Slider inside Horizontal scroll view issue in IOS - uiscrollview

My layout has severalsliders in a scroll view which scrolls horizontally. The issue is when I try to drag the slider thumb it is not moving instead the scroll view itself scrolls horizontally. How to fix this? (In Swift)

Swift 3 Solution
I was facing a similar issue and fixed it by setting
scrollView.delaysContentTouches = false
Explanation
According to Apple Docs
If the value of this property (delaysContentTouches) is true, the scroll view delays handling the touch-down gesture until it can determine if scrolling is the intent. If the value is false , the scroll view immediately calls touchesShouldBegin(_:with:in:)
. The default value is true.
As the word suggests it delays the content touch (i.e lowers the priority of subview's action) leading to irresponsive subview content updation during scrolling.
When this property is set to false it gives priority to the subview's action (by immediately calling touchesShouldBegin(_:with:in:)) leading to responsive subview content updation.

Maybe you call UISlider "Lazy var". Let's change it to "Let"

Related

How to fix scrollable content size ambiguity in xcode 11 using auto layout beta 7 UIKIT

When using Auto Layout, I am unable to set up a simple UIScrollView in my view controller in Xcode 11 beta 7. I know that I must constrain the scroll view to the edges, and then set the scroll view width and height equal to the width and height of the entire view that contains the scroll view. However, I am not getting the option to set equal widths and heights when I attempt to do so.
When I do the right-click-drag from the scroll view to the entire main view, I get the following options:
Leading Space to Safe Area
Top Space to Safe Area
Trailing Space to Safe Area
Bottom Space to Safe Area
Center Horizontally in Safe Area
Center Vertically in Safe Area
In other videos, there is an "Equal Widths" and "Equal Heights" option that I don't seem to have.
Am I doing something wrong, or did Apple change the way scroll views work in Xcode 11?
I'm using beta 7 currently
I was finally able to successfully add a UIScrollView using storyboards in Xcode Version 11.0 (11A420a) after much trial and error.
You can add the scroll view directly to the root UIView of the VC or, if you needed to, add it to another UIView under the root view as needed by your UI Design. Constrain the UIScrollView parents normally for whatever your needs are.
Here is the key : when you add the UIScrollView to the storyboard, click on the Size Inspector with the UIScrollView selected. You have to UNCHECK the box that says "Content Layout Guides".
If you do this you can set the scroll view's contraints normally (I did 0-0-0-0 to superview). Then I added a UIView to the scrollview and set it's constraints to 0-0-0-0 and a height of 900 (which is what I wanted).
This will give you constraint errors in red when you set them. They will be fixed by setting the width of the UIView equal to the width of the UIScrollView.
Set the UIView width equal to the width of the UIScrollView view by Ctrl-right clicking on the UIView, dragging to the UIScrollView, and selecting the "Equal Widths" option. This should get rid of your constraint errors.
You actually can then go back to the UISCrollView Size Inspector and check the "Content Layout Guides" checkbox, no constraint errors will appear.
Disable the content layout guides in scrollview properties.
Hope it helps.. :)

iOS11 paged scroll view suddenly is scrollable vertically

I have an app which uses EMPageViewController to display a set of onboarding slides. My understanding is that the underlying scroll view is using paged mode to display slides.
Upon update to iOS11, I see that suddenly the slides follow the finger, so they are draggable and bounce up and down. I expect paged scroll view to be scrollable horizontally only.
How can I restrict paged scroll view to horizontal scrolling only in iOS11 ?
I tried this but it did not work
pageViewController.scrollView.alwaysBounceVertical = false
This fixes the issue:
if #available(iOS 11.0, *)
{
self.scrollView.contentInsetAdjustmentBehavior = .never
}
The behavior for determining the adjusted content offsets. This
property specifies how the safe area insets are used to modify the
content area of the scroll view.
contentInsetAdjustmentBehavior is new from iOS 11 > and the default value is automatic.
Content is always adjusted vertically when the scroll view is the
content view of a view controller that is currently displayed by a
navigation or tab bar controller. If the scroll view is horizontally
scrollable, the horizontal content offset is also adjusted when there
are nonzero safe area insets.
Which made some of my UIScrollView scroll more than they were excepted to.

OS X App - Cannot Resize App Window

I have an OS X app originally built using Xcode 4, now using Xcode 7. When "springs-and-struts" was superseded by constraints, I reworked the UI to use constraints. Simple enough, and seemed to work well.
Fast forward two years after first release, and for the second release I needed to add controls and increase the height of the main app view. Unfortunately, my test team is using smaller screens and cannot see the whole view. They need to resize vertically.
Problem - even though the resize controls box is checked, the window cannot be resized. The controls do not show at run time. I tried
Setting lower minimum window content size height, but that did not change anything.
Changing content compression resistance did not change anything.
I am thinking this issue has something to do with constraints.... Any ideas on how to get resize to work?
Edit: After playing with a new test app some, I am more certain the problem is due to constraints. I have a control where I have constrained leading and trailing space to superview and width - there went horizontal resize.
I really need to have a view where the user can resize the window, but scroll the content. However, in this case, the content is other controls. I think on iOS, I would use a UIScrollView. On OS X, I have tried a scroll view control and have tried embedding in a scroll view, and neither have the desired effect.
I had the same issue and solved it by adding a view to be used as a "container" in the view controller.
Pin the top left corner of the "container view" to the view controller (leading space 0 and top space 0). Add equal width and height constraints on the "container view" to the view controller. Then move all your objects into the "container view" and add your object constraints on the "container view" not the view controller.
In my case, it happened in this way (Xcode 13.1).
I mistakenly added a view from IB outside of the window view hierarchy. The new view was added as a separated object (a top node in the interface builder file). I added the new view into the window by drag-n-drop.
I found the new view had different behaviours, for example, I couldn't set the top space constraint. With this view in the view hierarchy, I couldn't change the window size (content view size) at all.
I removed the view and added another in the view hierarchy, it worked as normal.
I think IB initialises the view differently if it is a separated object (top node of the interface builder file).

UIScrollView contentInset is set to nonZero when using autolayout

So I have the following view hierarchy :
A full size scrollView in my viewController's view with the following constraints :
These are the constraints on containerView (ignore the second last one, its a hacky semi-fix for my problem):
I have the status bar, the navigation bar and the tab bar visible.
The thing is that when I set a breakpoint to check the scrollView's contentInset, it shows 64 on top and 49 on bottom, left and right are zero.
There is no way to set contentInset in IB, I tried setting it in an IBAction to UIEdgeInsetZeio, but that didn't fix it either. This is screwing up my scrollview by adding space above and below my contentView, how can I fix this?
By default the view controller extends the view under the top navigation bar so your content will blur under a translucent navigation bar. This is controlled by edgesForExtendLayout which is managed in Storyboard via the Extend Edges setting.
By default, the scrollview will automatically adjust its content inset so the content appears below the top layout guide. This is controlled by automaticallyAdjustsScrollViewInsets which is also managed in Storyboard.
What you did was constrain the top of your scroll view to the top layout guide instead of the top of its superview. By doing this, you manually offset it by 64 points. However, the scrollview is still automatically insetting its content by 64 points, which is why you're seeing additional space above and below your scroll view.
Either constrain your scrollview to its superview (so its content scrolls under the top/bottom bars), or disable the view controller from automatically adjusting the scroll view inset.

UIScrollview scroll not working

UIScrollview scroll is not working when i tested application in device (iPhone 5), But scroll is working properly in iPhone 5/5s/6/6 Plus simulator. I am developing application using Xcode 6 and UIStoryboard with AutoLayout.
I set the top, bottom, left and right constraints of UIScrollview with relative to Superview. And i also set the constraints of every UIControl which is in the UIScrollview.
Has any one have solution regarding this issue?
Please see below screenshot for reference.
It's probably easiest to have the scroll view contain a single view, which then contains all of your scrollable content. That single view should be anchored to all 4 sides of the scroll view, and if it's only meant to scroll vertically (which is what your screenshot makes it look like), then set the content view to be the same width as the parent of the scroll view.
To make sure an UIScrollView scroll, you have to check
Size
Your content View is bigger than your Scroll View. If you want it to be scrolled vertically, make sure its higher; horizontally, wider.
Constraints
Make sure your Scroll View is pinned to its super view, Top, Bottom, Leading, Trailing.
Make sure your Content view of Scroll View DOES NOT have CenterY constraint set to Scroll View, cause that'd make content view stuck with Scroll View and it'd never be able to scroll. (That happens to me the last time I was stuck)
Interface Builder settings
Make sure the check in Interface Builder under Scroll View is checked:
Scrolling section, Scrolling Enabled.

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