As this video, (you can download source code from here, I've tried my best to remove all the unnecessary code)
I need to manually scroll through tableview to make it reset to the right height of each cell and if I expand and unexpand multiple cells, it will show the wrong height again.
I'm trying to use "systemLayoutSizeFittingSize" instead of "heightForRowAt". (CustomCell.swift)
override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
setNeedsLayout()
layoutIfNeeded()
let defaultHeight: CGFloat = 90
return CGSize(width: 0, height: !isExpanded ? defaultHeight : tableView.contentSize.height + defaultHeight)
}
I want to use autolayout instead of giving the exact height for tableview. what do I do wrong?
Related
i want to stretch collectionView height in tableView.
as the gitHub App's Label (below picture),
when the collectionViewCell's width excess collectionView's width,
I want to set collectionViewCell in a new line
To set cell in the new line, i tried to use flowlayout.
but it did not be increased height. just can scroll in collectionView. 😭.
unfortunately, tableView's height did not be increased
what's the best way to do this ?😂
This approach from SRP-Achiever should work.
override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
collectionView.layoutIfNeeded()
collectionView.frame = CGRect(x: 0, y: 0, width: targetSize.width , height: 1)
return collectionView.collectionViewLayout.collectionViewContentSize
}
I did what this answer said but it did not work why?
How to adjust height of UICollectionView to be the height of the content size of the UICollectionView?
but there is a problem its not resizing what am i missing out
I have also faced same issue so I did another approach. You need to add width constraint and you need to set it constant in systemLayoutSizeFitting function.
The main thing you should be careful about that is add all subviews to contentView of cell and also the last subview must has a constraint to bottom of contentView like the autoResizing TableViewCell
class ABCCell: UICollectionViewCell {
lazy var width: NSLayoutConstraint = {
let width = contentView.widthAnchor.constraint(equalToConstant: bounds.size.width)
width.isActive = true
return width
}()
override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
width.constant = bounds.size.width
return contentView.systemLayoutSizeFitting(CGSize(width: targetSize.width, height: 1))
}
}
I am using a UICollectionView for chat and using scroll to bottom on load. It's all working good except the first time I scroll manually it bounces up about 50-100 pt. If I continue scrolling it's fine and goes into the safe area and below the screen.
What is causing the initial bounce? It seems that it bounces off the top of the bottom safe area first, and then goes below the safe area fine if you continue scrolling.
What I'm trying to get is a nice smooth scroll initially without the weird bounce.
It seems to be caused by the fact that I am dynamically sizing image heights after they load with invalidateLayout.
I was able to solve this by luck with the following
AutoSizing cells: cell width equal to the CollectionView
// UICollectionViewController
if let layout = collectionView?.collectionViewLayout as? UICollectionViewFlowLayout {
layout.estimatedItemSize = CGSize(width: view.frame.width, height: 100)
}
// UICollectionViewCell
override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
let autoLayoutAttributes = super.preferredLayoutAttributesFitting(layoutAttributes)
// Specify you want _full width_
let targetSize = CGSize(width: layoutAttributes.frame.width, height: 200)
// Calculate the size (height) using Auto Layout
let autoLayoutSize = contentView.systemLayoutSizeFitting(targetSize, withHorizontalFittingPriority: UILayoutPriority.required, verticalFittingPriority: UILayoutPriority.defaultLow)
let autoLayoutFrame = CGRect(origin: autoLayoutAttributes.frame.origin, size: autoLayoutSize)
// Assign the new size to the layout attributes
autoLayoutAttributes.frame = autoLayoutFrame
return autoLayoutAttributes
}
Introduction
Context:
I'm creating one of my first apps but I've ran into an issue I cannot figure out.
I have tableView with cells packed with quite a few UIElements. All constraints are done using the EasyPeasy library which basically just sets auto layout constraints ( I have tried setting them manually also). The UITextView in question is constrained by various numbers to the left, right, top and bottom, I have no constraints on it for height or width.
in cellForRowAt indexPath: I set the textView delegate for each cells textView to self, using a delegate property declared within the cells custom class. I also tag every textView with its cells indexPath.row (gives textView.tag integer in textViewDidChange method).
Issue/acknowledgments:
After browsing SO a lot I've found a few questions alike this but I have not been able to make them work for me, I have implemented parts of them that felt logic to my case. I believe the problem differencing my situation from those questions lies in that for my cell design to work the cells has to have a height of itemHeight or higher.
I have noticed that as I type into the textview the textview itself increases in height (even below the cells border but its not visible as it reaches that point), however the cell itself doesn't resize.
I've tried with a cell that only contains a textView so the problem must lie in the textViewDidchange or heightForRowAt indexPath methods.
Question:
What am I doing wrong here? Why doesn't the cells height change dynamically as I type in the textView?
Code:
func textViewDidChange(_ textView: UITextView) {
var newframe = textView.frame
newframe.size.height = textView.contentSize.height - textView.frame.size.height + itemHeight[textView.tag]
textView.frame = newframe
let ndxPath = IndexPath(row: textView.tag, section: 0)
let cell = tableView.cellForRow(at: ndxPath) as! EventsCell
cell.frame = CGRect(x: cell.frame.origin.x, y: cell.frame.origin.y, width: cell.frame.width, height: textView.frame.height)
tableView.beginUpdates()
tableView.setNeedsLayout() //have tried without this line
tableView.layoutIfNeeded() //have tried without this line
tableView.endUpdates()
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
if UITableViewAutomaticDimension > itemHeight[indexPath.row] {
return UITableViewAutomaticDimension
} else {
return itemHeight[indexPath.row]
}
}
TextView constraints:
let containerView : UIView = {
let cv = UIView(frame: .zero)
cv.backgroundColor = .white
cv.translatesAutoresizingMaskIntoConstraints = false
cv.layer.cornerRadius = 7
return cv
}()
let eventText : GrowingTextView = { // GrowingTextView is a extension to a regular UITextView
let tv = GrowingTextView()
tv.allowsEditingTextAttributes = true
tv.isScrollEnabled = false
var delegate: UITextViewDelegate?
tv.textContainerInset = UIEdgeInsetsMake(1, 1, 0, 1)
tv.autoresizingMask = .flexibleHeight
tv.translatesAutoresizingMaskIntoConstraints = false
return tv
}()
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
containerView.addSubview(eventText)
contentView.addSubview(containerView)
containerView .easy.layout([Height(CGFloat(95 * itemCount)), Left(8), Right(8)])
eventText .easy.layout([Left(77), Right(5), Top(90), Bottom(4)])
}
Thanks for reading my post.
The constraints that determine the height should be laid out in such a way that the textView is attached directly to the top and bottom of the contentView or to views which are connected to the top and bottom of the contentView, so that autolayout can make out the height by connecting the constraints.
Make sure that you do not mention a height for the textView and disable scrolling. Let automatic dimension take care of all that.
Now all you need to do is call tableView.beginUpdates() and tableView.endUpdates() on textViewDidChange
Here is my repo which demonstrates the same.
OP Edit:
You should store the additional height that you add in a variable in the cell class so the cells can reload an appropriate height when the tableVIew is reloaded.
You should also change textViewDidChange method
cell.frame = CGRect(x: cell.frame.origin.x, y: cell.frame.origin.y, width: cell.frame.width, height: textView.frame.height)
to
let newFrame = ”originalCellHeight” - ”originalTextViewHeight” + textView.contentSize.height
cell.frame = CGRect(x: cell.frame.origin.x, y: cell.frame.origin.y, width: cell.frame.width, height: newFrame )`
I have collection view cells with equal width and height in a flow layout. They contain a single UILabel, which numberOfLines property is set to 0. The constraints of the label are:
The cell is made circular:
cell.layer.cornerRadius = cell.frame.width / 2
cell.clipsToBounds = true
I increase the size of each cell based on the label's text size. However, it's width and height can't be greater than 150. Here is how I determine the size of each cell:
private func estimatedFrameForText(text: String) -> CGRect {
let size = CGSize(width: 100, height: 1000)
let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
return NSString(string: text).boundingRect(with: size, options: options, attributes: [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 17)], context: nil)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let hashLabelText = textArray[indexPath.item]
let textSize = estimatedFrameForText(text: hashLabelText)
let width = min(150, textSize.width + 20)
let height = width
return CGSize(width: width, height: height)
}
With this I get the following result (I'm showing the part where the cells' width and height are equal to 150).:
As you can see, when the cell hits its maximum possible size and the text of the labels continues to increase, at some point, the text gets off the visible part of the cells. I understand why this happens (the layout debugger shows this clearly), however I can't find a solution to the problem, yet.
What I want is that the edges of the label remain visible no matter what is the size of the cell. The text's tail can be truncated if the cell reaches its maximum size, but the text continues to increase.
I've tried to increase the space between the label and the bounds of the cells but that affects how the text looks in the smallest cells. I've also tried to change the minimum font scale of the label, but again, without a success.
You have to use UIEdgeInsets for this, Create a class for UILabel:
import UIKit
class UILabelDraw: UILabel {
override func drawText(in rect: CGRect) {
let insets: UIEdgeInsets = UIEdgeInsets(top: 10.0, left: 10.0, bottom: 10.0, right: 10.0)
super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}
}
Use this class as a Label class like below:
Output of UIEdgeInsets is below: