I'm writing an ios application, which has child views (like fragments or subviews) which are placing in a simple UIView in a UIViewController and the height of UIView is approx 300px. Im just loading subviews in UIView, however every subview has its own content that may not be fit in 300px thus uiscrollview cannot got though out the last view.
My problem is, Im unable to solve the scroll view content in order to scroll from parent UIViewController along whith its child view controller subviews, as the subviews are longer than 300px and thus uiscrollview is unable to get te last element.
I tried to to give static scrollview.contentSize.height = 1000 and hence the scroll view can scroll below the screen but im unable to click on the later views as it seems uiscrollview is unable to read that element.
My question is, how can i assign dynamic uiscrollview height assuming that im using autolayout in my uiviewcontroller and I want to calculate scroll height according to children based in my UIViewController. Im using swift 2.0 and autolayout in storyboard.
Your constraints should be like,
scrollview - top,bottom,leading,trailing
view (content view) - top,bottom,leading,trailing,fix height and horizontally center in container
and add your all other stuff in that view. you will got desired result. it will scroll in small screen size then content view and will not scroll for bigger screen then content view.
second thing you need to increase height of your content view as more subviews add. your content view's height should be equal to all subview's height and spacing
After this setup if you unable to scroll then check content view's bottom constraint's constant in size inspector. make it zero (if unable to scroll then only).
hope this will help :)
Related
I am having trouble with layout in Interface Builder (Xcode 9 / iOS 11).
I have a UIScrollview and over it I have 2 buttons (next and prev view).
If I put the buttons under the scroll view, they appear and work. But if I put them over the scroll view, they don't appear anymore.
What can be the problem?
Layout buttons and scrollview:
Warning message:
Drag scrollview
Constraints
You need to understand first how UIScrollView works. Check again the Warning Message. It says:
ScrollView has ambiguous scrollable content
It means that the subviews of your scrollView does not have enough constraints attached to them and to the scrollView to make the scrollView scroll. Well how does the scrollView scroll? If the content of the scrollView exceeds the frame (either width or height) of the scrollView, then the scrollView will be scrollable.
In your problem, the two buttons do not push each other to the scrollView's frame, is this clear? It means your buttons do not have enough constraints.
I'll try to provide an example in a bit.
When working in Interface Builder, if you drag and drop one object onto a container object - such as a UIView or UIScrollView (which is also a UIView), the object will become a subview of the container.
That makes it a little difficult to do what you want, which is to have the buttons on top of the scroll view, NOT as subviews of the scroll view.
As you see in this image, the buttons are clearly NOT subviews of the scroll view:
In this image, I drag/drop the buttons onto the scroll view, and they become subviews:
So, to get what you want, add the buttons outside of the scroll view and set their constraints. I gave Prev a leading constraint of 16 and Next a trailing constraint of 16... both constrained to the view, not the scroll view. Then I constrained Next to be centered-vertically to Prev so they will stay vertically aligned to each other.
Then give Prev a centered-vertically constraint to the scroll view. Select Editor -> Update Frames and the buttons will move into position, but - as you can see from the Document Outline - they are not subviews of the scroll view:
At this point, you can drag-scroll any content you add as subviews of the scroll view (such as the image view here) without affecting the buttons:
I'm assuming you want your buttons over (and not under) the scroll view. That's easy enough in Xcode 11 Interface Builder, which lets you pin subviews of scroll view (i.e., its content view(s)) to either the Frame Layout Guide or the Content Layout Guide or a combination of either.
The frame layout guide defines the size of the visible area of the content view by applying width and height constraints based on any superview other than the scroll view or its container (in other words, another sibling subview to the parent view containing the scrollview).
The content layout guide defines the size of the overall area of the content view any applying width and height constraints of based on same, which is, or course, larger than the frame of the scroll view:
Using these layout guides obviate the need to toggle scrolling in either direction; constraining the Content Layout Guide to a height or width of the visible frame of the scrollview determines whether it can be scrolled vertically or horizontally.
That means that, if you constrain a subview of the scrollview to the Frame Layout Guide, it will not scroll (and, yet, will be a true subview of the scrollview).
The
Frame and Content Layout Guides added to the UIScrollView Interface
Builder component in Xcode 11 is not yet documented; however, Apple
still distributes an out-dated document that describes how to create > a "floating view" in a scroll view with Xcode 10 or earlier.
I wanted to add some labels and textfields on my view and that view should scroll, so I am thinking of putting view on scrollview.
I wanted to add some labels and textfields on my view
And that view should scroll
So I am thinking of putting scrollView
And then I wanted to put my view having labels and Textfields
Is it possible?
Please check scrollview property Bounces Vertically is checked or not if not check it
May be, your content is less, than ScrollView, that's why scrolling is disabled
Put view with labels in scrollview. Scrollview should be less in height than view. View should have height considering all ui cvontrols in it. should work like this
Make sure your scroll view height is not greater than view its content size has to be greater as all people says. You get confused between content size and scroll view height.
Meas using nib suppose your scroll view height is 300 and when you use the code content size should be greater than 480 so it will be scroll-able on iPhone 4 size device who's height is 480
To make sure your constraints are well defined, first check these steps:
Make sure your base view is a UIView
Put into a UIScrollView and add constraints to the edges of UIView
Put into the scrollview a UIView and add constraints to the edges of the scrollview. I call this "content view".
You should assign a width to the content view. I usually set the width of the content view equal to the width of the scrollview.
Put your labels/views/images/whatever into the content view and use autolayout constraints to resize them automatically to fit the target screen.
Please consider that:
Your scrollview must always have a height, fixed or dynamic. In order to avoid errors with autolayout, consider that:
the last element on the bottom of the content view must always have a constraint to the bottom edge of the scrollview, or
the content view must have a fixed height
If the height of your content view is less than the height of the scrollview, the view will not scroll. You should add more views or more margin to the bottom constraint of the content view.
I'm trying to allow the scroll view to adjust size depending on the size of a subview on this page. All of the other constraints for the objects in the picture work fine.
When I add constraints to my subview to hug to the left, right, and bottom of the screen (and the top of the subview hugs to the bottom of the segmented control) and then update frames, it makes the height of the subview 0.
I can't add a height constraint to the subview because the size of the subview will change dynamically depending on the amount of content in it, which will then change the size of the scroll view.
How can I accomplish this without adding a height constraint?
Your view hierarchy should look like :
Create a single child view of the UIScrollView where we will put all
of our content
The content view has to be an explicit size (or a placeholder size in
interface builder and set at run time). In other words your content
view cannot depend on the scroll view to get its size. It can,
however, depend on views outside of the scroll view to get its size.
From Apple Technical Note TN2154
Set translatesAutoresizingMaskIntoConstraints to NO on all views
involved.
Position and size your scroll view with constraints external
to the scroll view.
Use constraints to lay out the subviews within the
scroll view, being sure that the constraints tie to all four edges of
the scroll view and do not rely on the scroll view to get their size.
UIScrollView And Autolayout
Using UIScrollView with Auto Layout in iOS
Try giving the Equl Heights & Equal Width constraints to your Subview.
I've been facing this issue from past 2 weeks and not yet got a solution.
I'm using UIScrollview in my application where the problem exists.
Generally in my app, there is dynamic text and images with different sizes will come from webservices. For example, imagine the Facebook Newsfeed. My application is similar to the Facebook newsfeed. Sometimes, there will be only text, sometimes there will be text and images. And comments for that post.
As i've seen in many links, the heirrarchy i'm following is SuperView-->UIScrollView-->Content View and the elements are placed in that content view. I'm assigning the constraints from the elements in the contentview to the Superview (ContentView --- constraints -- SuperView). When the content in the view exceeds the size of the superview, it has to scroll. But the scrollview content size is limited to the size of 600x600 i.e., in main.storyboard, when we design for W any x H any size. I've seen many tutorials and searched many sites. But following them gives me no luck.
Any help is appreciable.
Here is how to set up a scrollView in Interface Builder from scratch that works with Auto Layout.
Start with a new ViewController. Drag out a scrollView such that it fills the view. Untick Constrain to margins and constrain the left, top, right, and bottom edges of this scrollView to the left, top, right, and bottom of its superview with offsets of 0. This allows the scollView to fill the screen on any device in any orientation. You can make your scrollView take up less of the screen if you like, just make sure it is fully contrained.
Add a view to your scrollView. This should be the only top level view on your scrollView and it will serve as your contentView.
Constrain the left, top, right, and bottom edges of this contentView to the left, top, right, and bottom of the scrollView with offsets of 0. At this point, you will see warnings about ambiguous content size. That is because you haven't told it yet how big your content view will be.
To size the contentView, add width and height constraints to the contentView. If you want it to scroll, the width and height must be larger than the width and height of the scrollView itself. If you only want to scroll vertically, set the width of the contentView to be equal to the width of the scrollView. To do this, in the Document Outline view, control-drag from the contentView to the scrollView and select Equal Widths from the pop up.
If you want to be able to change the height of your contentView from code (to account for dynamic content), first create a height constraint for your contentView by control-dragging within the contentView and selecting Height from the pop up. Create an IBOutlet to the height constraint by control-dragging from the height constraint (found in the Document Outline view) to your ViewController's code. Give the outlet a name like scrollViewHeight then set the height with a value like scrollViewHeight.constant = 2000 when you need to change the scrollView's height.
Simply add your UIScrollView to your UIViewController's view in the storyboard and add the appropriate constraints in the interface builder.
Then, build your content view in the code and give it any frame you want, now start adding your controls to this content view and calculate the size of each one (especially the height), and at the end you have the total height of your controls.
Now set the frame of the content view to match that height and add it as a sub view to your scroll view, then set the content size in the code like this:
_scrollView.contentSize = contentView.frame.size;
Another note, do this changes to the sizes in the viewDidLayoutSubviews to avoid any problems with different screen sizes but be careful, this event is called many times so have a BOOL or something to ensure that the code that creates the view and add it to the scroll view is executed once, e.g. like this
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
if (! built) {
// Do everything I explained above here
built = YES;
[self.view layoutSubviews];
}
}
I have a scrollview which has two subviews (iPad). The view hierarchy is as follows:
-- UIScrollView
-- UIView1
-- UIView2
The frame of the UIScrollView is the size of the screen, the frame of UIView1 is also the size of the screen, but the frame of UIView2 is (0,0,768,2000).
The scrollview doesn't scroll vertically. According to the apple documentation, the scrollview should automatically set its content size. Can anyone help me out with this issue as why the content size is not being set properly ?
P:S: When I use a single view inside the scrollview and set a proper vertical constraint, it scrolls properly.
Scrollview won't scroll if you enable autolayouts. Technically when you scroll, all the elements in the scrollview change their position. So use auto layout if you are fixing the position of the elements in the scrollview.
Instead use a UIView as a container view inside a scrollview which contains all other objects like button , label, imageview etc. And then you will be able to scroll.
Check the below link for more details:
https://developer.apple.com/library/ios/technotes/tn2154/_index.html
In your problem try to put proper values of content size. Also check if the vertical scrolling is enabled or not.
The question is old, but the correct answer would be to make sure the autolayout constraints are all set.
Vertically, you should have some constraint pinning your View1 to the Scroll View Top, another one pinning your View2 to the Scroll View Bottom, and one third one setting the vertical space between View1 and View2. Also check that the views themselves (View1 and View2) have constraints for their heights.
Horizontally, pin one of the views to the Scroll View in both leading and trailing space, and the other view left and right to the first one (so they will have equal widths).
Once all of those are set, the content should scroll correctly.
Use contentSize property of scroll view in code. The best way is to use 'viewDidLayoutSubviews' method
(void)viewDidLayoutSubviews
{
[super viewDidLayoutSubviews];
_scrollView.contentSize = CGSizeMake(568, 594);
}
2.Always make horizontal space >=0 between lowest of inner views and a scroll view. Automatically, auto layout make suggestions like '-160' and this negative space will not scroll.
If the Content size is more than the scroll view frame then only scroll view scrolls otherwise not .
Main Point : Mistake is in set 'contentSize' of 'UIScrollView', you need to set manually.
As seem in your Question
scroll view frame = screen frame,
view 1 frame = screen frame,
Its okay but
view 2 frame = (0,0,768,2000), then it overlapping on first view because your view2 x,y position is (0,0), so may be your first view will not display.
If you want to vertically add view 1 after view 2 then your view 2 frame should be
view2.frame = CGRectMake(0,view1.frame.origin.y + view1.frame.size.height , 768,2000);
And after added both of view then you need to manage contentSize of UIScrollView , in your case such like
scrollView.contentSize = CGSizeMake(768, view1.frame.origin.y + view1.frame.size.height + 2000)
I put simple logic, That may be helpful in your case:
How to enable scrollview scroll automatically when used with AutoLayout:
Please see the below link which help you to fix it correctly:
https://medium.com/#pradeep_chauhan/how-to-configure-a-uiscrollview-with-auto-layout-in-interface-builder-218dcb4022d7
Question for above help guide:
Which view is parent view?
scrollView or parent of scrollView?
Answer:
- Parent Of ScrollView (Give equal with and Equal height to view which is parent of scrollview)