Hi I have an image array which consists of images with different sizes. I am going to display them in a Horizontal UICollectionView. And I need to show these images with same height , same padding (not the cell interim space, but the look of the image) and different widths.
Example:
Any help would be highly appreciated!
You need to implement this method , inside it generate your random width and pass it to the width parameter
func collectionView(_ collectionView: UICollectionView,
layout collectionViewLayout: UICollectionViewLayout,
sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width:<#variableWidth#>,height:<#sameHeight#>)
}
Well creating your custom collectionViewLayout is also an option. It will give you more flexibility but at the same time you have to do all the calculations yourself.
Looking at your case, it appears you can use a horizontal stack view embedded inside a scroll view. So in this approach you just need to add your views with different widths and set the stack view fill property to proportional. You can refer this link for more details.
Related
I'm using this library, CHTCollectionViewWaterfallLayout
(https://github.com/chiahsien/CHTCollectionViewWaterfallLayout) to try to replicate a feed that's similar to the Pinterest layout or the Imgur layout shown in the screenshot below. There's 2 columns and then each card has a variable height based on the height of the image it's showing.
What I'm having trouble with, is calculating the right width and height for sizeForItemAt, since I'm loading these images from URLs:
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
I believe I can store the width and height of each image, but then how do I calculate the height I'll have to add from the little section beneath the picture, where there is more text. Currently I've built these cards in SwiftUI which is great for dynamically fitting the text, but I don't know how to get the size. Do I need to build these cards in Swift, or is there a way for me to get the additional height I have to add to the images height, for the aspect ratio to come out correctly?
I'm using drag and drop to drag images from google onto a collection view. The images are all supposed to have equal widths. After I scroll a bit, some of the cells look like they have equal widths, but some images are too big.
The collectionView has a flow layout and horizontal scroll direction.
In the following gif, the images start out as if they may have the same width(I can't really tell). When I drag an image in, they resize, and you can immediately see that the two on the left no longer have the same width, the one image is huge, and the huge image has a smaller duplicate(there should only be one beach seal picture), but the dragged in image is missing(until I scroll back and forth). When I close and reopen, the widths look ~correct again(but the images are place sporadically, I'd like a nice compact layout). When I scroll up, the images become the wrong sizes again. (My search was for the word 'seals' if you're interested in duplicating)
This is my code for sizing the cells
var gallery = [(URL,Float)]()
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let width = cellWidth
let (_,ratio) = gallery[indexPath.item]
let height = Float(width) * ratio
return CGSize(width: Int(width), height: Int(height))
}
Update
I was able to stop the images from getting to big by setting Estimated Size to None in my storyboard. Now it appears that not every image is as wide as it is supposed to be(each image should have the same width). Also there's a lot of space between my cells which I don't want. There doesn't seem to be a pattern to how much space there is either.
Github
My full project on Github
I have spent a few day's now trying out things suggested on various SO posts but have not been able to figure this out. I'm probably looking right at the issue!
I am making a switch over from Android to iOS and seem to be having some trouble with autolayout. Specifically, getting the UICollectionView to resize to the height of its content. Each collection view can have a different cell size based on its content but the cell size will be the same for each item on a given row.
The UICollectionView is nested inside a UITableViewCell. The UITableViewCells appear to be resizing to its content height correctly and looking at the Debug View Hierarrchy the issue seems to be the UICollectionView.
I have created a mini demo and put it on this github (link below). I have thrown in a bunch of test data so the bottom part of the ViewController VC is a bit messy. The demo just illistrates how each row can have different content size. There can be several table rows of the same style.
NOTE: I had to add the following line to CategoryRowCell.swift in order for me to get the below screen shots. Without this line the UICollectionView height becomes 0!
...
collectionView.heightAnchor.constraint(equalToConstant: 250)
...
GitHub link
So here is what it looks like right now..
scrolled down
Notice the gaps at the top and bottom of the horizontal lists. Here is what i am expecting..
Here is part of the debug view hierarchy. You will see that the collection view already has top and bottom margins (good), but the red lines show the excess height being applied to the collection view. The green line indicates the height i am expecting. I am wanted the collection view to have a height of its content.
I think it would be better to do it the other way around, having the UICollectionView as the parent and UITableView as the child. Since the first is more flexible and customizable.
Anyway for your case I think you need to take a look at two things:
1- To have a better control of the cell size you can use this func for UICollectionView:
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: IndexPath) -> CGSize {
// The desired size based on the value at that row (the name for example)
if objects[indexPath.row].name == "some condition" {
return CGSize(width: 150, height: 50)
}
else {
return CGSize(width: UIScreen.main.bounds.width, height: 75)
}
}
2- The size inspector values for the UICollectionView and UITableView (you might have some extra spacing in one of them)
I got three collectionViews in my application. Now I finished it as far as I wanted it to complete. The only problem which I have for several days now are the constraints. I don't know how to explain it in words so I added two pictures of the problem to the question I hope it's understandable.
What I currently have:
What I want:
Use UICollectionViewDelegateFlowLayout delegate method to archive this.
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize
in this method, you can programmatically set size of cells. Give sizes according to your need of each collectionView.
Based on your screenshots, it looks like the collection view holding the column of white dots expands its width when the superview (the screen size) changes.
It also looks like you are using Flow Layout... when the view gets wider there is enough room for 2 cells on each row.
You should be able to fix that by either:
constraining the width of that collection view so it doesn't expand, or
using a custom Collection View Layout
I'd suggest trying a width constraint first - see if you can get the layout to look the way you want.
As a side note... using collection views may not be the best approach for what you're trying to do. UIStackView might be a better option (although, I don't know what else the interface will be doing, so maybe not).
I'm currently using a UICollectionView and a UICollectionViewFlowLayout and the following UICollectionViewCell:
However, a bug was raised recently that locks the UI and upon inspection the console kept spitting out the following continuously to the console.
Make a symbolic breakpoint at
UICollectionViewFlowLayoutBreakForInvalidSizes to catch this in the
debugger.The behavior of the UICollectionViewFlowLayout is not defined
because: the item width must be less than the width of the
UICollectionView minus the section insets left and right values, minus
the content insets left and right values.
Now the error is pretty straight forward, the cell itself has a length greater than that of the collection view. The reason for this is that in an outlier occurrence, there is a piece data that is just very long and causes the cell to go outside the bounds of the collection view.
On the cell itself, I have a line size of 1 and that the tail is truncated. It was my assumption that autolayout would handle this in such a way that if the cell is greater than the collection view width it would just use the width of the collection view on the cell and just truncate the text in the label. However, autolayout does not do this and the error above is produced repetitively in the console.
So now the question is what would be the best / correct way to handle this edge case?
Is there something small that I have missed?
Given this scenario I would have to 'Tweak' the flow layout, so would it be recommended to subclass the flow layout, override layoutAttributesForElementsInRect: and then adjust that cells size frame/size whenever it is greater than the bounds of the UICollectionView? This route seems like over kill the bug?
Add a less-than-or-equal width constraint to your custom UICollectionViewCell.
Create an outlet to that constraint and set it in collectionView(_:cellForItemAt:).
You may just use the following UICollectionViewDelegateFlowLayout method to dictate the size of the item at the given indexPath
func collectionView(_ collectionView: UICollectionView,
layout collectionViewLayout: UICollectionViewLayout,
sizeForItemAt indexPath: IndexPath) -> CGSize
For further details have a look at Apple’s documentation