Question

I have a problem with my application for the iPhone.

It’s a tab based application. In one of the tabs, I have a Table View. I have set it up to load in data from a PLIST.

My problem is that when I try to build and run it, the application either crashes, or stays at a black screen with the error message “Terminating app due to uncaught exception”.

I looked in the console, and found that the error probably laid in this string:

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
 return workouts.count;
}

(error message:)

2010-02-06 21:50:54.733 Mudo[52439:207] *** -[FirstViewController tableView:numberOfRowsInSection:]: unrecognized selector sent to instance 0x39101a0
2010-02-06 21:50:54.735 Mudo[52439:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[FirstViewController tableView:numberOfRowsInSection:]: unrecognized selector sent to instance 0x39101a0'
2010-02-06 21:50:54.736 Mudo[52439:207] Stack: (
    29344859,
    2569487625,
    29726779,
    29296246,
    29148866,
    4413562,
    4420938,
    4419935,
    3136474,
    3076985,
    3118420,
    3106975,
    55857840,
    55857263,
    55855302,
    55854394,
    2780921,
    2804616,
    2787027,
    2814133,
    37441233,
    29129600,
    29125704,
    2780777,
    2818051
)

Building the app does not generate any errors.

Please help me? Thanks 🙂

Answer 1

If you look at the actual text of the exception, 'NSInvalidArgumentException', reason: '*** -[FirstViewController tableView:numberOfRowsInSection:]: unrecognized selector sent to instance 0x39101a0', you can see the root of the problem. Somewhere in your code you’re calling tableView:numberOfRowsInSection: on a FirstViewController, which doesn’t implement that method.

Exceptions are not caught at compile-time, but rather thrown at runtime. You may want to read up on them if you aren’t familiar, as they’re a fairly important part of many programming languages.

http://en.wikipedia.org/wiki/Exception_handling