Uicollectionview reload cell. Commented Jun 29, 2015 at 10:29 .

• Uicollectionview reload cell I have a problem with data reloading using UICollectionView. That means cellForItemAtIndexPath will be called for lots of cells. I can confirm that Payal Maniyar's solution also works for UICollectionCompositional layouts as well. Below is the code i have. I originally had [self. Every new game, i change the number of cards in the game. I'm finding that if my NSArray holds Obj1, Obj2, Obj3, then at first, the UICollectionView correctly maps Obj1 to the first collectionViewCell, Obj2 to the second, etc. The scrolling performance is good, however, sometimes the tapping to swap players does not respond. Indeed, when animatingDifferences is true , you can apply a snapshot that reverses the cells, and yet configure is never called again, because moving the cells around is all that needs to be done: I have a probem when trying to reload a UICollectionview in iOS. If I Using reloadItems(at:) is part of the correct answer, but the code you posted submits an empty array of indexPaths, and therefore doesn't make sense. Follow asked Apr 3, 2016 at 21:35. Ask Question Asked 6 years, 7 months ago. 5) { // call reload cells in the animation block and it'll update the selected cell's height with an animation collectionView. 2. This works fine. count } func collectionView Hi, I'm trying to create a UICollectionView where the cell high is automatic. cellForRowAtIndexPath doesn't get called after calling reloadData in UICollectionView. Because the words differ in size i've added the following, to prevent long words from being cut off: layout. When I load the data into the collection view initially, the data is perfectly sized the way it should be. However, the reload does not have the expected behavior. in this case each cell having images get download at a time then it showing memory warning. List item 2. collectionView. I would like to change my entier array used to created all my cells with a button and then reload my collection view, but it is not working. The proper way to get a cell to update is to update the model, then reload the collection view, which will call cellForItemAt If collection view reload the "AD cell" each time when it off-screen then visible again. animate(withDuration: 0. In your case it looks like your model is self. tableView numberOfRowsInSection:([self. collectionView indexPathsForSelectedItems]; // Delete the items from the data source. ID> and load the relative section/item from a property stored on the view controller. count } func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: UICollectionView Reloading cells backwards. Modified 6 years, 7 months ago. " I would like to animate the reload of a collection view such that when a cell is selected I get an animation similar to dealing cards in a solitaire game. movies == nil { return 0 } return self. UICollectionView, layout collectionViewLayout: UICollectionViewLayout I am trying to update the content of the cells in a UICollectionView based on what the user inputs into a textField in the header. I don't know whether you are aware of reload method of tableview and I have a UICollectionView of 20 cells with an imageView inside of them. UICollectionView not refreshing. I want to make it so that I can select a value on the collectionview at the bottom, then be able to drop that value to a position on the collectionview on the top, by ,again, tapping it . backgroundView?. Hot Network Questions Did Superdana manufacture a 66 AC outlet power strip/surge protector? Configure Linux to regularly sync cached data to disk Wouldn't the ban of TikTok violate freedom of speech? I have a UITableView Controller class, and inside of it is a String array. So it should be successful right? after the reload i can still use the collectionView how it normally is used after. If you’ve opted in to email or web notifications, you’ll be notified when there’s activity. I can do this as follows: I can do this as follows: The cellForItemAt method is what updates your cells. 6. I assign image to imageView in cellForItemAtIndexPath and when user touches the cell i change image and run mycode then reload the cell. item == 0) and tutorialCell (all other cells) which has a tableView and can scroll its It seems different between UICollectionView and UITableView. UIView. I don't know whether you are aware of reload method of tableview and collectionView. When I used to reloadData() it updates only visible cells, the remaining cells will update after scrolling down. members. collectionView performBatchUpdates:^{ [self. Unfortunately if user touches and holds any cells during my app calls If you give the cells a colored selectedBackgroundView, the cell you held down during the reload never appears to go back to the unselected state -- however, if you log the selected state, it shows func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { //#warning Incomplete method implementation -- Return the number of items in the section if self. I lost two days on it because I could not understand what was happening, and now that I applied your solution and that it works, I still do not understand why Hi, I'm trying to create a UICollectionView where the cell high is automatic. (Imaging old MS solitaire card dealt) I've searched around for "custom UICollectionView reload animatation" and seen solutions such as you can reload the collection for last visible index. and call cellForRow method for all cell. Place this code right after you initialize the 3 variables, inside There's definitely a compromise between accessing and manually updating the cell view content, and calling reloadData on the whole collection view that you could try. override func viewWillAppear(_ animated: Bool) { displayDataForIndexPath() } Which is called when I need to reload data in my ViewController. You can use reloadItemsAtIndexPaths:, method of UICollectionView to reload the first cell. tableView numberOfSections]-1)]; [self. Commented Jun 26, 2013 at 4:53. I put some logs into my code to show how long the system is actually taking to refresh. Alternatively, add the views needed to I have to trigger the download processes for all cells which are all visible and non visible without scrolling the collection view. extension NounsTVC: UICollectionViewDataSource { func collectionView( _ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return cellIds. Okay it took a while for me to understand your problem. I have looked at other similar questions here but none of their answers have seemed to work. The user will 'create' the puzzle by first tapping each cell to change the colour, press the 'insert Hi Timothy, cellForRowAtIndexPath loads the cells that are visible in the view, in my case the first nine. If you are scrolling and a cell becomes invisible, the same object is used again (dequeueReusableCell) and a new content is set in cellForItemAtAs mentioned in the previous answers, before reusing the cell, prepareForReuse() is called on the cell. But, but, My collection view cell blinks every time I reload data. 0 Swift reload collection view with button click not works. When collectionView:(UICollectionView *)cv cellForItemAtIndexPath: is called I place a placeholder on the image of the cell, and start downloading the image from the internet. Does anyone have any idea? Edit. ImageFetcher(postId: self. row]) return cell } func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return urls. I think that is when the collection view is trying to reload the cells. UICollectionView refreshing issue. Reloading a UICollectionView using reloadData method returns Its all work, but, when collection view reloaded (i did force reload after 1 second) some of cells are reused and placed on others, therefore, it show "old" images and subviews. In this tutorial, you’ll work on a photo-browsing app, FlickrSearch, similar to the iOS Photos app, in which you’ll use to learn how to: Implement reusable views for section headers. Refreshing a UICollectionview. The CollectionView is populated by I have a UICollectionView where when cells are selected, they change to a color selected by the user. The content of the cells depends if a level is unlocked. In WWDC 2020, Apple pushes the usability of I'm not seeing why this would take place. If you want every cell to be reloaded: collectionView. Presumably, imageNotInCache means you're storing image in an in-memory cache, Xcode reload just one cell in UiCollectionView. – Its all work, but, when collection view reloaded (i did force reload after 1 second) some of cells are reused and placed on others, therefore, it show "old" images and subviews. Below is the smallest amount of code that reproduces the problem. How do I refresh the view? Is there something wrong with the way I am dequeuing the cell? Overview. This is how it's set up in the cellForRowAtIndexPath, as it uses I have a collection view which has a section with a title and every section has some words. This is my cellForItemAtIndexPath to reload current cell, or . I've created a custom cellview that contains 3 labels and nothing else, pretty basic The issue I'm having is I'm basically refreshing my data at 5Hz, but by refreshing the CollectionView with reload method at 5 times I am trying to update the content of the cells in a UICollectionView based on what the user inputs into a textField in the header. However, that won't solve your problem either. collectionView reloadData]; } completion:^(BOOL finished) { // notify that completed and do the configuration now }]; but If you’re using a custom data source, then whenever you add, delete, or rearrange data in your collection, you use the methods of UICollectionView to insert, delete, and rearrange the corresponding cells. To avoid it, I'm using: How to reload only data section of UICollectionView? 23. Hot Network Questions After the API-Call is done I reload the collectionView with: self. backgroundView = bgView cell. You can check if label's text length is not equal to zero. In order to avoid initializing this I suppose when you reloading section for the first time, collectionView creates new Cell and self. You can use the following rule of thumb: Reset only the values in prepareForReuse() which you set in cellForRow(). When your outlets are set to nil then cellForRow() can't assign new values to UICollectionView cells only display after second call to reloadData. UITableView will return the same indexPath cell after reloadData when dequeue cell. When you reload the view, that previously selected cell is being reused, and most likely not for the same In cellForRow after getting a cell object from dequeueReusableCell I am initializing a new UIView instance and adding it as a subview to my celll. filterCollectionView. Have an NSMutableArray to hold LevelCells. See Also. So, say goodbye to registering cells using identifiers. automatic) If you want to do it depending of your visible sections you will need to get the visible cells like this: table. You need to reload your collection view if you want to call the datasource or delegate method of collection view – Rajat. estimatedItemSize = CGSize(width: 1. Now the following cells will move forward, so the first cell now would be the second one before the deletion, easy to understand, right? func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPat`h: IndexPath) { // Make your item selected in your data source here UIView. performWithoutAnimation {self. estimatedItemSize = UICollectionViewFlowLayout. When this update triggers I call reloadData on the UICollectionView and I have set the cells to change the background colour on [UICollectionViewCell setHighlighted:]. it would select the same item number in every section). I override the draw() function of the UICollectionViewCell to arrange my images when load the cells. I noticed that cellForRowAtIndexPath only gets Try setting all default values of your cell before doing any check: - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath I am developing a card game using UICollectionView. When downloading is done, i reload the cell so the final image is placed properly. reloadItems(at: collectionView. Hot Network Questions UICollectionView will animate and automatically rearrange the cells after deletion. invalidateIntrinsicContentSize() And as Luis Ramirez mentioned, you Hello as you can see in the video link below when I reload the data, for a frame something happens and some ghost cells appear and disappear, it's like a weird animation Is it because of using reusable cells? and if it is, is it preventable cause that's not so pretty and it seems to cause a bit of frame drop with use of CATransition animation (not shown in the video). First, the solution you are trying is wrong. After retrieve data from network, call -reloadData of the UICollectionView and show another 12 images. reloadSections([0])} When this occurs I'd like to remove the cell corresponding to the updated row from the data source, and from the collectionView. 131 1 1 gold badge 1 1 silver badge 8 8 bronze badges. Note, though, that with your code only item 0,0 actually gets updated. Hot self. If you want to reload specific cells: collectionView. The cell size and everything stays the same, the only thing that changes are the label strings themselves and its actually only 1/3 labels per cell thats changing. Update layout based on selection. reloadData() but I need to only reload an indexPath. So, again, move the fetchData method AFTER you have registered all cells , datasources and delegates. UICollectionView reload data Issue; ios UICollectionView cells not refreshing after scroll; UILabel overloading in UICollectionView; I have a CollectionView with custom UIViews in the cell, On reloadData its re-adding the custom UIViews and not removing the ones already being shown. Am i missing something or did i miss type something? UICollectionView cells only display after second call to reloadData. Where I am having trouble is reloading the UICollectionView using the new filteredCategories array. The Datasource object is the content that your app will display within the UICollectionView. Instead of that, you just reload only that part which is necessary when action occurs. So viewDidLoad is a good place to start fetching, after async call completed don't forget to I am trying to build a simple level design but I'm having some trouble reloading the data in the cells immediately when a condition is met. Apple introduced a better way to reload a cell in WWDC21. deviceSize //Tried with different UICollectionView custom cell did not reload. – hatunike. uicollectionview scrolling change cell indexpath. tableView numberOfSections]-1)]-1) inSection: ([self. import SwiftUI @main struct DemosApp_tvOS: I have a timer to reload the visible cells of the collection view every second. If you want a specific section to be reloaded: collectionView. I do not believe the issue is the use of row vs item, though you really should use item. The user can choose to unlock levels they don't have enough points for yet by using a secondary game currency (stars). For reference, To resolve this within our setup (and on time), I ended up making the Diffable data source use the <Section. Can i scroll a collection view that exists in a collection view cell. You can reload your cells using any of I have a UICollectionView which has 12 cells. And it implicitly takes care of cell registration when passed inside the dequeueConfiguredReusableCell. UICollectionViewCells are reused to avoid instantiations, to optimize the performance. 0 UICollectionView reloadData issue. stop the reloading in collection view. The CollectionView is populated by passing the array into the tableview cell, which is a UICollectionView Delegate and DataSource. reloadData() After calling reload data the visible cell's cellforItem is called but my cell values are not updating until I scroll back and forth func collectionV Thanks Abhishek, the array count is not being reset before I reload the collectionView. In certain conditions, on tvOS, a collection view will reset its focus on reloadData(). UIView if bgView != nil { cell. reloadItems(at: [IndexPath]) line written inside cellForItemAt which is really wrong approach because cellForItemAt called many a times leads to infinite loop of reloading IndexPath's. change the data source, then the repective new values of the cell, then call setNeedsDisplay on the cell. It doesn't happen when I do a full collectionView. In this function I want to get the indexpaths, indexPathsForVisibleItems, that are To resize collection view cells, you could reload the collection view and return the size of you collection view cells dynamically in the method: - (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath Xcode reload just one cell in UiCollectionView. Was having some issues with UICollectionView and spacing of the cells. Hot Network Questions UICollectionView has multiple ways of reloading data. Updated: 16 June 2021. At a minimum, all Datasource objects must implement the collectionView:numberOfItemsInSection: You should set outlets to nil in prepareForReuse() because the cell isn't loaded from Storyboard or NIB again. I can imagine, though, if your collection view has more than one section, that only looking at row/item but ignoring section would be a problem (i. text = categories[indexPath. Then in the data application method after the snapshots are applied, it runs through and calculates which cells need to reload their model and invokes a helper method. texts, images, control values). All my cells were - at random - disappearing when I reloaded my collectionView, only if I had one specific type of cell in my collection. UICollectionView Reload UI Frameworks UIKit Swift UIKit You’re now watching this thread. So the number and size of the cells change. If the collection data shrinks as a result of the reload, As a result of all that work behind the scenes, therefore, it knows when it can avoid reloading a cell if it doesn't have to (because it can move the cell instead). Commented Jun 29, 2015 at 10:29 You just want to reload the cell you are updating, using -reloadItemsAtIndexPath: – I would like to animate the reload of a collection view such that when a cell is selected I get an animation similar to dealing cards in a solitaire game. You can add breakpoint in Also how many cells are in the UICollectionView inside the DiscoverController because only one will ever be the delegate. iOS: reload single cell of UICollectionView. I even tried implementing an extension to the UICollectionView which goes through each cell in the section trying to reload its data but that I have to trigger the download processes for all cells which are all visible and non visible without scrolling the collection view. There are only a few items there (let's assume 10 photos is a maximum). It means you code perform extra thing I got a UICollectionView with several cells in it. UICollectionView: reload data, without removing an in-cell animation. Delete selected items from collection view [self. So the way to reload the first cell is: That's how you reload a cell for a given index path. Call this method to selectively reload only the specified items. In that case no need to add that UICollectionView custom cell did not reload. reloadItems(at: [indexPath]) } } I have a UICollectionView with labels inside the cells that change automatically periodically. I have to tap on the empty screen, then the new cell appears with its image. If you app only need to support iOS 15 and above, you can proceed to this article: Table and Collection View Cells Reload Improvements This is the most used method, this reloads all the data, refreshing all the cells in the CollectionView this is what you should use if you have a Collection View that loads all the data at the Reloads just the items at the specified index paths. 17. Setting I am trying to scroll to the bottom of a UITableView after it is done performing [self. Do you know how I can clear out the previous data before I perform the reload? – Ben. you can reload the collection for last visible index. The index path of first cell is row:0 section:0. collectionView. I have a collections view and the view works fine when I load the data initially, but crashes when I try to reload it. So you can overrride UICollectionView Reloading cells but not deleting old ones. reloadData() is called, the screen below is shown and i've to scroll down to find the filtered cells. Words differ in size. when a user clicks on the correct cell, I draw another imageView in that cell (a correctCircle let's call it). UICollectionView after reloadSections: and reloadData the cell is not update UICollectionView ; reloadItems(at:) Instance Method reload Items(at:) Call this method to selectively reload only the specified items. and if you have images in cells , then use image caching , either you can program image caching or use libraries like SDWebImage */ I am facing a challenge where my UICollectionView does not show an item when the collection count is 1. I put some logs into my code to show how long the system is actually How are you reloading the UICollectionView? – Tim. the Problem is when i scroll down, then it automatically repeats data and make more of time. Does someone know how to keep the view after reloading the Drag a UICollectionView object to your view controller; Set proper constraints on the collection view; Set dataSource & delegate of the collection view; Prototype your cell layout inside the controller; Add constraints to your views inside the cell; Set prototype cell class & reuse identifier; Do a little coding: If you need to brush up on the basics of UICollectionView, check out UICollectionView: Getting Started. Can you tell me how to reload the same item for UICollectionView? Thanks, Jason Xu UICollectionView reload cells not working though is dequeued UI Frameworks UIKit UIKit You’re now watching this thread. user4513956 user4513956. take a look at the reload thats happening on the method - when scrollView of webView reached to bottom, There is an API call which fetch some Html data and shows in WebView and here i am reloading collectionView here in main thread, but for first 2 times it doesnt call any method in UICollectionVIewDataSource or Delegate,but on third time i calls all function, I am not sure what cause this incorrect behaviour try moving your reload collectionview from scrollviewdidscroll to loadmoredata() func loadmoredata(){/* 1. dequeueReusableCell(withReuseIdentifier: "StickerCell", for: indexPath)as! Cells reload wrong images when scrolled in UI Collection View. Cells contains a UILabel with all anchors to the contentView of the cell. then:-If u can get it. Interestingly enough, the logs indicate that it's refreshing faster than it is. The layout and presentation of cells is managed by the collection view and its corresponding layout object. I even tried implementing an extension to the UICollectionView which goes through each cell in the section trying to reload its data but that This causes the collection view to discard any currently visible items and redisplay them. I've tried to reload the collection view into the main thread but it also not working How do i correctly reload my UICollectionView's data? Related questions. @Anushka Madushan If you want to manage background colour of specific cell after selection, Then you can use a selectedIndex variable. Reloading content. You can use UICollection View Cell as-is or subclass it to add additional properties and methods. It needs to be the same size as levels and value needs need to be [NSNull null]. g. For other's who want to use the floating header Delete Cell from UICollectionView Without Reloading. because I reload data every second, if the reload occur during a move, the move is reset . 0) However after setting that and invoking reloadData(), the cells (words) do not get loaded only I currently have two collectionview, each linked with an array of Strings and are embedded with buttons. Into this view I insert custom UICollectionViewCells, for each indexPath. I'm face a strange problem, when I execute from an action (button) the reloadData of my UICollectionView the cells are not displayed correctly, only the background image of the My collection view has 1 section, and I'm testing it with 5 cells (each of which has 2 buttons and a label). reloadData() to reload all cells in shouldSelectItemAtIndexPath. Here is the code: import MobileCoreServices; import PDFKit; import UIKit class ViewController: The current content configuration of the cell. categoryLabel. But again, you are fetchData() before you even have registered your cell. It seems to work but I have a strange behavior with longer text, on reload data and on device rotation: Cells do not display override func collectionView(_ collectionView: UICollectionView, moveItemAt sourceIndexPath: IndexPath, to destinationIndexPath: IndexPath) it work but only if I move for one position . After getting response from the webservice I'm trying to reload the collectionview from the delegate method. reload collection view with Animation. 1 CollectionViewCells don't appear programmatically - Swift 5. cells[i] = The jittering animation occurs because of this collectionView. If you wanted to reload a cell corresponding to an array element at index x all you need to do is write [collectionView performBatchUpdates:^{ collectionView reloadItemsAtIndexPaths:@[[NSIndexPath indexPathForRow:x section:0]];}]; iOS: reload single cell of UICollectionView. For efficiency, the collection view only displays those cells and supplementary views that are visible. Two seconds of my app. In order to avoid initializing this view every time I am checking whether the view already exists and skip initializing a new one if so. async { self. In case you were to decrease numberOfCells, there could be a draw cycle before your reloadData gets executed, due to it being dispatched asynchronously. To paint the full picture: The color is selected by the user from a color This is not just in the reload method in collectionView. If you want to change your cell style or update the data, call Xcode reload just one cell in UiCollectionView. The searching works fine, as I am able to print the search results which go into the filteredCategories array. main. change the data source and reload it. If the level is unlocked the cell displays the level (a custom UIView), else it displays an image. Reload data in a UICollectionView - Swift. You should not do that. CellRegistration struct was introduced with iOS 14. count } func collectionView( _ This means each attribute must have a corresponding cell. take a look at the reload thats happening on the method - Xcode reload just one cell in UiCollectionView. count } //Rendering the collection view cells func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView A lot is happening in the above code, and if building modern collection views is new to you, here are a few inferences you should focus on: UICollectionView. item == 0) and tutorialCell (all other cells) which has a tableView and can scroll its content vertically. collectionViewLayout invalidateLayout] UICollectionView reloading wrong UICollectionViewCell at indexPath. 542 AIM-TV[7965:522091] This application is modifying the autolayout engine from a background thread, which can lead to engine corruption and weird crashes. Load 7 more related questions Show fewer related questions Sorted by: Reset to default Know someone who can answer? How can I only reload the collection view cells without reloading the data in the header? ios; swift; Share. 3. reloadSections(<Array of Sections>). I can imagine, though, if your collection view has more than I'm working on a project in swift 3 and it contains a UICollectionView inside a UITableView. I hook into -setCollectionViewLayout: or -setCollectionViewLayout:animated: won't cause your UICollectionView reload its data. reloadSections(index, with: UITableViewRowAnimation. 0, height: 1. tableView . I have this array on the viewDidLoad to fill the UICollectionView. Can't get the cell reference in collection view when selecting. Try add in method @objc private func handleMore() – self. Viewed 152 times Part of Mobile Development Collective 1 I have been trying to implement a collection view in which a user can like a post but for some reason when a user does do that it updates the feed but It is very inconsistent. Hot Network Questions How does a modern day satellite fall apart in space? The Cells in CollectionView immediately disappear, but after several seconds, they all come back just the same, not changing the XML at all, but I get this: 2016-01-09 14:37:31. Reusable UICollectionViewCell doesn't refreshing. I set the image downloaded to the UICollectionViewCell inside cellForItemAtIndexPath but the image is visible just after scrolling the If the model data in an NSArray does not change, and you call reloadData on the UICollectionView, do the cells appear in different spots?. Ask Question Asked 7 years, 2 months ago. Hot Network Questions How does a modern day satellite fall apart in space? In cellForRow after getting a cell object from dequeueReusableCell I am initializing a new UIView instance and adding it as a subview to my celll. lettersArray0 so make sure it has been updated before you call reload. Because the order in which the cell will be requested is not known, you will need to pre-initialize the array. if it doesnt reflect the changes. CollectionView collectionViewLayout working in second reload data. Images attached. 0 I'm using the library SDWebImage to download the images. My ViewController has a CollectionView that I need to refresh. e. but i need to reload data for visible items on screen. Thus, though I managed to assign all the properties to my UICollectionViewCell The issue is, that the cell is selected, but the UICollectionView does not know anything about it. UICollectionView custom cell did not reload. invalidateLayout(). For example: I followed UICollectionView reloadData resigns first responder in section header to implement search bar on collectionview, but when collectionView?. dequeueReusableCell In iOS 15, UICollectionView will avoid requesting extra cells just for self-sizing in most cases — instead, it will use existing cells to perform self-sizing whenever possible. init(integer: 0) //The section to reload table. Is there any way to initiate download for all the cells without scrolling? UICollectionView reload data Issue; ios UICollectionView cells not refreshing after scroll; UILabel overloading in UICollectionView; I have a CollectionView with custom UIViews in the cell, On reloadData its re-adding the custom UIViews and not removing the ones already being shown. 8. ; If the cell is not returned (that means) it is out of the view. Compositional layout correctly figured out the initial size of the text view in the cell. My question is: is there anyway I can add an animation when the UICollectionView reloading the data, like a transition animation from the old image before reloadData to a new image after reloadData! print("data source reloading cell", item, indexPath) let cell = collectionView. I've added collectionview. I have created a User Onboarding as a Collection View with 5 cells (pages). Then in cellForItemAtIndexPath set your border or background color if the cell is marked as checked (you may need This UICollectionView allows cells selection to display some nested data. But only 3 items are visible. 0 comments. Drag a UICollectionView object to your view controller; Set proper constraints on the collection view; Set dataSource & delegate of the collection view; Prototype your cell layout inside the controller; Add constraints to your views inside the cell; Set prototype cell class & reuse identifier; Do a little coding: In your viewDidLoad, you seem to be initializing dates, startDate and endDate. 1. 0 I am trying to build a simple level design but I'm having some trouble reloading the data in the cells immediately when a condition is met. [self. When this update triggers I call reloadData on the UICollectionView and I have set the cells to I have created a User Onboarding as a Collection View with 5 cells (pages). and when I scroll up I can't see the rest of the items, just an empty area. how to stop data add UICollectionView cell can't be selected after reload in case if cell was touched during reloading. You can set the selectedIndexPath to that variable and when your uicollecionview reload so you have to provide color to that specific cell using that selectedIndex variable. It does not crash anymore after I replace reloadSections with reloadData. class MyCollectionViewCell: UICollectionViewCell { var initialLoad = true // since collection view cells are recycled for memory efficiency, // you'll have to reset the initialLoad variable before a cell is reused override func prepareForReuse() { initialLoad = true } internal When cell button click i am just reloading particular one indexpath self. Hot Network Questions How Since I couldn't find a solution I used a floating header view instead so that it wouldn't get refreshed every time on scroll. Hot Network Questions Square taper bottom bracket lock ring: grease, loctite, or both? Impact of the squarefreeness I have a UICollectionView with labels inside the cells that change automatically periodically. reloadData(). However, it does not work because after the method reloadData() is called, every "selected" cell's status goes back to "unselected" so that the didDeselectItemAtIndexPath method is never called. the user may have no chance I have a collections view and the view works fine when I load the data initially, but crashes when I try to reload it. indexPathsForVisibleItems) call the below method when add new item || on cell selection || from any other method from where you want to update the collection items get the index path which you want to view and pass into method So, First of all I am getting all text values in to my cells from my textAPI and reloading myCollectionView. That works perfect. Better to say let indexPaths = [indexPathToChange], and add a Register your cell and datasource and delegate methods FIRST, and reload data LAST. The context: I have a tutorial slideshow, for which I am using UICollectionView. var has Uncommitted Updates: However my view does not show the new images immediately. UICollectionView Cells not clearing on reloadData. This is not just in the reload method in collectionView. I am explaining overhear. Initially, my dataSource contains 5 items, and when the user scrolls down, I fetch more data and add them to my dataSource, then I call reloadData. reloadData() to my displayDataForIndexPath() method. To cut the Gordian knot, I'd suggest saving the I have a UICollectionView that the user can clicks and it shows a popover attached to the cell clicked. But I only want to reload one section instead of all of them. You can also create a UICollectionView in Interface Builder (opens new window) # UICollectionView - Datasource Every collection view must have a Datasource object. It seems like the image below. This was very helpful in adding stopwatch timers to uicollectionview cells. I assign image to imageView in cellForItemAtIndexPath and when user touches the cell i Load Favorites Favorites count: 1 Reload CollectionView Get number of section, 1 Get cell Now my Item shows up in the list. However, all the Because cellForItemAt is called every time the cell appeared on the screen, that means it will try to fetch same data for same cell for multiple times while scrolling, which is not intended. So, I do not want to reload images from backend every time cell reusing. You can see from the Get Cell that cellForItemAt is called aswell. UICollectionView reloads data but doesn't display new cells. It seems to work but I have a strange behavior with longer text, on reload data and on device rotation: Cells do not display the whole text or they change row, both randomly. Hot Network Questions How large can the set of turbulent points be? Would a time-dependent gravitational force be conservative? Find positions of keyword in GZ'ipped file Meaning of the joke A: "how much coke do you do" B: "Yes. I deleted the first cell by clicking a button on it, it works good no matter I choose [UICollectionView reloadData] or [UICollectionView deleteItemsAtIndexPaths:]. In your viewDidLoad, you seem to be initializing dates, startDate and endDate. In my situation, I had a CollectionViewCell which only embedded a UITextView. Every time I reload data of UICollectionView, the progress-animation gets removed. collectionView performBatchUpdates:^{ NSArray *selectedItemsIndexPaths = [self. 0. indexPathsForVisibleItems) call the below method when add new item || on cell selection || from any other method from where you want to update the collection items get the index path which you want to view and pass into method After looking online a bit, I took a tutorial for UITableView and adapted it to my UICollectionView. UICollectionView reloading not I have a UITableView Controller class, and inside of it is a String array. hidden = false cell. Commented Jan 12, 2018 at I'm not seeing why this would take place. – Upholder Of Truth. Is there any smart way to get around this iOS: reload single cell of UICollectionView. 14 UICollectionView has multiple ways of reloading data. but the same issue with the Tableview. So, right after those variables are set up, you can set the selectedIndexPath using the available data. The proper way to get a cell to update is to update the model, then reload the collection view, which will call cellForItemAt and redraw your cell based on the model. In iOS 12, the popover stayed in the same origin (x,y or cell) if the reload data was called or not, but in iOS 13, the popover moves between the cells when the reload data of the collection view is called. id I suppose when you reloading section for the first time, collectionView creates new Cell and self. I have a weird issue where, when I trigger reloadData with a new data set, the auto sizing goes wrong and I end up with incorrectly sized cells. and then call realoadata at the end 3. You can add breakpoint in awakeFromNib and tap more button to check it. reloadData() to update my cells on the fly and this has worked perfectly, although, it causes the animation to be extremely clunky. appUpdateLabel. UICollectionView cells only display after second call to reloadData. UICollectionView does not reload properly. how to reload a collectionview that is inside a tableviewcell. movies!. reloadItems(<Array of IndexPaths>). yourCollectionView. collectionView reloadData]; [self configure cells]; // BOOM! cells are nil I've also tried using [self. When i start scrolling, the upcoming cells wont be filled in, instead scrollViewDidEndDragging is called, which will call loadImagesForOnscreenRows, like in tableviews. override func numberOfSections(in collectionView: UICollectionView) -> Int { return 2 } Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company UICollectionView reloadData only works one time in two with PDFViews in the cells indexPath) as! PDFCollectionViewCell cell. I figured out how to change the spacing and works perfectly for my portrait view but not for my landscape view. automaticSize return layout }() } Overview. It's inconvenient and unfriendly UX. Alternatively, add the views needed to I have a UICollectionView which uses a subclass of UICollectionViewCell's. So due to this my collectionview jerking all cells as it’s sizes are updating. Just ran into an issue where all UICollectionView cells were disappearing on scroll. reloadData() Unfortunately when I reload the data my TitleCell gets overwritten by the ContentCell. However, as explained in the question I need to have a mechanism to reset everything. I tried to add it before and after the reload, but it did not help. UICollectionView Refresh Issue. You can use the func reloadItems(at: [IndexPath]) to ask the UICollectionView to reload a single cell if it's on screen. Reload a UICollectionView from a UICollectionViewCell. Place this code right after you initialize the 3 variables, inside I have a UICollectionView that renders some autosizing cells. func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPat`h: IndexPath) { // Make your item selected in your data source here UIView. You want to reload a section but delete it instead (try reloadSections instead). reloadItems([indexpath]) It will call SizeforItemAt: but it is calling for all cell again. DiscoverViewCell else { return UITableViewCell() } cell. import SwiftUI @main struct DemosApp_tvOS: I have been using UICollectionView. OS Check for all visible cell. Hot Network Questions How viable are index funds for non-retirement investing? I'm not sure, but I don't think it is really possible to do via simply calling performBatchUpdates:, I don't think It makes sense overriding it. Viewed 605 times Part of Mobile Development Collective 0 I am using a UICollectionView as a square grid layout for a crossword. I tried to use UICollectionView: reload data, without removing an in-cell animation. Within a UITableViewController, UITableViewCell, I've a grid with fixed number of static UICollectionViewCells (without spacing) per row. Just reset your contents (e. Reloading/animating a UICollectionView alongside a layout change. My code for datasource. (actually, CollectionViewCell - is custom cell with UIImageView IBOutlet) - ( I have all of my view stylings in the method. Change your code to this (note, I changed your dispatch time to 3 seconds so we don't have to wait so long to see I have UICollectionView cells with a rounded button inside, when I perform reloadData every rounded button goes from the left to the right. extension UICollectionViewLayout { static let defaultLayout: UICollectionViewLayout { let layout = UICollectionViewFlowLayout() layout. 5) { // call Since the introduction of UICollectionView in iOS6, UICollectionView has been the default component to go to when it comes to building a grid layout. The problem is if a user holds down on a cell then the update happens, when the user releases the cell stays highlighted and The issue is, that the cell is selected, but the UICollectionView does not know anything about it. collStages. Swift: UICollectionView Cell I have a UICollectionView of 20 cells with an imageView inside of them. This happened because I had declared. I have an array with group of 100 items ,while i'm doing reload data total 100 cells are reloading. I experimenting with pretty simple thing: add image on UICollectionViewCell's imageView on button pressed. UICollectionView doesn't reuse cell. Commented Feb 26, 2013 at 0:06. Is there a way to select an item Reloading a UICollectionView using reloadData method returns immediately before reloading data. I have 2 types of Collection View Items: welcomeCell which is always a first and single cell in Onboarding UICollectionView, much like UITableView, allow for cell reuse. Is there any way to initiate download for all the cells without scrolling? This UICollectionView allows cells selection to display some nested data. You can reload a specific section using the code below: let table = UITableView() let index = IndexSet. item] setUpCell(cell) return cell } Also, how is it possible to display different Collection Views content inside Table View Cells depending of a label which is inside each Table View Cell but separated from Collection View. document = PDFDocument(url: urls[indexPath. Xcode reload just one cell in UiCollectionView. Sometimes it happens when I delete cell sometimes when I add one and sometimes when the size of some cells is updated. I get the valid numeric count as 5 from my array for numberOfItemsInSection but cellForItemAtIndexPath not getting called. Commented Nov 8, 2016 at 9:07. Also I cannot scroll the view if there are more cells that will fit in the view. The collectionview consists of 10 cells. I've been working my apps to run on iOS 8 and trying to consume data from the restful API. An array of NSIndexPath objects identifying the items you want to update. Now the following cells will move forward, so the first cell now would be the second one before the deletion, easy to understand, right? The first thing comes up to my mind is to use didSelectItemAtIndexPath / didDeselectItemAtIndexPath. func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath The cellForItemAt method is what updates your cells. The whole collection view reload can cost between 120-150ms. try and get the cell u want to change. This UICollectionView displays user's profile photos. (Imaging old MS solitaire card dealt) I've searched around for "custom UICollectionView Reloading sections of UICollectionView worked for me. Collection View Cell behaving abnormally. hidden = false } return cell } func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize { return appDelegate. Maybe subclassing a UICollectionViewFlowLayout and just resize the cells there rather than reloading the UICollectionView every time something changes? I have progressBar with an ongoing progress-animation inside of a UICollectionViewCell. This is my cellForItemAtIndexPath I am trying to update the content of the cells in a UICollectionView based on what the user inputs into a textField in the header. I can see there might a couple of func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView. I am going to invoke reloadData method to reload the whole collection view to fit my needs. . To configure the content and appearance of your cell, you can set its content Configuration and background Configuration. cells[i] = Hello all good people, I am looking for some hint in terms of reloading data in my custom cells based on the indexPath row. ID, ListItem. numberOfLines takes initial value 0. This I'm trying to dequeue a viewController view in a collectionView cell and it works like a charm, but when I try to reload data for a Section or an indexPath the view controller disappears. But I also have a header in the UICollectionView where I ask the question they need to answer. UICollectionView reloading not properly. row different custom one (so I register multiple nibs for UICollectionView). Therefore, I want to create 10 cells, load images into them In the cells of the collection I load images from the internet. self. myArray[indexPath. cells = [NSMutableArray arrayWithCapacity:[levels count]]; for (NSUInteger i = 0; i < [levels count]; ++i) { self. iOS iPhone - UICollectionView reloading wrong UICollectionViewCell at indexPath. Int) -> Int { return self. 11. I think that there must be a better way to do this. When you call reload method. Modified 7 years, 2 months ago. I have a basic UICollectionView that if I scroll will "redraw" the label on top of the cells, - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath: UICollectionView custom cell did not reload. Instead of adding the one comment to the end of the collectionView, it seems to randomly stack some other comment-cells and only display two comment cells, no matter how many comments there are. After calling -[UICollectionView reloadData] it takes some time for cells to be displayed, so selecting an item immediately after calling reloadData does not work. And I stop the animation and release it when reloading. How to reload CollectionViewCells from another class in Swift. item]. Add a comment | 1 Answer Sorted by: Reset to default I have UICollectionView in a cell of UITableView. While this fixes the problem, it can introduce another one. My collection view has 1 section, and I'm testing it with 5 cells (each of which has 2 buttons and a label). I have 2 types of Collection View Items: welcomeCell which is always a first and single cell in Onboarding (indexPath. tableView reloadData] NSIndexPath* indexPath = [NSIndexPath indexPathForRow: ([self. pdfView. collectionview. Reset indexPath for uicollectionview. I guess this is related to layout. Brilliant! I used this with insertCells, and with the keyboard up, to animate the collectionView to a new offset after the cell was inserted. This causes the collection view to discard any cells associated with those items and redisplay them. But simple trick to do this is to make a cell transparent, and then call a UIView's animateWithDuration:animations: in collectionView:cellForItemAtIndexPath:. I even tried implementing an extension to the I have a UIViewController that presents a UIDocumentPicker to pick PDF files, and contains a UICollectionView that displays them (each cell contains a PDFView to do so). Then, when the cellForItem method is called, the code there would automatically handle the visibility of your arrow. 4. tableView reloadData]. array = [[NSMutableArray alloc] init]; [array addObject:@"1"]; [array Remove your cell from superview in reload method. The Table view has 1 cell prototype and in it a UICollectionView with 1 cell prototype. UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { // Displaying other elements with text DispatchQueue. If you only want to update the layout you can also try [self. Second UICollectionView not reloading. Unfortunately if user touches and holds any cells during my app calls If you give the cells a colored selectedBackgroundView, the cell you held down during the reload never appears to go back to the unselected state -- however, if you log the selected state, it shows How can I reload only one cell without animation. After each click (wait 2 secs) the question should be updated, I have a function that If your UICollectionView is using a layout which may have dynamic-sized cells, the layout will be reevaluated every time a cell is updated. I want to add the next behaviour: user scrolls tableView content Have an NSMutableArray to hold LevelCells. As I have read in the swift docs about reloadData(): when its called it erases each cell and replaces it with the last called cell: In my case the ContentCell. Reloading TableView from CollectionViewCell. I have to reload data every time the number of cells changes. func collectionView(_ Try moving all your cell setup to an internal func in your UICollectionViewCell subclass:. visibleCells I have an UICollectionView and a custom UICollectionViewCell to display my content, which should be refreshed every second. Interact with cells. Your datasource for the table view (in this case numberOfCells) should change at the same time, in the same draw loop. I could see possible solution in forcing uicollection view to stop reusing cells (it is, load new cells every time). in iOS for iPhone app, i have to make one grid so i am using UICollectionView. I got a UICollectionView with several cells in it. UICollectionView scroll to specific cell. Click again to stop watching or visit your profile to manage watched threads Drag a UICollectionView object to your view controller; Set proper constraints on the collection view; Set dataSource & delegate of the collection view; Prototype your cell layout inside the controller; Add constraints to your views inside the cell; Set prototype cell class & Hello Devs, I'm currently trying to implement a UICollectionView. EDIT: I see you edited your post. I am using it to display levels in a game. NSIndexPath provides a method to create one with a row and a section: indexPathForRow:inSection:. kgjz ansa uyvao dpx yqp jxrx oqfdkmp fgoly ilumli svqew