Right part of UIScrollView doesn't work in Landscape mode - iphone

Using the Interface Builder, I created a view with a UIScrollView in it.
I programmaticly add the buttons to the empty UIScrollView.
When the orientation changes, I use
- (void) willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
to call a method that resets the buttons on screen.
After that, the uiScrollView-content gets a new size using setContentSize.
No matter the width of the ContentSize, I can only interact (scroll/or tap a button) on the first 320px of the screen - which is the screen width in portrait mode.
When I set the contentSize-width to 2000, I can scroll to the left, but only with my fingers on the first 320 px instead of the full 480 (using a 3.5 inch iPhone).
What am I missing?

You need to resize the scrollview's frame, not just the content size (in fact, often you don't need to resize the content size, as the content may not change following an orientation change, but just the frame).

I had the same problem with a Popup (UIView) that was called from a (UIViewController).
In the UIViewController the popup was created as followed
func createPopup() {
let myPopup = MyPopup(frame: UIScreen.mainScreen().bounds)
self.view.addSubview(myPopup)
}
In the Popup (UIView) I needed to override layoutSubviews as follows:
override func layoutSubviews() {
super.layoutSubviews()
self.setNeedsDisplay()
let mainScreenBounds = UIScreen.mainScreen().bounds
view.frame = mainScreenBounds
super.frame = mainScreenBounds <-- Need to update the parent
** perform additional rotation/orientation code here **
}

Related

UIButton action is not triggered after constraint layouts changed

I have got an UIButton on a storyboard ViewController. When I load data into the form and the layout is significantly changing the button does not recognise the touch action.
I have figured out that when button is visible on the scrollview right after it if filled with data, the touch action works.
If the data too long and the button is not visible at first, just when it is scrolled into the display, the touch action does not work.
I was checking if something is above the button, but nothing. I have tried to change the zPosition of the button, not solved the problem.
What can be the issue?
I have made custom classes from the UIScrollView and the UIButton to check how the touches event triggered. It is showing the same behaviour, which is obvious. If the button is visible right at the beginning, the UIButton's touchesBegan event is triggered. If the button moves down and not visible at the beginning, it is never triggered, but the scrollview's touchesBegan is called instead.
Depending on the size of the data I load into the page sometimes the button is visible at the beginning, but the form can be still scrolled a bit. In this case the button still work, so it seems that this behaviour is not depending on if the scrollview is scrolled before or not, just on the initial visibility of the button.
Is there any layout or display refresh function which should be called to set back the behaviour to the button?
The code portion which ensures that the contentview is resized for the scroll if the filled data requires bigger space.
func fillFormWithData() {
dispDescription.text = jSonData[0]["advdescription"]
dispLongDescription.text = jSonData[0]["advlongdesc"]
priceandcurrency.text = jSonData[0]["advprice"]! + " " + jSonData[0]["advpricecur"]!
validitydate.text = jSonData[0]["advdate"]!
contentview.layoutIfNeeded()
let contentRect = CGRect(x: 0, y: 0, width: scrollview.frame.width, height: uzenetbutton.frame.origin.y+uzenetbutton.frame.height+50)
contentview.frame.size.height = contentRect.size.height
scrollview.contentSize = contentview.bounds.size
}
Ok, so another update. I have coloured the contentview background to blue and the scrollview background to white. When I load the data and resize the layout constraints, the contentview is resizing as expected, however now the scrollview is going to the bottom. After I scroll the view it is resizing to the original size which fits the screen. Now the button is only recognised when I touch the are which is blue behind. With the white background it is not recognised anymore, so it seems that the scrollview is hiding the button.
Let me get this clear the button is added in storyboard and it is a spritekit project?? If you are using zPosition?? Why don’t u connect the UIButton via the assistant editor as an IBAction then the action is always tied to the button.
You can also do it differently
Create an SKLabelNode and put it on the screen where you want to have the button and then set a name to it as myButton
override func touchesBegan(_ touches: Set<UITouch>, with event:
UIEvent?) {
if let touch = touches.first {
let location = touch.location(in: self)
let tappedNodes = nodes(at: location)
for node in tappedNodes {
if node.name == "myButton" {
// call your action here
}
}
}
}
EDIT 1:
You could also try auto resizing your scrollView.content this works also if you are adding any views via the app or programmatically
private func resizeScrollView(){
print("RESIZING THE SCROLLVIEW from \(scrollView.contentSize)")
for view in scrollView.subviews {
contentRect = contentRect.union(view.frame)
}
scrollView.contentSize = CGSize(width: contentRect.size.width, height: contentRect.size.height + 150)
print("THE CONTENT SIZE AFTER RESIZING IS: \(scrollView.contentSize)")
}
EDIT 2: I think I found the issue with your project. You need to move the MessageButton(UzenetButton) above DispDescription label in the object inspector in that way it will always be above your message textView.
At the moment the UzeneButton is at the very far back in your view hierarchy so if your textView is resizing whilst editing it covers the button that is why you cannot click on it.
See #Endre Olah,
To make situation more clear do one more thing, set clipToBound property of contentview to true.
you will notice that after loading of data your button not fully visible, it means it is shifting out of bound of its parentView (ContentView)
And that's why button is not taking your touch. However, if you carefully touch upper part of button it still do its job. Because upper part is still in bound of ContentView
Solution :
After loading of data you have to make sure that you increase height of ContentView such that button should never go out of bound of its parentView(ContentView).
FOR EXAMPLE
#IBOutlet var heightConstraintOfContentView : NSLayoutConstraint!
After loading of data
let contentRect = CGRect(x: 0, y: 0, width: scrollview.frame.width, height: uzenetbutton.frame.origin.y+uzenetbutton.frame.height+50)
heightConstraintOfContentView.constant = contentRect.size.height
contentView.layoutIfNeeded()
I use following steps when I need to use scrollview with dynamic content:
1) Firstly add a scrollView with top, bottom, trailing and leading is 0 to super view.
2) Add a view to scrollView and view's trailing, leading bottom and top space to scrollView can be set to 0 (or you can add margin optionally).
3) Now, you should add UI elements like buttons, labels with appropriate top, bottom, trailing and leading margins to each other.
4) Lastly, add equal height and equal width constraint to view with Safe Area:
and change equal height priority of view to 250:
It should solve your problem with UIScrollView.
Finally, I have found the solution in another chain, once it became clear that the scrollview's contentview is resizing on scroll event to the original size. (Not clear why this is like this, but that is the fact.)
So I had to add a height constraint to the contentview in the storyboard and create an outlet to it and adjust this constraint when the content size is changing, like this:
#IBOutlet weak var ContentViewHeight: NSLayoutConstraint!
func fillFormWithData() {
dispDescription.text = jSonData[0]["advdescription"]
dispLongDescription.text = jSonData[0]["advlongdesc"]
priceandcurrency.text = jSonData[0]["advprice"]! + " " + jSonData[0]["advpricecur"]!
validitydate.text = jSonData[0]["advdate"]!
contentview.layoutIfNeeded()
let contentRect = CGRect(x: 0, y: 0, width: scrollview.frame.width, height: uzenetbutton.frame.origin.y+uzenetbutton.frame.height+50)
contentview.bounds = contentRect
scrollview.contentSize = contentRect.size
----------- This is the key line to the success ----------
ContentViewHeight.constant = contentRect.size.height
----------------------------------------------------------
}
After this is added, it works perfectly.

My ScrollView is not scrolling vertically

I'm writing an app in Xcode 9 with Swift 4 and I've added a UIScrollview to a view which is intended to show a jPeg which is 3030 pixels in height. I've added the scrollview to my view and assigned the delegate in Outlets in IB. I've attached the IBOutlet called scrollView to the UIScrollview and added a UIImageView with the jPeg to the UIScrollview. I've set the size of the UIScrollView to 375W and 620H and then set the UIImageView to 375W and 3030H. this should complete the work in Interface builder.
In the Controller I've added UIScrollViewDelegate to the Class and added the code below to ViewDidLoad
//scrollView.delegate = self
scrollView.contentSize = CGSize(width: 375, height: 3040)
I've commented out the delegate line as I've done that in IB. When I run the app, the screen comes upon with the image but when I try to scroll it barely scrolls more than one screen. What have I missed?
You need to add a UIView inside your scrollview and then add that view top/bottom/leading/trailing 0 to scrollview then add your image view inside view and add image view bottom constraint to that view, So your scroll view will work properly.
Please refer below image for more details.
You have to place your scroll view inside a UIView and another UIView inside your scroll view.
Outer view Constraints: Leading,trailing,top and bottom - 0
Scroll view Constraints: Leading,trailing,top and bottom - 0
Inner view Constraints: Leading,trailling and top to Superview, Equal width to Outer view , Bottom space to -250 and Height equals 900(Height of your content)
Set your contentsize now.
You can implement as below image screen shots
//Height Constant of image
#IBOutlet weak var ConstHeight: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
if #available(iOS 11.0, *) {
self.scrollView.contentInsetAdjustmentBehavior = .never
}else{
self.automaticallyAdjustsScrollViewInsets = false
}
//You can change height on here too
self.ConstHeight.constant = 800
}

Scroll in UIScrollView with tvOS

I stuck with scrolling content inside UIScrollView in my tvOS app.
I have scrollView with height = 400 and width = 400. Inside this scrollview I have non-scrollable UITextView with height = 800 and width = 400. So I want to scroll this text.
But my scroll view is not scrolled, I don't see any scrolling indicators and also my scrollView have isFocused value = false. How can I solve this problem?
p.s. update I created separate ViewController (image below).
It have black ScrollView and white view with big height with label in the middle of it. ScrollView has fixed width and height and there is no scrolling for some reason! I even didn't connect any separate class - just created it from Interface builder.
UIView isn't focusable by default (and as such in tvOS it can't be scrolled) . You have to subclass it to override canBecomeFocused:
class myUIView: UIView {
override var canBecomeFocused: Bool {
return true
}
}
Then in your example use the class myUIView instead of UIView for your long white view. Setting the right constraints you wouldn't need to design the views out of the controller view boundaries in IB either. Check this answer with the linked gist to see how to build the constraints.
I think you can use the
func gestureRecognizer (_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool
method to judge the view and scroll it
According to the view you touch to do something to intercept
There is some way to fix your problem.
Please check your scrollview in storyboard, is your scrolling or vertical indicator is checked?
U can make your textview scrollable if u just want to scroll the textview content
There is problem in your constraint, you need to cleary add the height, vertical space top, vertical space bottom from your textview to your scrollview.
Hope these advice can help you
So you have to set the scrollview's content size larger than the scrollview bounds, so you should set contentsize to (400, 800), probaly in you xib

Swift iOS -How to Add Subview to Window's Center?

I have an activity indicator that gets presented on an iPhone and iPad. In the iPad in split screen mode it gets presented to whichever side of the view that called it. I would instead like it to get presented in the middle/center the window's screen. If I do it this way wether on the iPhone in portrait or iPad in split screen mode it will always be in the center of the screen.
How do I do this?
MyView: UIViewController{
let actInd = UIActivityIndicatorView(activityIndicatorStyle: .whiteLarge)
#IBAction fileprivate func buttonPressed(_ sender: UIButton) {
guard let window = UIApplication.shared.keyWindow else { return }
//how to add actInd as subview to the window' screen?
actInd.startAnimating()
}
}
It's pretty simple. Turn off the auto-resizing mask. Add the add actInd to window, then set the center anchors.
actInd.translatesAutoresizingMaskIntoConstraints = false
window.addSubview(actInd)
actInd.centerXAnchor.constraint(equalTo: window.centerXAnchor).isActive = true
actInd.centerYAnchor.constraint(equalTo: window.centerYAnchor).isActive = true
Window is subclass of UIView. Just add it as it's subview like you're adding a view to another view. But remember that window is shared throughout your app, so adding it every-time will consume memory, remove it after your job is done.
If you want to center it in the window, you can use autoResizingMask or add constraints to it.

Determine width of UIView in Swift

I have an autolayouted UIView and need to know the width of it. How do I find the width the easiest way in Swift?
You can find the width of any view by
let width = yourView.bounds.width
If you have applied a width constraint to the view and you have an outlet for that constraint then you can find it by.
let width = yourWidthConstraint.constant
The right place to get the UIScreen frame data is in viewDidLayoutSubviews as it is called after the subViews have been laid out in screen also it is called after every time your device changes orientation such as your width will be different when your user goes into landscape mode.This is called after viewWillAppear:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
let viewWidth = self.myView.bounds.width
}
Inside implementation your view you can use
override func layoutSubviews() {
super.layoutSubviews()
// you can get width of view in this function
print(self.frame.size.width)
}