I am using scroll view. In my scenario, When contents are added dynamically in content view of scroll view. The view height must be increased automatically and content is added to the bottom with scrolling functionality. I tried the following. There is no particular way of scroll functionality. I don't know why scrolling is much complicated in iOS. Why scroll view not work the way like table view scrolling, table view taking any number of amount and scrolls. Finding youtube videos too not working as it has fixed height in advance .
Inside your scrollview you must add a UIView. Add a height constraint to the UIView and programatically change the height of the UIView depending on the content you are adding to this UIView. This scrollview will work if the height is large.
Reference: Add a ScrollView to existing View
I inserted a scroll view into an existing view and now my page is not appearing and I am not sure how to fix this. My scroll view is under the view so I do not understand why it is not displaying.
With auto-layout, the UIScrollView needs to be able to calculate its content size using the available constraints. This is often best accomplished by adding a UIView in the scroll view to act as the content view, rather than directly embedding UIControl subclasses. The content view can then be constrained to be equal width and/or equal height to the parent view of the scroll view. The variable height/width (depending on the scroll direction) of the content view can be calculated by fully constraining the widgets it contains.
I am so confused about UIScrollView.
I'm working with a view contains many other views. And that view placed in a UIScrollView.
How can I change height of this view?
I've tried so many ways but they didn't work. I tried to change frame by CGRect but view's child went wrong.
First of all you should be using constraints using auto layout.If all the constraints are justified then the there will be no warning.At that moment the scrollview will fit all the views under its contents view and mange the content size of it by itself.
If you want to increase any view in the scrollview to increase in height you may increase the height constraint and the scrollview will manage the constentsize by itself.
I'm trying to implement an iOS collection view which basically should work similar to a table view, but the cells' widths being integer multiples of the collection view's width (eg. 4 times the width). the collection view should scroll vertically (like a regular tableview does), but it should page horizontally across the content.
I do have the custom layout working except for the paging. Currently, the collectionView will just scroll horizontally. I'm unsure how to implement the paging correctly.
If I just set pagingEnabled on the collectionView, it has no effect. I suspect that the scrollview needs to be told what the width of a page is..?
Or do I have to do anything weird because there is only one cell/column per row, instead of multiple cells?
See the image; the grey bars are the cells, the blue rect is the collection view frame.
thanks!
I believe if the collection view item widths are less than or equal to the width of the collection view, then the horizontal paging should work via the pagingEnabled property. Otherwise, you need to create the paging effect yourself using the UIScrollView delegate methods and animating to offsets yourself after a certain threshold
I have a simple screen, with a slider and a label positioned next to each other horizontally. I have embedded these inside a UIScrollView (I set this to fill the screen and used 'Add missing constraints'), because I will need vertical scrolling later down the line. I don't however, want horizontal scrolling. I have seen numerous posts on here and other sources about people wanting to disable horizontal scrolling, however I'm not sure that's what I want to do, I think I need to restrict the UISlider from causing the horizontal scrolling; I think it is trying to take up more width than the screen. I have added what I think are the necessary horizontal constraints:
Leading space to container for the UISlider
Horizontal spacing to the UILabel, and
Trailing space to container for the UILabel
But this still causes horizontal scrolling, and the UISlider's are the cause, they are taking up more room than I want, as seen below:
I have tried disabling horizontal scrolling in the code using a few techniques, one being:
func scrollViewDidScroll(scrollView: UIScrollView) {
if scrollView.contentOffset.x>0 {
scrollView.contentOffset.x = 0
}
}
but this does not seem to stop the horizontal scrolling.
Can anyone offer any suggestions?
Thanks in advance.
My suggestion is to never use Add missing constraints. It never does what you really want.
Here's the problem. You are laying out your UI on a ViewController in the Storyboard that is square. Apple did this to remind you that you need to be flexible in your design, but it doesn't match the size of any device. When you Add missing constraints, it uses the absolute dimensions of that square to create the constraints which are certainly wrong.
In your specific case, it is giving the slider a width that is too wide, which is why the slider goes off the right side of your screen.
Here's the trick about scroll views. If the contents inside of a scroll view are wider than the scroll view itself, then that content will scroll. The same applies vertically: if the contents inside of a scroll view are taller than the scroll view, then the contents will scroll.
In order to design this to work on all phones, you need to make sure that the contents of the scroll view are laid out correctly for each phone size. Which certainly means you don't want to use specific widths for both the label and the slider because you'll end up with the wrong width for some device, if not all of them.
The best way to do this is to:
Drag out the scroll view and add it to your ViewController. Add constraints to make sure it is properly sized on all phones, such as attaching it on all sides to its superview with a fixed distance.
Drag out a new UIView and drop it on the scroll view. Drag its edges until it exactly matches the size of the scroll view. This will be your content view. Pin all four edges of this content view to the scroll view with offsets of 0.
Here's a tricky bit. Even though you've pinned the content view to the scroll view, its size of free to grow because that is what allows it to be bigger than the scroll view itself and allow there to be content to scroll over. To keep your scroll view from scrolling horizontally, you need to make sure the content view has the same width as the scroll view on all devices. To do that, find the scroll view and the content view in the Document Outline to the left of the Storyboard. Control-drag from the content view to the scroll view and select Equal Widths from the pop-up.
You still haven't told your content view how tall it should be. For now, give it an explicit height constraint of 1000. That will be enough to scroll.
Now, add your label and slider to the content view. In addition to constraining them to each other and to the edges of the content view, you will need to give your label a width constraint. Then Auto Layout will have all of the information it needs to compute the width of your slider. Auto Layout knows how wide the content view is (which will be different on different devices), it knows how wide your label is, and how far everything is from everything else, so it will just stretch the slider to fill in the rest.
If you do all of this, you will have a UI that is properly sized for all devices in all orientations that scrolls vertically.
Just embed all view in your UIScrollView in a UIView, give it the required constraints then the slider and label will stay.
That worked for me just now.
UIScrollView is special when you want use AutoLayout with it, subviews can not be added directly, it needs a container view to constraint the contentSize of UIScrollView, Auto Layout Guide:Working with Scroll Views explains the detail reason, and you can find many solutions to solve UIScrollView's auto layout on Google, Such as this answer.
To be honest, it's confused and complicated to understand UIScrollView's auto layout, but if you overcome this, others auto layout question is easy to resolve.