Get real height size of a cell from UITableViewCell - xcode

On a custom UITableViewCell, what are the best location to have the real(custom) height of a cell.
I've try
override func awakeFromNib() {
btnIsFav.center.y = self.center.y
But look like awakeFromNib are called to soon to have the real info of the custom height.
Thanks :)

You should use layoutSubviews. that's when the cell begins to initialize its subviews

Related

UIStackView not calling draw of custom UIView

I have a UIView with a custom draw(_ rect: CGRect) method, which works.
However, when I place it inside a UIStackView, its draw method is not called. UILabel or UIImage inside the same stack view display normally.
In Interface Builder, it is drawn even inside the stack view, but when running on the device, it's not.
draw(_ rect: CGRect) doesn't call in addArrangedSubview of stack.
Instead you can put your code into layoutSubviews.
Solved it by adding a wrapper view first and after adding it to the UIStackView, i added my Custom-Drawing view into the wrapper view.
(This is written in C# but I'm pretty sure it'll help anyway)
UIView wrapperView = new UIView(f);
CanvasStackView.AddArrangedSubview(wrapperView);
CGRect f = new CGRect(CGPoint.Empty,new CGSize(CanvasStackView.Frame.Size.Width, height));
MyCustomView b = new MyCustomView(f);
wrapperView.AddSubview(b);

TableViewCell with UITextView not aligned and cutted until scolling

I've a TableViewCell with a UITextView, which content is not aligned and cutted at bottom at the first display:
When I scroll down and then up to the top, everything is fine:
My cellForRowAtIndexPath to get the content from a fetchedResultsController is simple:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("TextViewCell") as! TextViewCell
let data = self.fetchedResultsController.objectAtIndexPath(indexPath) as! NSManagedObject
let text = data.valueForKey("textDu")!.description
cell.textContentView.text = text
return cell
}
How can I get the result after scrolling after start???
Use sizeToFit() after adding content to your textContentView.
cell.textContentView.text = text
cell.textContentView.sizeToFit()
Make sure for sizing cell
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self,
selector: "onContentSizeChange:",
name: UIContentSizeCategoryDidChangeNotification,
object: nil)
tableView.estimatedRowHeight = 89
tableView.rowHeight = UITableViewAutomaticDimension
}
override func viewDidDisappear(animated: Bool) {
super.viewDidDisappear(animated)
NSNotificationCenter.defaultCenter().removeObserver(self)
}
func onContentSizeChange(notification: NSNotification) {
tableView.reloadData()
}
Hope it helps you.
In conjunction with #Ashish Kakkad's answer you may want to try to set heightDimensions in viewDidLoad or viewWillAppear:
yourTableView.estimatedRowHeight = 30.0 // Put a real estimate here
yourTableView.rowHeight = UITableViewAutomaticDimension
Use auto layout code to tie the bottom of the cells contentView to the bottom of the text box. When the text box resizes it'll expand the cell with it.
This is in addition to Asish's correct suggestion about automatic cell heights and is quite a high level suggestion as you need to do a few things to get auto layout working right in tableview cells but there's ample examples on that out on the web.
oh, oh. Think I found something. I removed the existing contraints and then I've tried to "add missing constaints". The result was thas the error "Failed to automatically update constraints". Seem's I've a problem with my storyboard-file...

UiScrollview with nested image looks weird

I have a UIScrollView inside a UIViewController (subclassed by ImageViewController). The ViewController itself is part of a NavigationController's stack. Now, apart from having a navigation bar, I want the ScrollView to take all of the available room on the screen. The UIImageView inside the scrollview should then fill the available room of the scroll view. You can see the current state at the bottom of this posting.
class ImageViewController: UIViewController, UIScrollViewDelegate {
#IBOutlet weak var scrollView: UIScrollView!
var imageView: UIImageView?
var image: UIImage?
override func viewDidLoad() {
super.viewDidLoad()
scrollView.delegate = self
if let image = image {
imageView = UIImageView(image: image)
if let imageView = imageView {
imageView.frame = CGRect(origin: CGPoint(x: 0, y: 0), size: image.size)
scrollView.addSubview(imageView)
scrollView.contentSize = image.size
let scaleHeight = scrollView.frame.size.height / scrollView.contentSize.height
let scaleWidth = scrollView.frame.size.width / scrollView.contentSize.width
let minimumScale:CGFloat = min(scaleHeight, scaleWidth)
let maximumScale:CGFloat = max(scaleHeight, scaleWidth)
scrollView.minimumZoomScale = minimumScale
scrollView.maximumZoomScale = maximumScale
scrollView.zoomScale = maximumScale
}
}
}
func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
return imageView
}
}
The code leaves me with unnecessary borders (left, right, top). How do I get rid of them?
EDIT: With #Bxtr's suggestion and another stackoverflow thread I was able to remove the borders left and right to the scroll view. After some more digging I found out that by deactivating Adjust Scroll View Insets, the image inside the scroll view can be correctly vertically positioned. Still, I do not get the reason for the vertical misplacement in the first place...
Have you checked the margin/padding values, because it kinda looks so (same size on left and right border). If it is not the case, could you please also post your xml file of the activity so we can have every part of the puzzle to help you ?
scrollView.contentSize = image.size;
you have to tweek this line. You are explicitly setting scroll view content size to the image size. You have to set content size to fit the Width of Screen.
You can use a UIView in UIScrollView, and that UIView contains UIImage.
You need to set constraints properly.
After some more digging I found out that by deactivating Adjust Scroll
View Insets, the image inside the scroll view can be correctly
vertically positioned. Still, I do not get the reason for the vertical
misplacement in the first place...
The reason is that the view controller's automaticallyAdjustsScrollViewInsets property is by default YES, the following is from apple documentation:
automaticallyAdjustsScrollViewInsets
A Boolean value that indicates
whether the view controller should automatically adjust its scroll
view insets.
Default value is YES, which allows the view controller to adjust its
scroll view insets in response to the screen areas consumed by the
status bar, navigation bar, and toolbar or tab bar. Set to NO if you
want to manage scroll view inset adjustments yourself, such as when
there is more than one scroll view in the view hierarchy.
Besides setting automaticallyAdjustsScrollViewInsets = No, you can pin the scrollView to the topLayoutGuide (instead of to the top of the viewController's view) when using autoLayout.

Custom TableViewCell with Subview whose height changes

I'm using a TableView and have a custom TableViewCell that I've added a subview to.
The problem is that I need the subview's height to change sometimes and therefore, the table's contentView would have to be updated as well as the row's height.
The subview of the custom TableViewCell is represented by the yellow background.
These images show what's currently happening in my simulator.
On Load
After the event that causes the subview's height to increase
What's the best approach to take with something like this?
Should I use constraints? And if so, what kind of constraints should I use? Would I have to then reload the tableview too every time the subview's size changes?
Here is the code I'm currently using for my custom TableViewCell:
import UIKit
class CustomCell: UITableViewCell {
var newView: UIView!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
self.newView = UIView(frame: self.frame)
self.newView.backgroundColor = .yellowColor()
self.addSubview(newView)
}
required init(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func layoutSubviews() {
super.layoutSubviews()
self.newView.frame.size.width = self.frame.size.width // because self.frame.width is different than it was in the init method
}
func somethingHappenedThatMySubviewHasToIncreaseInHeight() {
self.newView.frame.size.height = self.frame.size.height + 40
}
}
The best approach is to use Auto Layout and self-sizing cells. Setup constraints in storyboard for your custom cell.
You will not need to reload the tableView. Each cell will automatically adjust its height, based on how much vertical space its subview takes.
For more information, see the detailed walkthrough by smileyborg in his answer to Using Auto Layout in UITableView for dynamic cell layouts & variable row heights.

Setting minimum width of NSSplitViews

I'm having a heck of a time setting up a simple split view. The first split view is collapsed. I need to set a minimum width for it. Everything I see online (scarce for NSSplitViewController/NSSplitView) is for Objective-C, puts everything in the app delegate, and uses XIBs.
Here's the scenario:
Window Controller with a segue to a SplitView Controller, which has two split views (2 view controllers).
Which object needs to have the NSSplitViewDelegate?
EDIT: Adding code snippet:
For example, I have this:
import Cocoa
class ViewController: NSSplitViewController, NSSplitViewDelegate {
#IBOutlet weak var pdlSplitView: NSSplitView!
override func viewDidLoad() {
super.viewDidLoad()
}
override func splitView(splitView: NSSplitView, constrainMinCoordinate proposedMinimumPosition: CGFloat, ofSubviewAt dividerIndex: Int) -> CGFloat {
return proposedMinimumPosition + 200
}
}
Is there more that I'm missing?
Thanks
UPDATE
Based on comments below, I've made a change, but now I get a sigAbort on the class definition for the AppDelegate. Full code
ViewController:
import Cocoa
class ViewController: NSSplitViewController, NSSplitViewDelegate {
#IBOutlet weak var pdlSplitView: NSSplitView!
let publicDataListings : PDL = PDL()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
self.pdlSplitView.delegate = self
}
override func splitView(splitView: NSSplitView, constrainMinCoordinate proposedMinimumPosition: CGFloat, ofSubviewAt dividerIndex: Int) -> CGFloat {
return proposedMinimumPosition + 200
}
}
SidebarViewController:
import Cocoa
class SidebarViewController: NSViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do view setup here.
}
}
DatasetViewController:
import Cocoa
class DatasetViewController: NSViewController, NSSplitViewDelegate {
override func viewDidLoad() {
super.viewDidLoad()
// Do view setup here.
}
}
Update
I took away my custom NSSplitViewController class and created two NSSplitView classes, one with the constraint method. Now, I see both subviews, but they're far smaller than they should be:
Is there anyone at all that has done this with Swift and Storyboards?
No coding is required to set a minimum width in a storyboard with auto layout for a NSSplitViewController/NSSplitView.
Select the CustomView that you require a minimum width for (e.g. 200), and add a width constraint set to the required value which will add a "Equal" constraint (e.g. Custom View.Width equals 200).
Next locate that new constraint and change the constraint relation to "Greater Than or Equal" (e.g. so you now have width ≥ 200).
You now have a minimum width in an NSSplitView. You can then use the Priority field to resolve any conflicts with any other auto layout constraints.
These values are not exposed in the storyboard, which is a great shame, but NSSplitViewItem has minimumThickness and maximumThickness properties which you can use. (This overrides the holding priority, so if you set minimumThickness for one splitViewItem, the other one(s) will now shrink into nothing if you make the window small enough.)
There is also automaticMaximumThickness (I cannot work out how this interacts with the other values) and preferredThicknessFraction which had no effect when I played with it under 10.13.
Set NSSplitViewController as delegate of NSSplitView (the split view you want to constrain). In your case it should be - in xib hook the delegate outlet of the NSSplitView to file owner (I guess the file owner is NSSplitViewController subclass)
Implement
- (CGFloat)splitView:(NSSplitView *)splitView constrainMinCoordinate:(CGFloat)proposedMin ofSubviewAt:(NSInteger)dividerIndex { ... }
in NSSplitViewController
https://developer.apple.com/library/mac/documentation/Cocoa/Reference/NSSplitViewDelegate_Protocol/index.html#//apple_ref/occ/intfm/NSSplitViewDelegate/splitView:constrainMinCoordinate:ofSubviewAt:

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