How to make UITableViewCell display fullscreen (allow paging)? - ios

I have a custom UITableView - Scroll, Paging Enable. Because each of my cell has one background image, I want each time I scroll up or down it will display each image as full screen. I try to make my UITableViewCell to be full screen (stretch its height as big as the tableview).
However, I've got a problem: when I scroll(paging), the cell doesn't display as full screen. It contains a small part of the next cell. Then the part of next cell increase bigger and bigger each time I scroll(paging) down.
I didn't see any Auto Layout Option for UITableViewCell, cannot add constraint to the prototype cell. Would you please suggest me the way to do it? Thank you very much.

i just add this two lines of code and it works for me
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return tableView.frame.size.height;
}

// ***** The following SWIFT function expands the cell image view to full screen (frame.size.height), adding to M.Salah's reply above.
override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return tableView.frame.size.height;
}

Related

UITableView inside a UITableViewCell in iOS

Hello I want to create a UITableviewCell like this.
There can be 1 or more attached documents.How can I show attached documents if there are more than 1 documents.
Can I use a A UITableview inside the UITableViewCell? If so how? What is the best way that I can achieve this?
Please help me.
Thanks
A vertical scrolling inside a UITableViewCell would be kind of strange and complicated because you can also scroll in the normal table view. Wouldn´t it be a better solution for you to set the height of the cell depending on the number of attached items. One pseudo example:
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return cell.attachedItems.count * 50
}
Then a cell with more attached items would be bigger and you could keep the normal table view scrolling flow.

UITableViewCell height from initial size to full screen

how i can swipe down (scroll) one cell from my tableviewcell (static cells) and make this cell fullscreen?
I know how make the cell full height:
override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return tableView.frame.size.height;
}
But how i can start this cell with a fixed height and after swipe down (scroll) the cell, make the cell fullscreen?
Thank you
The way I do this sort of thing is actually to treat this as a master-detail interface. The gesture does not really expand the cell; it does a "push" of another view controller containing the full-screen version. And it does it with a custom transition animation, so that it looks like the cell is expanding to form the full-screen version.
And the same thing when returning (popping), in reverse.
This is an example; it isn't 100% identical to what you're doing, but it shows how the push-plus-custom-animation can give the sort of effect you're after:
You can also monitor frame changes in your cell class and expand when the cell is pressed, (not scroll if that's what you really want) and by monitoring frame change you can expand the cells height. Let me know if you want more information because this is on selection, not on scroll.

UITableView with dynamic cell heights jumping when scrolling up after reloading cell

I have a table view with the potential for each cell to have its own height, thus isn't suitable to use rowHeight. Instead, right now I'm using let indexSet = NSIndexSet(index: 10), and self.tableView.estimatedRowHeight = 75. This means that it calls the sizeThatFits function on the cell, to determine its' height. This all works well.
The problem is then when you reload a cell that's onscreen. Scrolling down to show cell 10, for example, then reloading cell 10, works fine. But when you begin to scroll back up, past the cells you've already seen, it reverts to the estimatedRowHeight for each cell, completely disregarding sizeThatFits, and so jumps around as you scroll. It'd be impossible for me to give an accurate or 'good enough' estimatedRowHeight so that this jumping wouldn't be noticeable, as my cells will be able to display either a line of text, or a full image - a big difference in size.
I've shown this effect here:
https://vid.me/edgW
I've made many different attempts at this, using a mixture of heightForRowAtIndexPath, estimatedHeightForRowAtIndexPath.. etc.. I've tried various pieces of advice on StackOverflow. Nothing seems to work.
I've attached a very simple sample project, where you can try it for yourself:
https://www.dropbox.com/s/8f1rvkx9k23q6c1/tableviewtest.zip?dl=0
Run the project.
Scroll until cell 10 is in view.
Wait up to 5 seconds for the cell to reload (it becomes purple).
Scroll up.
Worth noting - this does not happen if the cell is not in view when it's reloaded. If it's either above or below the current scroll point, everything works as expected.
This behavior appears to be a bug, if for no other reason than it's no longer reproducible on iOS 9. I'm sure that's not much consolation.
The issue primarily derives from having an inaccurate estimate, like #NickCatib said. The best you can do on iOS 8 is to improve the estimation. A technique many have recommended is to cache heights in willDisplayCell and use them on subsequent calls to estimatedRowHeightAtIndexPath.
You might be able to mitigate the behavior by not doing anything to get UITableView to discard its caches, like by modifying the content in a cell directly using cellForRowAtIndexPath rather than using reloading if it's onscreen. However, that won't help if you actually need to change the height of the cell.
I'm afraid to say the bug can't be easily be fixed within a table view, as you don't have control over the layout. The bug can be more easily worked around in a subclass UICollectionViewFlowLayout by changing the contentOffsetAdjustment during invalidation, although that might not be terribly easy.
I had this issue too and used a solution from SO which I am unable to find right now. If I do, I will add the link. Here's the solution:
The issue is with table view not having the right estimate for height of rows. To fix it, cache the height initially in willDisplayCell and next time use that height.
Code
In viewDidLoad:
heightAtIndexPath = [NSMutableDictionary new];
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
NSNumber *height = #(cell.frame.size.height);
[heightAtIndexPath setObject:height forKey:indexPath];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return UITableViewAutomaticDimension;
}
- (CGFloat)tableView:(UITableView *)tableView estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath{
if([heightAtIndexPath objectForKey:indexPath]) {
return [[heightAtIndexPath objectForKey:indexPath] floatValue];
} else {
return UITableViewAutomaticDimension;
}
}
In iOS 13.5.1:
I have a tableView which contains 4 types of cells , all off them having different and dynamic heights.
I have followed the accepted solution here, but to solve jumping effect I need to add more when reloading table view:
From accepted answer I have added below code:
Declare this variable
var allCellHeights = [IndexPath : CGFloat]()
Then add 2 methods:
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
self.allCellHeights[indexPath] = cell.frame.size.height
}
func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
return self.allCellHeights[indexPath] ?? UITableView.automaticDimension
}
Now the extra code I have to add when reloading tableview:
let contentOffset = self.tableView.contentOffset
self.tableView.reloadData()
self.tableView.layoutIfNeeded()
self.tableView.setContentOffset(contentOffset, animated: false)
also check this answer : reloadData() of UITableView with Dynamic cell heights causes jumpy scrolling
Uh... this is kind of hard issue to deal with.
Let's take a look at facebook. They had this same issue with their timeline, and they ended up doing it in some kind of web view.
I had a similar issue with some kind of timeline, used automatic row height and had that issue. First thing to resolve it was to set estimatedHeight as close as possible to average cell height. That is pretty hard to deal with since you may have text (height 50) or images + text ( height 1500). Next thing to do with improving this was implementing estimatedHeight forIndexPath which basicly return different estimated height for different indexPaths.
After that there were a lot of other solutions but this was as closest as it can with variable heights (huge differences).
I was facing the same problem, my table works fine until the tableview reloads. So i found a solution, use only rowHeight not estimated height. Also if you have different height. So please provide the complete code so i will provide a solution. I have a cell which like instagram page. I am passing calculated height in heightforrow method which work fine. But estimated height not works fine in that situation. If you use below code, it works fine. Please try.
self.tableView.rowHeight = 75 //it will be your dynamic height
//self.tableView.estimatedRowHeight = 75
If you confuse to calculate the height for row for each cell, just post the sample i will provide the solution. If i can
Thanks

How to make fixed height cell on uitableview?

So I want to make timeline content like instagram, I'm using custom cell on my uitableview. My problem is I already set the cell height to 345 on the storyboard but I get cell table like below:
and here is my custom cell on storyboard:
How can I fix it, so I can get the result like on my storyboard?
The reason that you are having this issue is you have probably set your Custom tableview cell's row height to 345 but that is not set as custom while your UITableview's row height is less than 345. So, what you need to do is go to storyboard and select the Table(UITableview) and set its row height to the maximum possible row height.
Let's assume that you are going to have two different kind of row heights. One with 345 and another with 325. As 325<345, you set your tableview's row height to 345.
Now, select the custom tableview cell and make its row height as custom and set that to either 345 or 325. In your case, it will be 345.
It should be good now.
However, more appropriate way when you have different cell size would be to use the delegate method for row height specification.
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
if(indexPath.row==0){
return 345;
}
else if(indexPath.row==1){
return 325;
}
else{
return 300; //a default size if the cell index path is anything other than the 1st or second row.
}
}
Use this delegate method:
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return 345
}
In your UITableViewController subclass, set self.tableView.rowHeight = 345. Might be a bug with storyboard heights not being translated.
You can set Table View Cell height here.

How to make UITableView appear from bottom to top when scroll?

I'm looking just for general scenario.The idea is when app launches user can see only first cell of UITableView at the bottom of UIViewController. When user scrolls up full table appears and when scrolls down only first cell is displayed again. Something similar like keyboard in Facebook messenger app, but with tableView. For now I added tableView as subview to scrollView, but problem is tableView appears from top to bottom, and I'm looking for solution how to make this work upside down.. So, tableView have to appear from bottom to top of UIViewController.
My idea would be:
Give your UITableView the desired frame at viewDiDLoad (probably the height of 1 cell, at the bottom of your UIView)
Let your UIViewController implement UIScrollViewDelegate
At - (void)scrollViewDidScroll:(UIScrollView *)scrollView of UIScrollViewDelegate check which element is scrolling (if its your UITableView) and also check which direction user is scrolling
Change the frame of the UITableView as you wish, you will also have to come up with some logic to block further changing of the UITableView's frame (a BOOL would do good here I guess)
Not sure I understand your correctly but, maybe, this will be helpful
I believe you can try to add zero cell (or first section header view of your UITableView) with transparent background. So that your first cell will be placed on the bottom of screen and UITableView height will be equal to screen height.
In this case, you will have only one scrolling view (UITableView, in particularly). Following method can be used to perform expandable animation and scroll table to top to hide zero cell when user taps on first cell:
[UITableView scrollRectToVisible:animated:]
After that you can leave UITableView as it is and "constrict" your table whenever you need in the same way as it was expanded before.
I understand what you want to do.
In general, UITableView shows cells from top to bottom.
You can add transform in tableview:
tableView.transform = CGAffineTransform(scaleX: 1, y: -1)
Then your tableview will show the cells from bottom to top and you can scroll tableview from bottom to top.
But cells will be transformed as tableview, so you have to add same transform to cells also.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
var cell: UITableViewCell = tableView.dequeueReusableCell(withIdentifier: "cell")
**cell.transform = tableView.transform**
return cell
}
All done. Hope to helpful!

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