I have a problem with the positioning of the elements inside a table cell. They change their position when I leaf through the table. I installed autoresizhe and indicated where they should be, but nalazeyut pictures to the text and I do not know how to fix them. I read a lot of articles but could not find a solution which is suitable for different devices. Please help me.
I have text and pictures change position on their own, when I leaf through or loaded a new cell in the table.
i add fixed size for uiimageview inside cellForRowAtIndexPath:
[cell.imageView setFrame:CGRectMake(0,0,self.view.frame.size.width,cell.imageView.frame.size.height)];
UPDATE:
i fixed my xib file. All constraints is blue. but the result is the same - bad. I do not know how to be. I suspect that the phone can not draw.
Since there is a warning and you discarded that warning for constraint the frame will be reset to that shown in yellow dotted rectangle. If any warning in the auto layout constraint, fix that first then only the IB will show correct frame that will be in run time.
If you need to set dynamic cell height based on the content you have, please refer this http://www.raywenderlich.com/73602/dynamic-table-view-cell-height-auto-layout
I assume you set the table cell height properly before you jump into any autolayout stuff
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return x; //x is your table cell xib height
}
After you do this, LEt's go to your table cell. You provided the leading trailing top and bottom for all your elements which is good.
You dont even need to mention this in your cellForRowAtIndex method:
[cell.imageView setFrame:CGRectMake(0,0,self.view.frame.size.width,cell.imageView.frame.size.height)];
If you are trying to change the imageview frame after you set the constraints, you need to call
[cell.imageView updateConstraints];
[cell updateConstraints];
If you see any yellow warning in the autolayout, try to resolve it first. Xcode will suggest you some fixes for it, see that works for you ,by selecting element that has yellow warning and click on update frame option in storyboard.
See if it works!!!
I've build a UITableView with different costum cells. One is with a UIImageView and one without. But they are overlaying each other. I've set all constraints.
every cell owns its own section.
screens:
(image and text are samples.)
Does the actual cell height change?
If so, you need to make sure you're returning the correct height with:
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
return heightOfCell;
}
It looks like you might have the constraints wrong on the cell without the image as it is drawing beyond where the table thinks the height suggests it should end. Hence why it is drawing beyond where the second cell top starts.
Possible issues are:
0) You are returning a height from heightForRowAtIndexPath which is too small. Use auto layout for iOS8 or if suppoting iOS7, you will need to calculate the height.
1) Perhaps your constraints are wrong. Have you pinned the bottom text to the bottom of the cell contentView and the top of the date to the top of the contentView?
2) If using iOS8 auto layout, try adding [self.tableView reloadData]; in viewWillAppear. Sometimes it needs an extra kick to get the layout right, especially if text needs resized. I have no explanation for this other than I had to do this and I've seen it mentioned a few times elsewhere.
After updating to Xcode 6.1 beta 2 when I run my app that contains tableview cells, the debug assistant says:
Warning once only: Detected a case where constraints ambiguously suggest a height of zero for a tableview cell's content view. We're considering the collapse unintentional and using standard height instead.
Before, when I used Xcode 5 on this project, I would get a few errors but those have gone away since I upgraded. I have no other errors or warnings now. I have already tried adjusting the sizes of all the tableview cells and also tried using standard height but I still get the same warning:
Warning once only: Detected a case where constraints ambiguously suggest a height of zero for a tableview cell's content view. We're considering the collapse unintentional and using standard height instead.
I have also read through all similar topics on this but none of their solutions help. When I test the app with the simulator, the app runs fine except the pictures that are supposed to be in the tableView cells aren't there.
You're encountering the side effect of a fantastic new feature in iOS8's Tableviews: Automatic Row Heights.
In iOS 7, you either had rows of a fixed size (set with tableView.rowHeight), or you'd write code to calculate the height of your cells and you'd return that in tableView:heightForRowAtIndexPath. Writing code for the calculation of a cell's height could be quite complex if you had numerous views in your cell and you had different heights to consider at different font sizes. Add in Dynamic Type and the process was a pain in the ass.
In iOS 8, you can still do the above, but now the height of the rows can be determined by iOS, provided that you've configured the content of your cell using Auto Layout. This is huge benefit for developers, because as the dynamic font size changes, or the user modifies the text size using Accessibility Settings, your UI can be adaptive to the new size. It also means if you have a UILabel that can have multiple rows of text, your cell can now grow to accommodate those when the cells needs to, and shrink when it does not, so there isn't any unnecessary whitespace.
The warning message you're seeing is telling you that there aren't enough constraints in your cell for Auto Layout to inform the tableview of the height of the cell.
To use dynamic cell height, which, along with the techniques already mentioned by other posters, will also get rid of this message, you need to ensure your cell has sufficient constraints to bind the UI items to the top and bottom of the cell. If you've used Auto Layout before, you are probably accustomed to setting Top + Leading constraints, but dynamic row height also requires bottom constraints.
The layout pass works like this, which occurs immediately before a cell is displayed on screen, in a just-in-time manner:
Dimensions for content with intrinsic sizes is calculated. This includes UILabels and UIImageViews, where their dimensions are based on the text or UIImages they contain, respectively. Both of these views will consider their width to be a known (because you've set constraints for trailing/leading edges, or you set explicit widths, or you used horizontal constraints that eventually reveal a width from side to side). Let's say a label has a paragraph of text ("number of lines" is set to 0 so it'll auto-wrap), it can only be 310 points across, so it's determined to be 120pt high at the current font size.
The UI is laid out according to your positioning constraints. There is a constraint at the bottom of the label that connects to the bottom margin of the cell. Since the label has grown to be 120 points tall, and since it's bound to the bottom of the cell by the constraint, it must push the cell "down" (increasing the height of the cell) to satisfy the constraint that says "bottom of the label is always standard distance from the bottom of the cell.
The error message you reported occurs if that bottom constraint is missing, in which case there is nothing to "push" the bottom of the cell away from the top of the cell, which is the ambiguity that's reported: with nothing to push the bottom from the top, the cell collapses. But Auto Layout detects that, too, and falls back to using the standard row height.
For what it's worth, and mostly to have a rounded answer, if you do implement iOS 8's Auto Layout-based dynamic row heights, you should implement tableView:estimatedHeightForRowAtIndexPath:. That estimate method can use rough values for your cells, and it'll be called when the table view is initially loaded. It helps UIKit draw things like the scrollbar, which can't be drawn unless the tableview knows how much content it can scroll through, but does't need totally accurate sizes, since it's just a scrollbar. This lets the calculation of the actual row height be deferred until the moment the cell is needed, which is less computationally intensive and lets your UITableView be presented quicker.
Three things have managed to silence this warning so far. You can pick up the most convenient for you. Nothing pretty though.
To set up default cell's height in viewDidLoad
self.tableView.rowHeight = 44;
Go to storyboard and change row height on your tableview to something different than 44.
To implement tableview's delegate method heightForRowAtIndexPath
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return 44;
}
Weird.
To resolve this without a programmatic method, adjust the row height of the table view in the Size Inspector from the storyboard.
I had this problem after creating a custom UITableViewCell and adding my subviews to the cell instead of its contentView.
This is an autolayout issue. Make sure that your subviews have all the constraints. For me, the bottom constraint was missing for the Title Label in the cell. When I added that, the warning went away and everything showed up perfectly.
Just enable Self-Sizing Table View Cells
tableView.estimatedRowHeight = 85.0
tableView.rowHeight = UITableViewAutomaticDimension
& make sure you added constraints on all sides of UITableViewCell as-
Example Link 1
Example Link 2
If u are using static cell or dynamic cell ,simply add some row height to table view in inspector table and uncheck the automatic to the right side of row height ,that's it u will stop getting this warning .
I got this warning today. Here is what made it disappear for me(in interface builder)
1.Set the row height field for the table view to something other than 44
2 Set the row height field for the tableView cell to something other than 44
I did not have to make any changes in code
In my case, I was building the cell programmatically and kept getting this error.
I was adding the subviews and constraints in the UITableViewCell's init method like this:
addSubview(rankingLabel)
addConstraints(cellConstraints)
I solved the issue by adding them to the cell's contentView instead:
contentView.addSubview(rankingLabel)
contentView.addConstraints(cellConstraints)
Set the estimated row height to zero and the warning disappears:
If you have created a Custom tableViewCell for tableView, make sure you have given both bottom and top constraints to you cells,
you could also get this message if your subviews inside custom cells are aligned in center Y which wouldnt pop any error message but would mess up with identifying height of row for tableview in turn like in Image I have attached , here we have both top and bottom constraints
When you create a Custom Cell for tableView you must specific row height or top and bottom constraints for you custom cell's subviews inside cell (e.g. label in custom cell like in below image)
But if this doesn't work you can try setting row height for your cell instead of being automatic like in this image
But be sure if you turn that automatic tick off you have to adjust your row size for changes programmatically which could have been done automatically
I got this Warning today All I did is just added one extra line to my code
tableView.rowHeight = 200;
add this line of code inside the
func tableView(_ tableView: UITableView, numberOfRowsInSection section:Int) -> Int {
...
}
and the final code look like
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
tableView.rowHeight = 200;
...
}
this code will increase the table Row cell height to 200 the default height is 44
I too experienced this warning with moving to Xcode 6 GM. I was only getting the warning when I rotated the device back to its original position.
I am using custom UITableViewCells. The storyboard table view is set to my custom size (100.0 in my case). While the table cells render properly as they have in previous releases, I did not like warning message.
In addition to the above ideas, I added this
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
return 100.0;
}
Screen renders... responds to rotation and no more warning messages.
In xcode 6.0.1 I had removed this warnings specifying the row height using:
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
return 44.0;
}
You may also see this message if your only constraints are set to align all items vertically and you don't have/want a height specified for the cell. If you set a top/bottom constraint on the item the warning will disappear.
I had this problem when my labels and views in the custom tableViewCell were constrained to the customCell, not its Content View. When I cleared the constraints and connected them to cells Content View the problem was solved.
I had the same error message,
make sure all your outlets are valid like table view and tableview Constraints
I have also similar issue for custom tableview cell which has dynamic row height. Dynamic height wasn't reflected and got the same warning in console. The solution is Adding subviews to cell instead of contentView. BTW, I have created subviews programatically.
I have this issue on TableViewCells where the constraints are set on initialisation but where the cell's contents are loaded afterwards, this means the autolayout engine can't determine the height. The other solutions here don't work because I need the cell's height to be UITableView.automaticDimension.
I just added an extra constraint to the cell:
contentView.heightAnchor.constraint(equalToConstant: 44, priority: .defaultLow)
In the storyboard set the cell Row height field with the same value as Row height in tableView (both with the same value worked for me).
If you add heightForRowAtIndexPath function to your code it may induce a performance issue because it will be called for each cell so be careful.
If you are making a dynamic height calculation,
you should have all elements linked to each other in terms of constraints like top and bottom.
you should definitely have a bottom constraint that is linked to the element at the bottom of your cell
if you are extending your ViewController class with UITableView and also using navigation controller to show the screen then you dont need to perform segue with identifier this may cause an error of identifier ViewController, you can use pushViewController method to show the chat screen in order to get rid from this error so here is the code just paste it in to your UItableView delegate
let chatBox = ChatBoxViewController()
navigationController?.pushViewController(chatBox, animated: true)
just put the name of your viewcontroller which you want to show next and yeah done.
I have same error, due to this line this error was shown.
self.layer.backgroundColor = UIColor(white: 1, alpha: 0.2) as! CGColor
I just change the line as following to fix the error
self.layer.backgroundColor = UIColor(white: 1, alpha: 0.2).cgColor
I have a strange issue with the height of the table view cells. I'm creating a custom grouped style UITableView in the storyboard. I have 4 different prototype cells for a single, top, middle and a bottom cell. Each of them has a different height. I'm already setting those heights in the storyboard, and I've also implemented the delegate method
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
Just for an example: The single cell should have a height of 48. So I set the height in the storyboard to 48 and the above mentioned delegate method returns the value 48. But if I take a look at the screenshot, the single cell has actually a height of 49.
There is the same behavior for the top cell, but not for the middle and the bottom cell. That makes it even stranger.
Do you have any ideas? Where comes this extra pixel from?
I don't know exactly but it may be reason check the height of the header and footer .
I have got a UITableView in my ViewController and it's row has custom content. Every cell's height dynamically calculated according to cell's content with - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath method.
But how can set UITableView's height?
Because if my table contains only one row, after row i see a big whitespace in my table?
Isn't there any property to set table's height dynamically increase or reduce according to its contents?
The contentSize will be adjusted as needed by the number of rows and sections you have, if you want to change the actual size of the table view you should adjust the frame property
you might just be better off putting a backgroundView or colour on the table if its that the white background when you only have a few rows is bothering you
Try the contentSize method, which is inherited from UITableView’s superclass, UIScrollView. However, you may find that contentSize returns an incorrect or out of date value, so you should probably call layoutIfNeeded first to recalculate the table’s layout.
[tableView layoutIfNeeded];
// Allows you to perform layout before the drawing cycle happens. //-layoutIfNeeded forces layout early. So it will correctly return the size. Like dreaming before doing.
CGSize tableSize=tableView.contentSize;