When tableView is scrolling with high speed, and user tries to stop it by touch, tableView keeps scrolling. And user can stop scrolling tableView only after two or three touches. If speed of tableView scrolling is low, tableView respond touches well.
The tableView displays cells with a lot of subviews, and I localized problem on one view.
If I set problemView.userInteractionEnabled = NO, scrolling works well. To set userInteractionEnabled = NO for all subviews of problemView but not for problemView, do not help.
Here image of diplaying cell, the problemView is view with red frame.
Could somebody to give an advice, how to solve the problem?
There are several possibilities:
Your custom view, or one of its superviews, has userInteractionEnabled set to NO.
There is another view on top of your custom view, or on top of the table view within the custom view.
The custom view that the table view is inside is smaller than the table view (with clipsToBounds=NO, a subview that extends beyond the bounds of its parent can be seen but not normally interacted with). Or the same for another view in the stack.
The custom view (or one of its superviews) overrides pointInside:withEvent: or hitTest:withEvent: incorrectly.
It might be that it thinks you are editing it in some way. Try allowsSelectionDuringEditing = YES. Here is more information with using the UITableView.
If you are using NSTimer inside the UITableViewCell then I have experienced anomalous actions as you have discussed. In such case you need to replace implicitly scheduled timer with explicitly scheduled timer.
For me the problem was that having userInteractionEnabled = true with a click handler on subviews in the cell broke the scrolling. Not sure why this is the case though. I solved this in my case by using didSelectRowAt on the tableview instead of having custom click handlers on the subviews. Then both the scrolling and the click handling worked as I wanted to.
Related
I want to add a subview to a UICollectionView in order to make a left panel that scrolls with the collectionview.
Using
[self.collectionView addSubview:myView]
all touches become disabled and I can no longer scroll the view. I've read that adding a subview to a collectionView like this is bad practice.. is this true? Why does it disable touches from reaching the collectionView event when
userInteractionEnabled = NO
I'm trying to do this: imgur link by grabbing the frame position of the first cell in each section, and adding a dot with to myView with the same y value.
Thanks for any help!
Adding subviews using the addSubview: method to a UICollectionView is very bad practice. It can cause a lot of different problems in the normal behaviour of the CollectionView. It can obstruct the views underneath it, capture the touch events, preventing them from reaching the actual scrollView inside the CollectionView, etc. The subviews added using this method will also not scroll as the other elements in the CollectionView do.
The correct way to do what you want is to implement a new type of UICollectionViewCell for the dots, and compute their locations in the prepareForLayout and layoutAttributesForElementsInRect: methods. Basically you'll have either one or two cells in each row. Which ones will have two rows will be determined by you in the methods I've mentioned.
In fact, Apple's docs have a perfect example that's even more complex than what you're trying you achieve. You should check it out from this link.
May I know the purpose of that scroll view ? Because, if you're looking for a subview that displays only a label or image etc., You can use custom collectionview cell instead if I am not wrong... Hope it helps :) :)
I have a tableview which will not budge when touched. It is very confusing to me. It is the most recently added subview (I checked - it is the last entry in my view's subviews array) and for some reason it just won't scroll up or down. If I tap multiple fingers wildly on the tableview it will one in a while highlight the cell under one of my fingers, but it will not scroll even a little. I have set the number of rows to 100 (many more than are visible on screen) and I have set the 'bounces', 'scrollEnabled', and 'userInteractionEnabled' properties to YES.
I know that I have not provided much to go on here, but if anyone could at least give some tips on how to go about debugging this I would be very grateful. Can I log from within the tableView gestureRecognizer handling method? Can I test where my touches are going?
Please help!
Thanks.
A TableView is basically a specialized ScrollView. If it's not scrolling, it seems to me it could be one of two things. Either something is on top of the TableView and is capturing the gesture events before the TableView can get them, or You have set the bounds and contentSize incorrectly. For a TableView or ScrollView, the bounds of the view should be the visible area, and the contentSize (should be handled by the TableView without you needing to do anything) is the size of all the cells in the Table.
So I would check the bounds of the table view and make sure you are setting that to the contentSize, since that would cause it nor to scroll.
Just to make sure it's on the top, try calling
[view bringSubviewToFront:tableView];
In my case tableview "User Interaction" was disabled. I just enabled it & works.
In my case, tableView "canCancelContentTouches" was not enabled. I set it to true in the storyboard.
Can you check the frame of the parent on which the tableview is added? Make sure the parent view have correct frame to include the table view. I have faced this issue sometime back my table view was not responding to touches and there was some problem with frame size. Also do check the bounds and frames of your tableview
-anoop
Please check tableview scroll is enabled.
I just hate XIB and Storyboard. After 30 mins of debugging it come to know that scroll was not enable in XIB.
Thanks
Basically, Table view is just a kind of scrollview. So in case it is not scrolling You should be sure that if the frame size of your table view is less than the contentSize of your table view. For this just log the frame and content size of tableView's scroll view. If you found that frame size is greater or equal to your content size, just correct your layout constrain of your view. And I hope it will work.
I'm creating my views programmatically. I have a UITableView in my UIViewController subclass that I want to add a scrolling subview to that is not a cell. I want to add some text-based subview to the UITableView that scrolls with the table and starts out above y=0 so the user will only see it if he pushes the table down. That is, it should reside above the first section of my table. If it helps for visualization, I intend to make something similar to those "scroll down to refresh" features and want some indication to the user that scrolling down causes a refresh. Is there any way to do this without something messy like using another UITableViewCell to represent it or abusing the UITableView delegate methods to move a view around whenever the user scrolls?
Simply using [tableView addSubview:] in my viewWillLoad only makes it appear for a split-second then disappear once the table data is loaded. This seems weird to me because UITableView is a subclass of UIScrollView, which is meant to hold other views in it. Using [tableView.backgroundView addSubview] does nothing.
P.S. Why not use a UIRefreshControl for this? I'm still undecided but leaning towards not using one because I don't like how slow that spinning wheel "feels" when the refreshes are usually very very quick. I've been looking at other options like flashing the background subtly and only showing a wheel if it's taking a longer time than usual.
I You can implement pull to refresh with only a table view
To do this using the scroll view delegate, since tableview is a subclass of scroll view.
Set view controller to be the tableview delegate and implement
(void)scrollViewDidScroll:(UIScrollView *)scrollView
When scrollview content offset y value passed a point, add a label to the viewcontroller.view not tableview. When you scroll back or release, remove the view.
You might also be able to add label to the table view and set the frame origin to negative y value, so when you pull the label will move into view (Never tested this do might not work)
I have added a subview to my tableview and when ever the user scrolls the tableview, the subview scrolls with it. How do I prevent this? I know it's probably along the lines of not adding the view to the tableview's subviews, but I have no knowledge of any other ways to do this. Thanks.
If you want to make a view a subview of the table view, then you can make it floating (non-scrolling) by changing its origin.y value in the scrollViewDidScroll method.
-(void)scrollViewDidScroll:(UIScrollView *)scrollView {
self.iv.frame = CGRectMake(self.ivOrigin.x, self.ivOrigin.y + self.tableView.bounds.origin.y, self.iv.frame.size.width, self.iv.frame.size.height);
}
In this example, "iv" is a property for an image view, and "ivOrigin" is a property for the initial origin of the image view (defined when I created the image view and its frame in viewDidLoad).
The UITableView is built and intended to be a view of things that scroll.
So, you can either fight that, which as you're discovering is quite hard since everything about the component is built and focused around scrolling and fast display of a subset of the full list data... Or, you can not fight it and put your static item on top of the table as a fixed-position item.
If there's a reason you can't add the table view and your animate-out item in your main view, you can always add a custom UIView class that contains both the table view and your animated view. Have your custom view class expose the contained table view as a .table property, and the container you're putting things in can be tweaked to use "mycontainerObject.tableview" instead of just "tableview" where needed.
Yes, it's a little more work to write the custom UIView subclass and give it a couple properties to hold the UITableView and whatever UIView you're animating out.. but it's likely a lot safer in the long run than trying to "hack" into the UITableView's methods and view hierarchy to try to give it a "fixed in place" behavior.
I have an app with a TableView which is contained inside a ScrollView (horizontal pagination).
In each TableView is a custom TableViewCell which has a number of views.
To handle a singular tap on an area within the cell, I add a UITapGestureRecogniser to views within the cell.
Rendering performance is fine. But when I tap, I notice a sizeable delay from the point of tapping, to the point where the selector is called (i.e. I believe most of the time is being spent inside UIKit doing hitTests and finding out which element responds to what).
Is there a way to make this faster? What should I be looking out for that may be causing this problem?
You could try adding a single tap recognizer to a transparent view that fills the cells contentView, add it last so it's front most in the subViews array, then have it to the hit test for just the views of interest.
That said it would seem the delay comes from some other interaction.