Related
So I was making an rss reader for my school and finished the code. I ran the test and it gave me that error. Here is the code it's referring to:
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell =
[tableView dequeueReusableCellWithIdentifier:CellIdentifier
forIndexPath:indexPath];
if (cell == nil) {
cell =
[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle
reuseIdentifier:CellIdentifier];
}
here's the error in the output:
2012-10-04 20:13:05.356 Reader[4390:c07] * Assertion failure in
-[UITableView dequeueReusableCellWithIdentifier:forIndexPath:], /SourceCache/UIKit_Sim/UIKit-2372/UITableView.m:4460 2012-10-04
20:13:05.357 Reader[4390:c07] * Terminating app due to uncaught
exception 'NSInternalInconsistencyException', reason: 'unable to
dequeue a cell with identifier Cell - must register a nib or a class
for the identifier or connect a prototype cell in a storyboard'
* First throw call stack: (0x1c91012 0x10cee7e 0x1c90e78 0xb64f35 0xc7d14 0x39ff 0xd0f4b 0xd101f 0xb980b 0xca19b 0x6692d 0x10e26b0
0x228dfc0 0x228233c 0x228deaf 0x1058cd 0x4e1a6 0x4ccbf 0x4cbd9 0x4be34
0x4bc6e 0x4ca29 0x4f922 0xf9fec 0x46bc4 0x47311 0x2cf3 0x137b7 0x13da7
0x14fab 0x26315 0x2724b 0x18cf8 0x1becdf9 0x1becad0 0x1c06bf5
0x1c06962 0x1c37bb6 0x1c36f44 0x1c36e1b 0x147da 0x1665c 0x2a02 0x2935)
libc++abi.dylib: terminate called throwing an exception
and here's the code it shows in the error screen:
int main(int argc, char *argv[])
{
#autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
}
please help!
You're using the dequeueReusableCellWithIdentifier:forIndexPath: method. The documentation for that method says this:
Important: You must register a class or nib file using the registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier: method before calling this method.
You didn't register a nib or a class for the reuse identifier "Cell".
Looking at your code, you seem to expect the dequeue method to return nil if it doesn't have a cell to give you. You need to use the dequeueReusableCellWithIdentifier: for that behavior:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
Notice that dequeueReusableCellWithIdentifier: and dequeueReusableCellWithIdentifier:forIndexPath: are different methods. See doc for the former and the latter.
If you want to understand why you'd want to ever use dequeueReusableCellWithIdentifier:forIndexPath:, check out this Q&A.
I think this error is about registering your nib or class for the identifier.
So that you may keep what you are doing in your tableView:cellForRowAtIndexPath function and just add code below into your viewDidLoad:
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
It's worked for me. Hope it may help.
Although this question is fairly old, there is another possibility:
If you are using Storyboards, you simply have to set the CellIdentifier in the Storyboard.
So if your CellIdentifier is "Cell", just set the "Identifier" property:
Make sure to clean your build after doing so. XCode sometimes has some issues with Storyboard updates
i had the same problem replacing with
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell==nil) {
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
}
solved
The problem is most likely because you config custom UITableViewCell in storyboard but you do not use storyboard to instantiate your UITableViewController which uses this UITableViewCell. For example, in MainStoryboard, you have a UITableViewController subclass called MyTableViewController and have a custom dynamic UITableViewCell called MyTableViewCell with identifier id "MyCell".
If you create your custom UITableViewController like this:
MyTableViewController *myTableViewController = [[MyTableViewController alloc] init];
It will not automatically register your custom tableviewcell for you. You have to manually register it.
But if you use storyboard to instantiate MyTableViewController, like this:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
MyTableViewController *myTableViewController = [storyboard instantiateViewControllerWithIdentifier:#"MyTableViewController"];
Nice thing happens! UITableViewController will automatically register your custom tableview cell that you define in storyboard for you.
In your delegate method "cellForRowAtIndexPath", you can create you table view cell like this :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"MyCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
//Configure your cell here ...
return cell;
}
dequeueReusableCellWithIdentifier will automatically create new cell for you if there is not reusable cell available in the recycling queue.
Then you are done!
I'll just add that Xcode 4.5 includes the new dequeueReusableCellWithIdentifier:forIndexPath:
in its default template code - a potential gotcha for developers expecting the older dequeueReusableCellWithIdentifier: method.
Swift 2.0 solution:
You need to go into your Attribute Inspector and add a name for your cells Identifier:
Then you need to make your identifier match with your dequeue like this:
let cell2 = tableView.dequeueReusableCellWithIdentifier("ButtonCell", forIndexPath: indexPath) as! ButtonCell
Alternatively
If you're working with a nib you may need to register your class in your cellForRowAtIndexPath:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "SwitchCell")
// included for context
let cell = tableView.dequeueReusableCellWithIdentifier("SwitchCell", forIndexPath:indexPath) as! SwitchCell
//... continue
}
Apples's UITableView Class Reference says:
Prior to dequeueing any cells, call this method or the
registerNib:forCellReuseIdentifier: method to tell the table view how
to create new cells. If a cell of the specified type is not currently
in a reuse queue, the table view uses the provided information to
create a new cell object automatically.
If you previously registered a class or nib file with the same reuse
identifier, the class you specify in the cellClass parameter replaces
the old entry. You may specify nil for cellClass if you want to
unregister the class from the specified reuse identifier.
Here's the code from Apples Swift 2.0 framework:
// Beginning in iOS 6, clients can register a nib or class for each cell.
// If all reuse identifiers are registered, use the newer -dequeueReusableCellWithIdentifier:forIndexPath: to guarantee that a cell instance is returned.
// Instances returned from the new dequeue method will also be properly sized when they are returned.
#available(iOS 5.0, *)
func registerNib(nib: UINib?, forCellReuseIdentifier identifier: String)
#available(iOS 6.0, *)
func registerClass(cellClass: AnyClass?, forCellReuseIdentifier identifier: String)
In your storyboard you should set the 'Identifier' of your prototype cell to be the same as your CellReuseIdentifier "Cell". Then you won't get that message or need to call that registerClass: function.
If you are going with Custom Static Cells just comment this method:
//- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
// static NSString *CellIdentifier = #"notificationCell";
// UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// return cell;
//}
and give the cells an identifier at "Attributes Inspector" in storyboard.
I give you the answer in both Objective C and Swift.Before that I want to say
If we use the dequeueReusableCellWithIdentifier:forIndexPath:,we must register a class or nib file using the registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier: method before calling this method as
Apple Documnetation Says
So we add registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier:
Once we registered a class for the specified identifier and a new cell must be created, this method initializes the cell by calling its initWithStyle:reuseIdentifier: method. For nib-based cells, this method loads the cell object from the provided nib file. If an existing cell was available for reuse, this method calls the cell’s prepareForReuse method instead.
in viewDidLoad method we should register the cell
Objective C
OPTION 1:
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"cell"];
OPTION 2:
[self.tableView registerNib:[UINib nibWithNibName:#"CustomCell" bundle:nil] forCellReuseIdentifier:#"cell"];
in above code nibWithNibName:#"CustomCell" give your nib name instead of my nib name CustomCell
SWIFT
OPTION 1:
tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "cell")
OPTION 2:
tableView.registerNib(UINib(nibName: "NameInput", bundle: nil), forCellReuseIdentifier: "Cell")
in above code nibName:"NameInput" give your nib name
Working with Swift 3.0:
override func viewDidLoad() {
super.viewDidLoad()
self.myList.register(UINib(nibName: "MyTableViewCell", bundle: nil), forCellReuseIdentifier: "Cell")
}
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = myList.dequeueReusableCell(withIdentifier: "Cell", for: indexPath as IndexPath) as! MyTableViewCell
return cell
}
I spent hours last night working out why my programmatically generated table crashed on [myTable setDataSource:self]; It was OK commenting out and popping up an empty table, but crashed every time I tried to reach the datasource;
I had the delegation set up in the h file: #interface myViewController : UIViewController
I had the data source code in my implementation and still BOOM!, crash every time! THANK YOU to "xxd" (nr 9): adding that line of code solved it for me! In fact I am launching a table from a IBAction button, so here is my full code:
- (IBAction)tapButton:(id)sender {
UIViewController* popoverContent = [[UIViewController alloc]init];
UIView* popoverView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 200, 300)];
popoverView.backgroundColor = [UIColor greenColor];
popoverContent.view = popoverView;
//Add the table
UITableView *table = [[UITableView alloc] initWithFrame:CGRectMake(0, 0, 200, 300) style:UITableViewStylePlain];
// NEXT THE LINE THAT SAVED MY SANITY Without it the program built OK, but crashed when tapping the button!
[table registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
table.delegate=self;
[table setDataSource:self];
[popoverView addSubview:table];
popoverContent.contentSizeForViewInPopover =
CGSizeMake(200, 300);
//create a popover controller
popoverController3 = [[UIPopoverController alloc]
initWithContentViewController:popoverContent];
CGRect popRect = CGRectMake(self.tapButton.frame.origin.x,
self.tapButton.frame.origin.y,
self.tapButton.frame.size.width,
self.tapButton.frame.size.height);
[popoverController3 presentPopoverFromRect:popRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}
#Table view data source in same m file
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
NSLog(#"Sections in table");
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
NSLog(#"Rows in table");
// Return the number of rows in the section.
return myArray.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
NSString *myValue;
//This is just some test array I created:
myValue=[myArray objectAtIndex:indexPath.row];
cell.textLabel.text=myValue;
UIFont *myFont = [ UIFont fontWithName: #"Arial" size: 12.0 ];
cell.textLabel.font = myFont;
return cell;
}
By the way: the button must be linked up with as an IBAction and as a IBOutlet if you want to anchor the popover to it.
UIPopoverController *popoverController3 is declared in the H file directly after #interface between {}
FWIW, I got this same error when I forgot to set the cell identifier in the storyboard. If this is your issue then in the storyboard click the table view cell and set the cell identifier in the attributes editor. Make sure the cell identifier you set here is the same as
static NSString *CellIdentifier = #"YourCellIdenifier";
I had the same issue, was having the same error and for me it worked like this:
[self.tableView registerNib:[UINib nibWithNibName:CELL_NIB_HERE bundle: nil] forCellReuseIdentifier:CELL_IDENTIFIER_HERE];
Maybe it will be usefull for someone else.
I setup everything correctly in the Storyboard and did a clean build but kept getting the error " must register a nib or a class for the identifier or connect a prototype cell in a storyboard"
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
Corrected the error but i'm still at a loss. I'm not using a 'custom cell', just a view with a tableview embeded. I have declared the viewcontroller as delegate and datasource and made sure the cell identifier matches in file. whats going on here?
This might seem stupid to some people but it got me. I was getting this error and the problem for me was that I was trying to use static cells but then dynamically add more stuff. If you are calling this method your cells need to be dynamic prototypes. Select the cell in storyboard and under the Attributes inspector, the very first thing says 'Content' and you should select dynamic prototypes not static.
Just a supplement of the answers:
There may be a time you set all things right, but you may accidentally add some other UIs in you .xib, like a UIButton:
Just delete the extra UI, it works.
Make sure that the CellIdentifier == identifier of the cell in a storyboard, both names are same. Hope this works for u
In my case, the crash happened when I calleddeselectRowAtIndexPath:
The line was [tableView deselectRowAtIndexPath:indexPath animated:YES];
Changing it to [self.tableView deselectRowAtIndexPath:indexPath animated:YES]; FIXED MY PROBLEM!
Hope this helps anyone
In Swift this problem can be solved by adding the following code in your
viewDidLoad
method.
tableView.registerClass(UITableViewCell.classForKeyedArchiver(), forCellReuseIdentifier: "your_reuse_identifier")
you have to be aware that when using interface builder and creating a Xib (nib) containing one cell that there is also a placeholder created that points to the class that will be used. Meaning, when you place two UITableViewCell in one Xib file you possibly run into the exact same trouble causing an *** Assertion failure .... The placeholder mechanism doesn't work adn will be confused then. Instead placing different placeholders in one Xib read on..
The most easy solution (even if that seems a bit to simple) is to place one Cell at a time in one Xib. IB will create a placeholder for you and all works as expected then. But this then leads directly to one extra line of code, because then you need to load the correct nib/xib asking for the reuseIdentified Cell where it resides in.
So the following example code focuses the use of multiple Cell Indentifiers in one tableview where an Assertion Failure is very common.
// possibly above class implementation
static NSString *firstCellIdentifier = #"firstCellIdentifier";
static NSString *secondCellIdentifier = #"secondCellIdentifier";
// possibly in -(instancetype)init
UINib *firstNib = [UINib nibWithNibName:#"FirstCell" bundle:nil];
[self.tableView registerNib:firstNib forCellReuseIdentifier:firstCellIdentifier];
UINib *secondNib = [UINib nibWithNibName:#"SecondCell" bundle:nil];
[self.tableView registerNib:secondNib forCellReuseIdentifier:secondCellIdentifier];
Another trouble with the use of two CellIdentifier's in one UITableView is that row height and/or section height have to be taken care of. Two cells can have different heights of course.
When registering classes for reuse the code should look different.
The "simple solution" looks also much different when your cells reside inside a Storyboard instead of Xib's. Watch out for the placeholders.
Keep also in mind that interface builder files have version wise variations and need to be set to a version that your targeted OS version supports. Even if you may be lucky that the particular feature you placed in your Xib is not changed since the last IB version and does not throw errors yet. So a Xib made with IB set to be compatible to iOS 13+ but used in a target that is compiled on an earlier version iOS 12.4 will cause also trouble and can end up with Assertion failure.
Ran into this error bc cell re-use identifier was wrong-- a rookie mistake but it happens:
1. Makes SURE cell re-use idenifier has no misspellings or missing letters.
2. Along same line, don't forget capitalization counts.
3. Zeroes are not "O"s (Ohs)
I have seen the other questions about cleaning up the connections in the nibs, but I don't believe that is my problem.
Currently I'm importing a custom UITableViewCell class, registering the nib in the VC with the UITableView in that VC's viewDidLoad as follows:
static NSString *cellIdentifier = #"cell";
UINib* cellNib = [UINib nibWithNibName:#"[nib for the custom cell]" bundle:[NSBundle mainBundle]];
[_theTableView registerNib:cellNib forCellReuseIdentifier:cellIdentifier];
Then later in the VC I implement the method
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString* cellIdentifier = #"cell";
CustomTableCell* cell = [tableView dequeueReusableCellWithIdentifier:outgoingNoteIdentifier forIndexPath:indexPath];
return cell;
}
If I don't connect any of the properties in the custom cell (just labels and buttons), then it loads fine, and I can see the images associated with both the labels and the buttons. When I try to connect just one of the properties in the xib file though, I get the above mentioned error.
it sounds like you are connecting your Nib outlets to the file's owner.
Try connection them directly to the cell instead.
I usually follow this flow:
Set file's owner to your custom cell class
Add outlets to file's owner, to get generated properties
Set cell's Custom Class to be same as the one specified as file's owner
Add all outlets to the cell. XCode will now show the properties your created in step 2
Happy coding
I'm trying to create a table view with some custom cells, but I have a problem. Everything is setup correctly and when I use this UITableVC as the initial VC it all works. But when I try to add it as a child VC to another VC, I get this error:
Assertion failure in -[UITableView dequeueReusableCellWithIdentifier:forIndexPath:], /SourceCache/UIKit_Sim/UIKit-2372/UITableView.m:4460
2013-02-05 18:37:25.704 SalesBot[16284:c07] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier Statement Cell - must register a nib or a class for the identifier or connect a prototype cell in a storyboard'
I'm not changing anything else, I'm just moving the arrow in the storyboard to another VC to make it initial.
Here is how I'm adding the UITableVC subclass as a child to another VC:
self.statementTableViewController = [[SBStatementTableViewController alloc] init];
[self.view addSubview:self.statementTableViewController.view];
[self.statementTableViewController.view setFrame:self.contentFrame];
And here is how I dequeue a cell:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Statement Cell";
SBStatementCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// Configure the cell...
return cell;
}
I understand the above code is iOS6 only, I will worry about iOS 5 later :)
I'm guessing that the cell identifiers are somehow not "global" and the tableVC can't see them when it's a child to another VC?
Please help and let me know if you need to see some more code!
Even though you have yet to follow up with your code, I'm willing to bet this is your issue.
Taken from: Assertion failure in dequeueReusableCellWithIdentifier:forIndexPath:
You're using the dequeueReusableCellWithIdentifier:forIndexPath: method. The documentation for that method says this:
Important: You must register a class or nib file using the
registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier:
method before calling this method.
You didn't register a nib or a class for the reuse identifier "Cell".
Looking at your code, you seem to expect the dequeue method to return nil if it doesn't have a cell to give you. You need to use the dequeueReusableCellWithIdentifier: for that behavior:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
Notice that dequeueReusableCellWithIdentifier: and dequeueReusableCellWithIdentifier:forIndexPath: are different methods.
So I was making an rss reader for my school and finished the code. I ran the test and it gave me that error. Here is the code it's referring to:
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell =
[tableView dequeueReusableCellWithIdentifier:CellIdentifier
forIndexPath:indexPath];
if (cell == nil) {
cell =
[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle
reuseIdentifier:CellIdentifier];
}
here's the error in the output:
2012-10-04 20:13:05.356 Reader[4390:c07] * Assertion failure in
-[UITableView dequeueReusableCellWithIdentifier:forIndexPath:], /SourceCache/UIKit_Sim/UIKit-2372/UITableView.m:4460 2012-10-04
20:13:05.357 Reader[4390:c07] * Terminating app due to uncaught
exception 'NSInternalInconsistencyException', reason: 'unable to
dequeue a cell with identifier Cell - must register a nib or a class
for the identifier or connect a prototype cell in a storyboard'
* First throw call stack: (0x1c91012 0x10cee7e 0x1c90e78 0xb64f35 0xc7d14 0x39ff 0xd0f4b 0xd101f 0xb980b 0xca19b 0x6692d 0x10e26b0
0x228dfc0 0x228233c 0x228deaf 0x1058cd 0x4e1a6 0x4ccbf 0x4cbd9 0x4be34
0x4bc6e 0x4ca29 0x4f922 0xf9fec 0x46bc4 0x47311 0x2cf3 0x137b7 0x13da7
0x14fab 0x26315 0x2724b 0x18cf8 0x1becdf9 0x1becad0 0x1c06bf5
0x1c06962 0x1c37bb6 0x1c36f44 0x1c36e1b 0x147da 0x1665c 0x2a02 0x2935)
libc++abi.dylib: terminate called throwing an exception
and here's the code it shows in the error screen:
int main(int argc, char *argv[])
{
#autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
}
please help!
You're using the dequeueReusableCellWithIdentifier:forIndexPath: method. The documentation for that method says this:
Important: You must register a class or nib file using the registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier: method before calling this method.
You didn't register a nib or a class for the reuse identifier "Cell".
Looking at your code, you seem to expect the dequeue method to return nil if it doesn't have a cell to give you. You need to use the dequeueReusableCellWithIdentifier: for that behavior:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
Notice that dequeueReusableCellWithIdentifier: and dequeueReusableCellWithIdentifier:forIndexPath: are different methods. See doc for the former and the latter.
If you want to understand why you'd want to ever use dequeueReusableCellWithIdentifier:forIndexPath:, check out this Q&A.
I think this error is about registering your nib or class for the identifier.
So that you may keep what you are doing in your tableView:cellForRowAtIndexPath function and just add code below into your viewDidLoad:
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
It's worked for me. Hope it may help.
Although this question is fairly old, there is another possibility:
If you are using Storyboards, you simply have to set the CellIdentifier in the Storyboard.
So if your CellIdentifier is "Cell", just set the "Identifier" property:
Make sure to clean your build after doing so. XCode sometimes has some issues with Storyboard updates
i had the same problem replacing with
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell==nil) {
cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
}
solved
The problem is most likely because you config custom UITableViewCell in storyboard but you do not use storyboard to instantiate your UITableViewController which uses this UITableViewCell. For example, in MainStoryboard, you have a UITableViewController subclass called MyTableViewController and have a custom dynamic UITableViewCell called MyTableViewCell with identifier id "MyCell".
If you create your custom UITableViewController like this:
MyTableViewController *myTableViewController = [[MyTableViewController alloc] init];
It will not automatically register your custom tableviewcell for you. You have to manually register it.
But if you use storyboard to instantiate MyTableViewController, like this:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
MyTableViewController *myTableViewController = [storyboard instantiateViewControllerWithIdentifier:#"MyTableViewController"];
Nice thing happens! UITableViewController will automatically register your custom tableview cell that you define in storyboard for you.
In your delegate method "cellForRowAtIndexPath", you can create you table view cell like this :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"MyCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
//Configure your cell here ...
return cell;
}
dequeueReusableCellWithIdentifier will automatically create new cell for you if there is not reusable cell available in the recycling queue.
Then you are done!
I'll just add that Xcode 4.5 includes the new dequeueReusableCellWithIdentifier:forIndexPath:
in its default template code - a potential gotcha for developers expecting the older dequeueReusableCellWithIdentifier: method.
Swift 2.0 solution:
You need to go into your Attribute Inspector and add a name for your cells Identifier:
Then you need to make your identifier match with your dequeue like this:
let cell2 = tableView.dequeueReusableCellWithIdentifier("ButtonCell", forIndexPath: indexPath) as! ButtonCell
Alternatively
If you're working with a nib you may need to register your class in your cellForRowAtIndexPath:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "SwitchCell")
// included for context
let cell = tableView.dequeueReusableCellWithIdentifier("SwitchCell", forIndexPath:indexPath) as! SwitchCell
//... continue
}
Apples's UITableView Class Reference says:
Prior to dequeueing any cells, call this method or the
registerNib:forCellReuseIdentifier: method to tell the table view how
to create new cells. If a cell of the specified type is not currently
in a reuse queue, the table view uses the provided information to
create a new cell object automatically.
If you previously registered a class or nib file with the same reuse
identifier, the class you specify in the cellClass parameter replaces
the old entry. You may specify nil for cellClass if you want to
unregister the class from the specified reuse identifier.
Here's the code from Apples Swift 2.0 framework:
// Beginning in iOS 6, clients can register a nib or class for each cell.
// If all reuse identifiers are registered, use the newer -dequeueReusableCellWithIdentifier:forIndexPath: to guarantee that a cell instance is returned.
// Instances returned from the new dequeue method will also be properly sized when they are returned.
#available(iOS 5.0, *)
func registerNib(nib: UINib?, forCellReuseIdentifier identifier: String)
#available(iOS 6.0, *)
func registerClass(cellClass: AnyClass?, forCellReuseIdentifier identifier: String)
In your storyboard you should set the 'Identifier' of your prototype cell to be the same as your CellReuseIdentifier "Cell". Then you won't get that message or need to call that registerClass: function.
If you are going with Custom Static Cells just comment this method:
//- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
// static NSString *CellIdentifier = #"notificationCell";
// UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
// return cell;
//}
and give the cells an identifier at "Attributes Inspector" in storyboard.
I give you the answer in both Objective C and Swift.Before that I want to say
If we use the dequeueReusableCellWithIdentifier:forIndexPath:,we must register a class or nib file using the registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier: method before calling this method as
Apple Documnetation Says
So we add registerNib:forCellReuseIdentifier: or registerClass:forCellReuseIdentifier:
Once we registered a class for the specified identifier and a new cell must be created, this method initializes the cell by calling its initWithStyle:reuseIdentifier: method. For nib-based cells, this method loads the cell object from the provided nib file. If an existing cell was available for reuse, this method calls the cell’s prepareForReuse method instead.
in viewDidLoad method we should register the cell
Objective C
OPTION 1:
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"cell"];
OPTION 2:
[self.tableView registerNib:[UINib nibWithNibName:#"CustomCell" bundle:nil] forCellReuseIdentifier:#"cell"];
in above code nibWithNibName:#"CustomCell" give your nib name instead of my nib name CustomCell
SWIFT
OPTION 1:
tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "cell")
OPTION 2:
tableView.registerNib(UINib(nibName: "NameInput", bundle: nil), forCellReuseIdentifier: "Cell")
in above code nibName:"NameInput" give your nib name
Working with Swift 3.0:
override func viewDidLoad() {
super.viewDidLoad()
self.myList.register(UINib(nibName: "MyTableViewCell", bundle: nil), forCellReuseIdentifier: "Cell")
}
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = myList.dequeueReusableCell(withIdentifier: "Cell", for: indexPath as IndexPath) as! MyTableViewCell
return cell
}
I spent hours last night working out why my programmatically generated table crashed on [myTable setDataSource:self]; It was OK commenting out and popping up an empty table, but crashed every time I tried to reach the datasource;
I had the delegation set up in the h file: #interface myViewController : UIViewController
I had the data source code in my implementation and still BOOM!, crash every time! THANK YOU to "xxd" (nr 9): adding that line of code solved it for me! In fact I am launching a table from a IBAction button, so here is my full code:
- (IBAction)tapButton:(id)sender {
UIViewController* popoverContent = [[UIViewController alloc]init];
UIView* popoverView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 200, 300)];
popoverView.backgroundColor = [UIColor greenColor];
popoverContent.view = popoverView;
//Add the table
UITableView *table = [[UITableView alloc] initWithFrame:CGRectMake(0, 0, 200, 300) style:UITableViewStylePlain];
// NEXT THE LINE THAT SAVED MY SANITY Without it the program built OK, but crashed when tapping the button!
[table registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
table.delegate=self;
[table setDataSource:self];
[popoverView addSubview:table];
popoverContent.contentSizeForViewInPopover =
CGSizeMake(200, 300);
//create a popover controller
popoverController3 = [[UIPopoverController alloc]
initWithContentViewController:popoverContent];
CGRect popRect = CGRectMake(self.tapButton.frame.origin.x,
self.tapButton.frame.origin.y,
self.tapButton.frame.size.width,
self.tapButton.frame.size.height);
[popoverController3 presentPopoverFromRect:popRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}
#Table view data source in same m file
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
NSLog(#"Sections in table");
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
NSLog(#"Rows in table");
// Return the number of rows in the section.
return myArray.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
NSString *myValue;
//This is just some test array I created:
myValue=[myArray objectAtIndex:indexPath.row];
cell.textLabel.text=myValue;
UIFont *myFont = [ UIFont fontWithName: #"Arial" size: 12.0 ];
cell.textLabel.font = myFont;
return cell;
}
By the way: the button must be linked up with as an IBAction and as a IBOutlet if you want to anchor the popover to it.
UIPopoverController *popoverController3 is declared in the H file directly after #interface between {}
FWIW, I got this same error when I forgot to set the cell identifier in the storyboard. If this is your issue then in the storyboard click the table view cell and set the cell identifier in the attributes editor. Make sure the cell identifier you set here is the same as
static NSString *CellIdentifier = #"YourCellIdenifier";
I had the same issue, was having the same error and for me it worked like this:
[self.tableView registerNib:[UINib nibWithNibName:CELL_NIB_HERE bundle: nil] forCellReuseIdentifier:CELL_IDENTIFIER_HERE];
Maybe it will be usefull for someone else.
I setup everything correctly in the Storyboard and did a clean build but kept getting the error " must register a nib or a class for the identifier or connect a prototype cell in a storyboard"
[self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:#"Cell"];
Corrected the error but i'm still at a loss. I'm not using a 'custom cell', just a view with a tableview embeded. I have declared the viewcontroller as delegate and datasource and made sure the cell identifier matches in file. whats going on here?
This might seem stupid to some people but it got me. I was getting this error and the problem for me was that I was trying to use static cells but then dynamically add more stuff. If you are calling this method your cells need to be dynamic prototypes. Select the cell in storyboard and under the Attributes inspector, the very first thing says 'Content' and you should select dynamic prototypes not static.
Just a supplement of the answers:
There may be a time you set all things right, but you may accidentally add some other UIs in you .xib, like a UIButton:
Just delete the extra UI, it works.
Make sure that the CellIdentifier == identifier of the cell in a storyboard, both names are same. Hope this works for u
In my case, the crash happened when I calleddeselectRowAtIndexPath:
The line was [tableView deselectRowAtIndexPath:indexPath animated:YES];
Changing it to [self.tableView deselectRowAtIndexPath:indexPath animated:YES]; FIXED MY PROBLEM!
Hope this helps anyone
In Swift this problem can be solved by adding the following code in your
viewDidLoad
method.
tableView.registerClass(UITableViewCell.classForKeyedArchiver(), forCellReuseIdentifier: "your_reuse_identifier")
you have to be aware that when using interface builder and creating a Xib (nib) containing one cell that there is also a placeholder created that points to the class that will be used. Meaning, when you place two UITableViewCell in one Xib file you possibly run into the exact same trouble causing an *** Assertion failure .... The placeholder mechanism doesn't work adn will be confused then. Instead placing different placeholders in one Xib read on..
The most easy solution (even if that seems a bit to simple) is to place one Cell at a time in one Xib. IB will create a placeholder for you and all works as expected then. But this then leads directly to one extra line of code, because then you need to load the correct nib/xib asking for the reuseIdentified Cell where it resides in.
So the following example code focuses the use of multiple Cell Indentifiers in one tableview where an Assertion Failure is very common.
// possibly above class implementation
static NSString *firstCellIdentifier = #"firstCellIdentifier";
static NSString *secondCellIdentifier = #"secondCellIdentifier";
// possibly in -(instancetype)init
UINib *firstNib = [UINib nibWithNibName:#"FirstCell" bundle:nil];
[self.tableView registerNib:firstNib forCellReuseIdentifier:firstCellIdentifier];
UINib *secondNib = [UINib nibWithNibName:#"SecondCell" bundle:nil];
[self.tableView registerNib:secondNib forCellReuseIdentifier:secondCellIdentifier];
Another trouble with the use of two CellIdentifier's in one UITableView is that row height and/or section height have to be taken care of. Two cells can have different heights of course.
When registering classes for reuse the code should look different.
The "simple solution" looks also much different when your cells reside inside a Storyboard instead of Xib's. Watch out for the placeholders.
Keep also in mind that interface builder files have version wise variations and need to be set to a version that your targeted OS version supports. Even if you may be lucky that the particular feature you placed in your Xib is not changed since the last IB version and does not throw errors yet. So a Xib made with IB set to be compatible to iOS 13+ but used in a target that is compiled on an earlier version iOS 12.4 will cause also trouble and can end up with Assertion failure.
Ran into this error bc cell re-use identifier was wrong-- a rookie mistake but it happens:
1. Makes SURE cell re-use idenifier has no misspellings or missing letters.
2. Along same line, don't forget capitalization counts.
3. Zeroes are not "O"s (Ohs)
I'm using a custom UITableViewCell. When I try to run my code, I got this exception stack and I can't understand the source of the problem:
terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'invalid nib registered for identifier ((null)) - nib must contain exactly one top level object which must be a UITableViewCell instance'
Please note I am not using Storyboard.
EDIT:
This is my relevant code which cause the problem according to the breakpoint:
[tableviewSupport registerNib:[UINib nibWithNibName:#"HotelCell" bundle:[NSBundle mainBundle]] forCellReuseIdentifier:CustomCellCId];
Another solution:
I had UITableViewCell, but in my XIB there was an extra object, a label which I had misplaced.
So check your XIB carefully to make sure there is only one object in the object table on the left side.
I'm not quite sure what you are trying to do in your provided code. You will unload your nib in tableView:cellForRowAtIndexPath:. You can use the below code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
// Assuming you set a reuse identifier "cellId" in the nib for your table view cell...
HotelCell *cell = (HotelCell *)[tableView dequeueReusableCellWithIdentifier:#"cellId"];
if (!cell) {
// If you didn't get a valid cell reference back, unload a cell from the nib
NSArray *nibArray = [[NSBundle mainBundle] loadNibNamed:#"HotelCell" owner:nil options:nil];
for (id obj in nibArray) {
if ([obj isMemberOfClass:[HotelCell class]]) {
// Assign cell to obj
cell = (HotelCell *)obj;
break;
}
}
}
return cell;
}
Now, based on the error you posted, iOS is expecting a single object in the array, so the for loop may be unnecessary. I've done this by checking if [nibArray count] == 1 and then grabbing the objectAtIndex:0 and assigning it to cell instead of looping, and this works as well. But, if one day Apple decides to stick something else in that nibArray, a for loop protects you against that.
This may not be the answer to the OP's question, but I had the same error with a different solution, so I'll answer this question for the sake of Googlers who come hereafter.
I did have a single UITableViewCell (actually, my own subclass) in my XIB -- so I couldn't understand why it wasn't working.
The key seems to be:
When you've created a XIB file with a single UITableViewCell or subclass (e.g. if you drag on a UITableViewCell from the library on the lower right), Interface Builder shows you an option under the "Table View Cell" section of the Inspector tab.
I usually used to create a UIView and changing its type to my UITableViewCell subclass, so I had never noticed that option.
It is there that you need to type the identifier (as well as in your registerNib:withReuseIdentifer: call).
More frustrating for me when experiencing this was that it didn't crash EVERY time, only the first time. Weird.
In my case I set a property with name class (for eg: #property (strong, nonatomic) IBOutlet UILabel *class) in tableviewcell, this give above mention error , then name "class" is not objective c type, change (class = classabc) resolve above issue.