
})
}
#IBAction func storagePickerDismiss(sender: AnyObject) {
storagePickerView.translatesAutoresizingMaskIntoConstraints = false
storagePickerViewTopConstraint = storagePickerView.topAnchor.constraintEqualToAnchor(view.bottomAnchor)
UIView.animateWithDuration(0.4, animations: {
self.storagePickerViewBottomConstraint.active = false
self.storagePickerViewTopConstraint.active = true
self.view.layoutIfNeeded()
})
}
Here's a screenshot of my storyboard...
Storyboard

Answer 1

You guys, I figured out a better way!
The thing that I was missing originally is that when you remove views from the superview, all the constraints are deleted. This makes things a lot easier.
I kept 1 constraint class variable for the view that is currently being shown, so the view can animate down out of place.
I also added a "setup" function to get the view in place on viewdidload(). Without this the view will always animate in from the top the first time it appears (couldn't figure out a way around this).
Here's what I used:
var secondaryMenuBottomConstraint: NSLayoutConstraint!
func setupSecondaryMenu(secondaryMenu: UIView){
secondaryMenu.translatesAutoresizingMaskIntoConstraints = false
let topConstraint = secondaryMenu.topAnchor.constraintEqualToAnchor(view.bottomAnchor)
let leftConstraint = secondaryMenu.leftAnchor.constraintEqualToAnchor(view.leftAnchor)
let rightConstraint = secondaryMenu.rightAnchor.constraintEqualToAnchor(view.rightAnchor)
view.addSubview(secondaryMenu)
NSLayoutConstraint.activateConstraints([topConstraint, leftConstraint, rightConstraint])
self.view.layoutIfNeeded()
secondaryMenu.removeFromSuperview()
}
func showSecondaryMenu(secondaryMenu: UIView){
//Close any open keyboards
amountTextField.resignFirstResponder()
notesTextField.resignFirstResponder()
//Add the view and then add constraints to show the submenu below the current view
secondaryMenu.translatesAutoresizingMaskIntoConstraints = false
let topConstraint = secondaryMenu.topAnchor.constraintEqualToAnchor(view.bottomAnchor)
let leftConstraint = secondaryMenu.leftAnchor.constraintEqualToAnchor(view.leftAnchor)
let rightConstraint = secondaryMenu.rightAnchor.constraintEqualToAnchor(view.rightAnchor)
view.addSubview(secondaryMenu)
NSLayoutConstraint.activateConstraints([topConstraint, leftConstraint, rightConstraint])
secondaryMenuBottomConstraint = secondaryMenu.bottomAnchor.constraintEqualToAnchor(view.bottomAnchor)
//animate the view up into place
UIView.animateWithDuration(0.4, animations: {
topConstraint.active = false
self.secondaryMenuBottomConstraint.active = true
self.view.layoutIfNeeded()
})
}
func dismissSecondaryMenu(secondaryMenu: UIView){
if secondaryMenu.superview != nil {
secondaryMenu.translatesAutoresizingMaskIntoConstraints = false
let secondaryMenuTopConstraint = secondaryMenu.topAnchor.constraintEqualToAnchor(view.bottomAnchor)
self.secondaryMenuBottomConstraint.active = false
UIView.animateWithDuration(0.4, animations: {
secondaryMenuTopConstraint.active = true
self.view.layoutIfNeeded()
}, completion: {(finished:Bool) in
secondaryMenu.removeFromSuperview()
})
}
}