单击详细信息页面上的自定义后退按钮可崩溃的应用程序（仅在iOS8中）

Question

I have a app with following structure

first i have a button in my home page when i click that it will open a new UITableView and display list of "Main Programs" When a user click on any of those will open another view controller and display all "Sub Programs" in that user can select each sub programs to see the details.

All these are working fine till iOS 7 versions. Recently i upgraded device to iOS 8 (iPad and iPhone) then i run the same code and when we return from "Sub Program Detail " page to "Sub Program" Page App is crashing. There is no log message .Only am getting this one Please help ,The back button is working fine but something in that previous tableview controller not working .

i tried to do instrumentation then i got following message http://postimg.org/image/ytezux0m9/

Then i tried to debug it but i couldnt find anything wrong there (every value was correct) and then i tried to add "tableview relaod data" to ViewWillAppear () .And then i got a crash log like this

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UISearchDisplayController numberOfSectionsInTableView:]: unrecognized selector sent to instance 0x124e6e7a0'
*** First throw call stack:
(0x1872ee084 0x1978d40e4 0x1872f5094 0x1872f1e48 0x1871f708c 0x18be51d38 0x18bb49480 0x18bb491f4 0x18bb4fe74 0x18ba6d140 0x18ba8e4c8 0x18ba6ce58 0x18ba6ce58 0x18ba8e4c8 0x18ba6ce58 0x18ba6ce58 0x18ba6ce58 0x18ba6c528 0x18ba6c408 0x18ba77ea4 0x18bc5ab18 0x18ba7e77c 0x18bc5a3a4 0x18bc14278 0x18bb24f40 0x18bb24d0c 0x18bb24c8c 0x18ba6d874 0x18b3c5d58 0x18b3c0944 0x18b3c07e8 0x18b3bffe8 0x18b3bfd6c 0x18ba6f790 0x1872a6324 0x1872a55c8 0x1872a3678 0x1871d1664 0x1903135a4 0x18bad64f8 0x1000a4c80 0x197f42a08)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb) 

Just now i run then i got this in my log

-[UITextFieldLabel numberOfSectionsInTableView:]: unrecognized selector sent to instance 0x12fe79f70

UPDATES :

one more thing like when i going forward my if condition is true and when i click back button its geting false and execute else part for - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section method code is here http://postimg.org/image/kikrbltj1/

Answer 1

I think the reason for the crash is that when you click on the back button from detail, popViewController is called twice. The navigation controller firstly pops the "Sub Program Detail" page, and then immediately pops the "Sub Program" Page. In the "Sub Program" viewWillAppear method, a setupContainer method is executed and loading some FKRSearchBarTableViewController which has table to be filled.

So when the navigation controller firstly pop the "Sub Program Detail" Page, app goes to the "Sub Program" page's viewWillAppear method, where setupContainer is executed and tables are loading data, at the same time, "Sub Program" page is poped out."Sub Program" is dealloc'ed, So are the FKRSearchBarTableViewControllers, which are busy loading their tableViews. That's why message sent to dealloc'ed object.

You can move the line [self setupContainer] in DAViewController from viewWillAppear to the end of viewDidLoad , and remove the lines

if ([self.navigationController.viewControllers indexOfObject:self]==NSNotFound) {
    // Navigation button was pressed. Do some stuff
    [self.navigationController popViewControllerAnimated:YES];
}

from viewWillDisappear in THProgramDetailsViewController.m .

Since in backBtnClick method, pop action has already been executed.