I have a collection view. I need to scroll only cell4, cell5, cell 6 so on. First two cells are remain same. Is is possible using only UICollectionview. How to achieve this.
FYI: the height of the cell is more than the screen height.
One of options would be to subclass UICollectionViewLayout and update frames in attributes of first three cells every time when scroll offset changes. So the cells would look static.
Related
The problem I am facing is that when I send a data to UITableView then I send a command to scroll the table to bottom. If cell heights are constant then my scrollToLastCell takes to last cell but with dynamic cell heights it doesn't always takes to last cell.
I want to know is there any way when I can be sure that all cells of my tableView is finished resizing and then I trigger scroll to bottom?
In the Docs Apple states
Important
If your table view includes self-sizing cells, headers, or footers,
you must provide estimated heights for those items.
https://developer.apple.com/documentation/uikit/views_and_controls/table_views/estimating_the_height_of_a_table_s_scrolling_area
Given that, I'd suggest you to go ahead and use tableView(_:estimatedHeightForRowAt:) method
I am working with collectionview inside tableviewcell in Swift 4. I get the content from server which is all dynamic. I have to show different types of collectionview behaviours.
For example, in the first tableview row should be collectionviewcell with screenwidth and scrollable. In the second row, collectionview with 3 sections and each section has different content different number of items.
Here I got stuck I am unable to show 3 sections one below other it is showing besides horizontally. I have calculated collectionview flow layout size.
Also in last row I have collectonviewcell with scrollable content,here when i scoll the content is repeating from bottom row or top row. I want the smoth scrolling and to stop repeating the content.
I am new to Swift. Can anybody help me out of this . Thanks in advance.
The smooth way is to create tableview with its cell xib and inside its cell add collection view and create another xib for collection view cell. This method is helpful when accessing collection view for different tableview cell. Rather using without loading Xib's may mixup your code.
You have to set tableview cell height as UITableViewAutomaticDimension. This will handle your cell height as per your dynamic content.
For each tableview cell you have to set collection view's property by using cell's index path as per your requirement.
I'm struggling with wired kind of problem. I have UITableView with one cell. This cell is only holding containerView with childViewController (second tableView). My problem is that, first tableView(parent) must have UITableViewAutomaticDimension row height but it doesn't work (It dosen't know correct size of that cell with second tableView).
How to get correct size of second tableView) ?
Second tableView (inside Cell) have scrollingEnabled turned off (tableView.scrollEnabled = false), first tableView must have correct size of second tableView in order to provide correct scrolling experience.
Since a UITableView inherits from UIScrollView you can use the contentSize property to get this information. This is how the scrollbar works on the side.
I have done a similar thing before (long ago), so the following is somewhat hazy/ irrelevant/ unessecary. There might be some gotchas with unknown/unrendered cell heights in the embedded tableview. I rememeber having to set the tableview height to a large number (forcing all cells to render) fetching the contentSize then resetting the tableview height to the contentSize.height.
Are you shure you really need second table view? If you have just one cell probably you don't need it. I recommend you to calculate table view height as the summ of it's cells heights. If cells of embedded table view have constant height it could be simple. In other case you also could calculate cells height.
Consider the following:
I have a UICollectionView with a size of 400x400. This UICollectionView has 5 UICollectionViewCells which also have a size of 400x400.
Clip to bounds is set to false so that my UICollectionViewCells will be visible (this does not work, I can only see 1). I want this so I can use paging. When I start scrolling there are 2 cells, but when the scrolling snaps, the previous cell disappears and I can only see 1 cell.
I use dequeueReusableCellWithReuseIdentifier to retrieve cells to fill the collectionview. Can this be part of the problem?
How can I display the UICollectViewCells that are out of the collection view's frame?
You can't. What you describe for a problem is actually a feature of UICollectionView and UITableView. They reuse the cells that are not visible for performance and memory reasons. You might think of another approach like UICollectionView with custom layout if that would be possible for your requirement or directly use UIScrollView with paging and you rearrange all the views while is scrolling.
I have tried looking for an answer to this question but so far I haven't got any luck.
Context
I have a UITableView inside a standard UIViewController (NOT a UITableViewController..). I have subclassed UITableViewCell and all the cells in the tableview are from the same class.
Requirement
I would like to find an efficient way to resize the cells based on the scrolling of the tableview. For example, when the cell is at the bottom of the visible list, the height is X. When the cell moves up on the screen, its height should proportionally increase to 2X.
Additional Info
I am close to just ditch the UITableView way and start making my own control that would implement such a feat by subclassing a UIScrollView. However, I would like to see if it is possible before going this path. I did see some very interesting SO posts but nothing that would put me on the right path.
Any hint or help would be highly appreciated.
You would need to respond to the scroll view delegate method scrollViewDidScroll: and implement it to record the cell at the top of the table view and reload the table view. Then your table view delegate method tableView:heightForRowAtIndexPath: sets the cell height by the relationship between the index path and the top cell index path.
Your main issue is performance while reloading the table view all the time.
If you wanted to roll your own solution it would be along the lines of the above description anyway, but you would be able to be more efficient than the table view as the table view will call the tableView:heightForRowAtIndexPath: method once for every row for every reload in order to calculate the total height of the table content.