try and catch is not handling exception in iphone

Question

i am using the following code to catch an error when ind.row is not a valid value or sometimes it becomes nil

@try {
        if(ind.row<[[treeNode flattenElements] count])
        {
            [self.mTableView scrollToRowAtIndexPath:ind atScrollPosition:UITableViewScrollPositionTop animated:YES];
        }


    }
    @catch (NSException *e) {
        NSLog(@"%@",e);

    }

but when this code executes sometimes this error is occuring

Assertion failure in -[NSIndexPath row], /SourceCache/UIKit_Sim/UIKit-1262.60.3/UITableViewSupport.m:1948`

what may be the reason for this error and why exception is not being handled

I don't know about iphone, but, I think you should also add `@catch (Exception *ee) {` `NSLog(@"%@",ee);}` — Fahim Parkar, Jan 16 '12 at 07:35
You shouldn't be trying to catch an assertion failure to begin with. Your `NSIndexPath` was created incorrectly. — Lily Ballard, Jan 16 '12 at 07:36
@KevinBallard actually what i am doing is in textfielddidbeginediting i pass the index of that cell to a ivar called ind by ind=[[self.mTableView indexPathForCell:(UITableViewCell*)textField.superview] retain]; then in the keyboardwasshown method,i use the above code for the textfield to scroll up when keyboard appears,but this is giving errors like this — sujith1406, Jan 16 '12 at 07:42

score 3 · Answer 1 · answered Jan 16 '12 at 08:02

3

Assertions in iOS don't throw exceptions, so you can't catch them.

You are going to need to figure out what's wrong with your call to -row. My first guess would be that "ind" is already freed or something.

answered Jan 16 '12 at 08:02

StilesCrisis

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score 1 · Answer 2 · answered Jan 16 '12 at 08:07

1

You'll have to check the index, generate and raise an exception on you own:NSException Class Reference

+ (void)raise:(NSString *)name format:(NSString *)format, ...

answered Jan 16 '12 at 08:07

A-Live

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score 1 · Accepted Answer · answered Jan 16 '12 at 08:18

1

actually it was already catching the exceptions...i had set the flag stop on objc exceptions.when i removed that it catching the exceptions.... as pointed out by @stilesCrisis the ind value was null at the time of this exception..sorry for the trble

answered Jan 16 '12 at 08:18

sujith1406

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try and catch is not handling exception in iphone

3 Answers3