Xcode unable to dequeue a cell with identifier - ios

my work is about `UITableView. Each time I run my project, this error appears :
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier Cell1 - must register a nib or a class for the identifier or connect a prototype cell in a storyboard
I checked a hundred times my cell identifier in my storyboard and in my code are the same.
Code (defaut code from UITableViewController) :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell1";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// Configure the cell...
return cell;
}
Picture of Table View Cell properties :
I created and implemented a subclass of UITableViewCell for my cell.
Any idea why this is not working ?
Any way (line of code) to know what is the identifier of a cell ?
Thanks
Edit : Screenshot of my interface builder.
Edit 2 : Text of customCell.h
#import <UIKit/UIKit.h>
#interface customCell : UITableViewCell
#end
New error appears when I run the project :
[<choixActiviteViewController 0x7591ac0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key Cell1.
choixActiviteViewController is a subclass of UITableViewController and is the custom class of Choix Activite View Controller.

Instead of:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
Try:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if this does not work then, also add:
if (cell == nil) {
cell = [[customCell alloc] init];
}

Ok, your problem is that you're using Static cells, instead of Prototype cells. Just change your UITableView Content type.

Ok, my project finally works. Some errors appeared about things I've deleted and I can't find anymore.
I've just deleted every TableViewCell I had to create a new unique UITableViewCell with the following properties :
class : customCell
Style : Basic (but it works also with Custom)
Identifier : Cell1
Thanks for your help ssantos, Abdullah Shafique and bilobatum.

If your table cell is a subclass of UITableViewCell, then you're not using the "Basic" style of cell. Change the style setting in the attributes inspector to Custom.
Also, make sure the Class in the table cell's Identity inspector is set to your custom table cell subclass.

I suppose you'r using static cells. If you'r doing that consciously - just delete thous methods from your .m file:
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
}

try to use customCell class instead UITableViewCell class.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell1";
customCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// Configure the cell...
return cell;
}

If you are intentionally using Static UITableViewCells, then you don't have to implement the normal UITableView population methods (numberOfSectionsInTableView:, tableView:numberOfRowsInSection:, tableView:cellForRowAtIndexPath:).
The UITableView will automatically populate from the cells defined in your storyboard. You do end up using the tableView:cellForRowAtIndexPath: in order to format the data in the cells. You use [super tableView:cellForRowAtIndexPath:] to get the tableViewCell and then ReuseIdentifier, tags, or indexPath to match the cell to the data that goes with it.

The reason for this issue is very clear from the exception:
One Solution to this problem is
register a class for the identifier
In Swift this can be done as follows
tableView.registerClass(UITableViewCell.classForKeyedArchiver(), forCellReuseIdentifier: "your_reuse_identifier")

In my case the Storyboard where I had defined the missing UITableViewCell was localised.

Comment out all of the code in application:didFinishLaunchingWithOptions(AppDelegate) but remain return YES, and try it again.

I was facing this issue when presenting the UITableViewController having a custom cell from another viewcontroller. As a workaround I instantiated it from the storyboard and that solved the issue.
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let controller = storyboard.instantiateViewController(withIdentifier: "YourTableViewController")
self.present(controller, animated: true, completion: nil)

Related

Custom prototype cell in UIStoryboard is created but doesn't show up in UITableView

I have a project where I need to use a custom UITableViewCell. I'm designing the cell as a prototype in storyboard and it looks fine there. I assign the prototype to my custom UITableViewCell subclass, give it the same reuse identifier I'm using in my UITableView and link the UILabel on the prototype cell to an IBOutlet in my UITableViewCell subclass.
When I call it from the UITableView the cell is created and if I add labels and buttons in the code of that class (create them with a CGRect and all) they all work but the labels I've added in the storyboard never show up.
I don't understand how my subclass can be called and created successfully but its layout and subviews from the storyboard don't seem to exist as far as my app is concerned. What am I doing wrong?
Here's my cellForRowAtIndexPath code
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
MyTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"cell" forIndexPath:indexPath];
// Configure the cell...
return cell;
}
I've run into this issue before, and in my case, the problem was that the auto-generated code for the view controller included a call to:
[UITableView registerClass:forCellReuseIdentifier:]
I would suggest checking for and removing any calls to the above, or to
[UITableView registerNib:forCellReuseIdentifier:]
and trying your original code again.
acreichman, add casting in cellForRow and put an NSLog in you cell's awakeFromNib to see if you get there. Let me know...
Your cellForIndexViewPath should look like this, to create a simple custom cell with label,
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"SimpleTableCell";
SimpleTableCell *cell = (SimpleTableCell *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil)
{
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:#"SimpleTableCell" owner:self options:nil];
cell = [nib objectAtIndex:0];
}
cell.nameLabel.text = [tableData objectAtIndex:indexPath.row];
return cell;
}
Make sure that you have made all connections well, set datasource and delegate to table and then set the “Identifier” of the custom cell to "MyTableViewCell" in “Attributes Inspector” like this,
For storyboard:
Add "MyTableViewCell" instead of "SimpleTableCell" as shown in above screenshot.

Unable to deque cell with identifier title

I am getting the following error when I press a button that opens a tableview:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier title - must register a nib or a class for the identifier or connect a prototype cell in a storyboard'
Here is the code in the view controller for the tableview and the method that's causing the problem:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *CellIdentifier = [menuItems objectAtIndex:indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
return cell;
}
I researched the error and I tried removing the forIndexPath:indexPath so the code looked like:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *CellIdentifier = [menuItems objectAtIndex:indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
return cell;
}
Now this caused a new error:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:
now I did some logging to find out that cell == nil was true so I added a check for that as suggested by some earlier questions:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *CellIdentifier = [menuItems objectAtIndex:indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if(cell == nil){
cell = [[UITableViewCell alloc] init]
}
return cell;
}
Now this removed all errors but now when I open the tableview, the cells are empty when I want the ones that I created in the storyboard.
How do I fix this problem?
Here is what the View Controller looks like in the storyboard:
there are two cell recycle methods you can call on a UITable
View,
-(UITableViewCell *) dequeueReusableCellWithIdentifier:forIndexPath:
-(UITableViewCell *)dequeueReusableCellWithIdentifier:
its somewhat confusing, but they are quite different in how they are used. The one which takes a second argument (of type NSIndexPath) is dependant on you first having registered a class or xib file with the tableView, in order that the tableView can create a cell ad-hoc for you when there isn't one handy for recycling. This first method will always return a cell, so you can code your cellForRowAtIndexPath: much like you have.
the second method (which takes only one argument, the (NSString *)cellIdentifier can and will return nil when there is no cell handy for recycling. So when you use this one you should test the result for nil and create a cell in that case.
eg
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString *cellId = #"cellID";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];
if (!cell) {
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellId];
}
//etc etc decorate your cell...
return cell;
}
In order to exploit your cell prototypes you will need to register a class or xib for each row/section, so that the table knows which cell to create. The recycling stuff only really works once enough cells have been created to fill the screen and you start scrolling. Good luck
If you are creating your prototype cells in a Storyboard you need to set the "Identifier" field for them to your "CellIdentifier" string. You can do this by selecting the cell and looking in the Attributes Inspector.
If you are creating a separate .xib file for your UITableViewCell you need to call this method on your UITableView in code somewhere:
registerNib:forCellReuseIdentifier:
If you are doing everything in code and just using a UITableViewCell subclass that knows how to layout itself then you need to call this method on your UITableView:
registerClass:forCellReuseIdentifier:
Here is a link to the reference docs

UITableView - "unable to dequeue a cell with identifier"

Where is the problem?
I want to make a Table View and if u click on the cell it pops up another Table View
What i must to do to fix that?
- (UITableViewCell )tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier2 = #"TableViewCell_2";
TableViewController_2 *cell2 = (TableViewController_2)[self.tableView dequeueReusableCellWithIdentifier:CellIdentifier2 forIndexPath:indexPath];
// Configure the cell...
int row = [indexPath row]; cell2.Spoj = _Spoj[row];
return cell2;
}
In your tableView:cellForRowAtIndexPath: use dequeueReusableCellWithIdentifier: instead of dequeueReusableCellWithIdentifier:forIndexPath:.
For correct dequeueing there are these steps:
On the attributes inspector for the xib file, add the identifier. (not in the restorationID field)
In your viewDidLoad of the ViewController owning the tableview, register the nib
[[self.tableview registerNib:[UINib nibWithName#"TheNibName" bundle:nil] withIdentifier:#"theSameIdentierInXib"];
call dequeue... in cellForRow (no need to cast cell type or check for nil from iOS 5+)
*note, registerClass can cause an assertion failure if used for cell xib.

Using alloc and init when using a UITableViewCell from Storyboard

I'm doing a simples app using Storyboard that a have a View with a UITableView with a UITableViewCell that do the navigation to another UIView.
So a have to code to populate the cell on the table view.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"SampleCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];
NSLog(#"cai no init da cell");
}
GPItem *item = [self.items objectAtIndex:indexPath.row];
cell.textLabel.text = #"Post";
cell.detailTextLabel.text = item.imageURL;
return cell;
}
I realised that the code if (cell == nil) { ... never executes so I really need to do that on uses the cell from Storyboard?
Thanks.
You are correct; that code is guaranteed to return a non-nil cell if you are using a storyboard. Also, in iOS 6, the new call dequeueReusableCellWithIdentifier:forIndexPath: never returns nil. See the discussion in my book:
http://www.apeth.com/iOSBook/ch21.html#_registering_a_cell_class
If you've declared your UITableViewCell in table view's prototype cells it's already allocated and just needs to be dequeued. If you're using a custom UITableViewCell subclass, then you must check if it's nil and allocate new entities when necessary.
Nope you don't need that code when using a cell made in your storyboard.
It is probably best to remove this code so that you crash nice and early if the identifier you gave to the cell in interface builder and the identifier you use in code ever drift. This snippet will mask this error and just provide a cell that you most likely was not intending to have.

Error while adding UICollectionView inside UITableViewCell

So I am trying to display horizontally scrollable collection view inside tableviewcell. the code i am using is
(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = (UITableViewCell *) [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
UICollectionViewController *cv = [self.storyboard instantiateViewControllerWithIdentifier:#"collectionViewID"];
cv.view.frame = cell.contentView.bounds;
[self addChildViewController:cv];
[cell.contentView addSubview:cv.view];
[cv didMoveToParentViewController:self];
return cell;
}
I am getting error: Object can not be nil. I'd appreciate if someone can help me out understanding the error.
I have done this in my app.
I found it much easier to subclass UITableViewCell. The I could put all the UICollectionView setup and the UICollectionView datasource and delegate inside the code for the cell.
I then provided one public property of type NSArray which I pass into the cell. The cell then uses this array as the datasource for the UICollectionView that it owns itself.
Made it a lot easier to manage.
check your UICollectionViewControlle's attribute inspector for identifier value {collectionViewID}
EDIT
[self addChildViewController:cv]; --> I think you want to add cv to the cell, isn't you?

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