I am trying to have the content in a uicollectionviewcell grow bigger when it scroll moving in one direction. i initially set the size of the cell to the largest size i want, then the content inside the cell is half in terms of the size. the content is an uiimageview.
So I have a custom UICollectionViewFlowLayout in which I subclassed the layoutAttributesForElementsInRect to make the uiimageview in the cells grow bigger when it is moving in one direction. i also have shouldInvalidateLayoutForBoundsChange to return YES
Everything works perfectly when i scroll, the imageview will grow larger. However if i select a cell to push to a new viewcontroller, and then when i click the back button to come back to this uicolletionview, the enlarged uiimageview in severals cells are showing in the original size. They can only go back to the correct enlarged size if i scroll again, why is that? and how can i make it keep its enlarged size after getting pushed?
i tried invalidatelayout but it will just refresh the layoutattributes with correct enlarged size of the content, but the view is just not updated eventhough the size is already enlarged.
thanks
I had a similar issue when designing cv cells and would gess the issue is with when the subviews get calls to update their size, which might not happen when the view refreshes.
Instead of resizing content in the cell, you might want to dynamically size the cells themselves and have the content automatically adjust to that size. Calling [mycollection invalidateLayout] then should be all you need, maybe not even that.
The method is
collectionView:layout:sizeForItemAtIndexPath:
which you declare in your UICollectionViewFlowLayout.h
If you then run into trouble where subviews do not resize with cell size, related problems can arise from constraints/autolayout etc of the subviews.
Related
I have a horizontal-scrolling UICollectionView which is nested in a UIView that is centred and occupies 80% of the screen width.
I want the UICollectionView to be visible screen edge-to-edge rather than constrained to the super UIView bounds.
I have set the following which shows the UICollectionView across the screen width:
collectionView.clipToBounds = NO
...but when dragging the collectionView, it hides cells when they are completely outside of the super UIView bounds even though they are partially visible on the screen, which leads to a weird flickering of blank space/cell.
Ideally, I'd like a way to prevent the hiding of the cells completely out of bounds. Is there a way to do this?
The UICollectionView has a maximum size of 3 cells, so I'm not particularly worried about any performance implications of having all cells visible all the time.
The only way I found is to enlarge the frame of the collection view (and its superview in your case) and add contentInset's to it. You might also want to update scrollIndicatorInsets.
I need to show three/ four UI buttons and levels, two image views in a custom cell but there is a condition on the basis of that I need to hide an imageView and when it will be hidden, I need to decrease tableview size and buttons which are below of that image view that will move upward.
For that I am giving required conditions in
heightForRowAtIndexPath
and returning cells height accordingly and in tableview
CellForRowAtIndexPath
method I am hiding imageView and setting buttons positions which are below of that imageView.
The problem is that:
1) TableView is not scrolling smoothly
2) Initially at the time of scrolling down everything is working but when I
move upward then image is resizing and changing its shape. To solve that I have used AutoLayout but still it is not working.
I need your expert advice.
Thanks in advance.
I have a UITableView in my app where each UITableViewCell has a custom view added to its contentView. Now, each such custom view can come at any height and I verified that tableView:heightForRowAtIndexPath: returns the correct value. The thing is it used to work just fine prior to iOS7. In iOS7 it cuts off every cell's content at the exact same spot, about 40-50 points from the top. I can see using the table view's separator that each cell has the correct height, so it isn't a matter of the cell going beyond its bounds and being clipped. It is clipped while being contained fully inside the cell's bounds.
Anyone has any idea what is the cause of this issue and how to solve it?
The scrollView, which is there with UITableView dose not change it's size.
So I have a UITableView, where Cells are added by the User. Right after adding these cells, I'm calling
[self.tableView reloadData];
Now the tableView shows the new cells added by the User. fine. But, if the tableView get's larger, if it's too big to show everything in the view, it doesen't change the size of my scrollView. I have no scrollView in the view, aside from the "normal" scrollView, which comes with the UITableView. So I can't scroll to the last row, because the scrollView is "too small".
Is there anything I forgot? I'm thinking of something like
[self.tableView.scrollView reload];
I'm using the same concept in another class: The user is able to add cells and they're shown. But in the other class the scrollView "resizes" correctly.
I assume that you have table inside a scrollview. You need to change content size of scrollview after adding cells. Height of content size should change according to content in scrollview so that you can scroll through whole content.
Updated answer:
I think your tableview's frame is larger. It is crossing window's bounds. Try minimizing tableview's height.
I have a UITableView which loads the icons for my other apps.
They look fine at a good 57x57 automatic size in a cell which is 70px height.
When I click on a cell, the image suddenly scales up to 70x70 and I have no idea how to stop it.
Any ideas?
Thanks,
Ashley
So the way I understand it is you are adding a UIImageView as a subview to a cellview.
The way I do this that works great even where the image is smaller than the cells row hieght is add the UIImageView in cellForRowAtIndexPath then set the frame to something that fits in the cell and is the image size.
You might be building the custom cells in the UI Builder, but explicitly setting the frame of the image view to CGRectMake(imageview.frame.bounds.x,imageview.frame.bounds.y,57,57) and setting the autoresize property for vertical and horizontal to none should stop it from scaling up.