UITableView Crashes when scrolling - iphone

Question

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
NSLog(#"Returning num sections");
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSLog(#"Returning num rows");
return 5;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSLog(#"Trying to return cell");
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell =[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier] ;
}
cell.textLabel.text = #"Hello";
NSLog(#"Returning cell");
return cell;
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSLog(#"Selected row");
}
- (void)viewDidLoad
{
[super viewDidLoad];
m_titleTable = [[UITableView alloc] init] ;
m_titleTable.dataSource = self;
m_titleTable.delegate = self;
m_titleTable.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
[self.view addSubview:m_titleTable];
// Do any additional setup after loading the view from its nib.
}
-(void)titleAction:(id)sender{
NSLog(#"Calling");
UIViewController* popoverContent = [[UIViewController alloc]
init];
TitleViewController *popoverView = [[TitleViewController alloc]initWithNibName:#"TitleViewController" bundle:nil];
popoverContent.view = popoverView.view;
//resize the popover view shown
//in the current view to the view's size
popoverContent.contentSizeForViewInPopover = CGSizeMake(150, 150);
//create a popover controller
self->popoverController = [[UIPopoverController alloc]
initWithContentViewController:popoverContent];
//present the popover view non-modal with a
//refrence to the button pressed within the current view
[self->popoverController presentPopoverFromRect:btn_title.frame
inView:self.view
permittedArrowDirections:UIPopoverArrowDirectionUp
animated:YES];
}
The tableview Crash error message
[__NSCFType tableView:cellForRowAtIndexPath:]: unrecognized selector sent to instance 0x6e7dca0
2012-08-28 14:17:10.539 Demo[2790:f803] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFType tableView:cellForRowAtIndexPath:]: unrecognized selector sent to instance 0x6e7dca0'

Answer 1

Your problem is that your view controller is being deallocated. You shouldn't be doing something like this:
UIViewController* popoverContent = [[UIViewController alloc]
init];
TitleViewController *popoverView = [[TitleViewController alloc]initWithNibName:#"TitleViewController" bundle:nil];
popoverContent.view = popoverView.view;
Assuming you are using ARC, your popoverView object will be deallocated. Also this is just incorrect. You should almost never instantiate a UIViewController, and definitely never assign one view controller's view instance to another ones!
Here's how I'd rewrite your titleAction: method:
TitleViewController *titleViewController = [[TitleViewController alloc]initWithNibName:#"TitleViewController" bundle:nil];
//resize the popover view shown
//in the current view to the view's size
popoverContent.contentSizeForViewInPopover = CGSizeMake(150, 150);
//create a popover controller
self.popoverController = [[UIPopoverController alloc]
initWithContentViewController:titleViewController];
//present the popover view non-modal with a
//refrence to the button pressed within the current view
[self.popoverController presentPopoverFromRect:btn_title.frame
inView:self.view
permittedArrowDirections:UIPopoverArrowDirectionUp
animated:YES];
The UIPopoverController, at least, should keep a strong reference to the titleViewController and prevent it from being deallocated.
PS I changed your "self->popoverController" to self.popoverController as the -> is not really correct for what you are trying to do. Dot notation makes explicit that you are setting a property on an object.

Answer 2

in viewDidLoad you allocates and initiates a UITableView and connect it to self. You don't have a UITableView? defined and connect in the nib? Without seeing your whole project my guess is that you have UITableViews - this is a problem but not necessarily the crash problem. Did you inherit from UITableViewController as base class?