how to resize scroll view after remove subview swift? - ios

I have subview in a scrollview and after I remove some subview from the bottom there is a blank space and the scroll view still keeps height, not resizing. How to fix this?

Scrollview's contentHeight & contentWidth is calculated from its subviews(if used auto layout). If autolayout is not used then you need to set its content size.
So whenever you are adding or removing subviews in scrollview you need to take care of its contentHeight and contentWidth.
If you're using auto layout, you need to add constraints to newly added view in such a way that scroll view can calculate its contentHeight from it.(in auto layouts you don't need to explicitly set the content height to scroll view)
If you're using frame base layout, you need to set the contentHeight explicitly to the scroll view. In frame base layout, you need to take care of scrollviews content size.
Why is there blank space in scrollview?
When a subview is removed from scrollview, its content size need to be adjusted. It means it is not able to calculate its content size.

you can use this line
self.scrollView.contentSize = CGSize(width: self.view.frame.width, height: (YOURVIEW) - (THEREMOVEDVIEW))
I recommend you that you must save the height before remove view for later you can adjust.

UIScrollView doesn't know the height of its content automatically. You must calculate the height and width for yourself like below:
scrollView.contentSize = CGSize(width: self.view.frame.size.width, height: 700)
note: change width and height as you want.
you can try this also:
let content: CGRect = scrollView.subviews.reduce(into: .zero) { rect, view in
rect = rect.union(view.frame)
}
scrollView.contentSize = content.size

Related

XCode: Scrollview not scrolling

so I have added scrollview to my screen.
However, I'm unable to scroll up and down.
My scrollview width and size are 414 and 784 respectively while my content size is scrollView.contentSize = CGSize(width: self.view.frame.size.width, height: 800)
Why can't I scroll up and down?
How do I fix this?
You can add a UIView (call it content view) inside your scrollView with top, botttom, left, right constraints to zero. And give height constraint = 800 for this view.
This should work!
Basically, you need to add some content to the scrollView. If the height of contents becomes greater than the scrollView height, the scrollView becomes scrollable.

swift: how to adjust table view's height to fit super view's height

I have a viewController into which I dragged a tableView, but when I load data in the tableView I get a scroll, what I want is to extend this tableView to its height to fill its superView. I tried to resize the tableView by setting tableView.frame.height = tableView.contentSize.height in viewDidAppear and it worked but I don't get a scroll in the superView, the tableView just got expanded and the content is down the view but I cant scroll, I tried to put this tableView inside a scrollView but still the same thing, what can I do?
yourTableview.frame = CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: self.view.frame.size.height)
Basically what you did was adjust the height of the tableView to be is the height if its content rather than the height of the screen (the content height is larger than the screen)
The table should carry the height of the screen (or any height you want) and if your content is bigger than the frame of your tableView it will automatically have the scrolling enabled.
Hope this helps!
If you want your scrollview to be scrollable, you need to indicate its contentSize by dynamically calculating the height of its nested components:
scrollView.isScrollEnabled = true
scrollView.contentSize = imageView.frame.height + tableview1.frame.height + tableview2.frame.height + netLabel.frame.height
Notice that you may also have to include your margins' height
I just needed to add the constraint of height of my table as an Outlet like this #IBOutlet weak var myConstraint: NSLayoutConstraint!, and the do myConstraint.constant = myTable.contentSize.height in viewDidAppear

Adding subview to scrollview

I'm trying to add a subview to a scrollview I have in my view controller:
let size:CGSize = self.view.bounds.size;
self.scrollview.contentSize.width = size.width
pageMenu = CAPSPageMenu(viewControllers: controllerArray, frame: CGRectMake(0.0, self.tableView.frame.origin.y + 130, size.width, size.height), pageMenuOptions: parameters)
self.scrollview.addSubview(pageMenu!.view)
It works to the extent that it adds it in the correct position and height I want it. But for some reason, right now it only expands to about 60% the width of the screen (I need it to be full screen).
Things I've tried
1) Setting it so self.view.frame.width
2) Setting it to the width of another full screen element.
3) Setting it to UIScreen.mainScreen().bounds
I checked the constraints of the scrollview in storyboard and it's configured to be full screen...so I'm not sure why this wont work.
This issue is related to the constraints that need to be set to the scroll view. I have answered a similar question here. Basically you need to specify a constraint for the scroll view's content view's width. See my answer in above link for a detailed description. The problem is that the scrollview adjusts its size to its content view's size even after we provide proper constraints to the scroll view. So we need to specify the constraints of the content view of the scroll view with respect to the scrollview and its superview so that the content in the scrollview fits our requirement.
One thing I noticed was that in your CGRectMake code you are specifying your y origin to be tableViews y value + 130. That seems like the problem to me.

Auto resize UITextView in UIScrollView

I have a question, how can I resize a textview in a scrollview and scrollview also must resize to be conformable with what size the textview will be.
Thank you.
Without auto layout it is much easier. Just get the contentSize property of the UITextView:
float textViewHeight = textView.contentSize.height;
And then set scroll view content size according to the content size of the text view:
scrollview.contentSize = CGSizeMake(320,textViewHeight + 100);
This will make the height of the scroll view the height of the content size of the textview plus 100 pixels (in case you have other stuff in your scroll view).

How to configure view width fixed width and variable height with AutoLayout

I have the following setup: a UIView containing a UILabel and a UIButton. The UIButton has fixed dimensions (it doesn't really matter). The UILabel, however, is constrained by the view's bounds.
I want to be able to set the UIView's width and it should automatically resize itself so that its height allows the whole label content to be visible.
I have tried the following:
self.view.frame = CGRectMake(0, 0, desiredWidth, 0);
CGSize fittingSize = [self.view systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
self.view.frame = CGRectMake(0, 0, fittingSize.width, fittingSize.height);
But this changes both the height and the width of the view, not keeping the width at the desired value.
Is there an elegant method to do this?
Thanks in advance for any help?
In AutoLayout, you would need add a width, top, bottom, leading (left) and/or trailing (right) constraints for the view on to the superview and declare properties for at least the top and/or bottom constraints. After adding the aforementioned constraints you could then change the height of the view by adjusting top and/or bottom constraints constant value.
Here is a link to the Auto Layout Guide.
Auto Layout Guide: Introduction

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