iOS Error in getting item from array

[DSchwartz88]

Hey All,

Im having an issue with my program. The following function gets information needed for an HTTPRequest, however, it does not grab the information.

- (NSDictionary*)getSelNewsItem {
NSIndexPath *ip = [postsTable indexPathForSelectedRow];

if(ip == nil) return nil;
else {
return [news objectAtIndex:ip.row];
}

The line that is not working is:

NSIndexPath *ip = [postsTable indexPathForSelectedRow];


for some reason when it goes to grab that it comes back nil, however in the same .m file i use postsTable for other functions and the data comes back fine. Please help!!

Thanks,
Daniel

 

[grimjim]

For starters, I suggest you lose the semicolon at the end of :

if(ip == nil) return nil;

Otherwise the else statement will never be reached...

 

[Ron C]

Yeah, I'm not particularly thrilled with bare statements following if or else because they confuse the reader. My recommendation is to wrap the statement in braces.

Further, I would re-order the test (that is, make the positive one the first one). I'm not much of a Obj-C programmer yet, so if I were to write it like a C/C++ programmer I'd use something more like:

if (ip != nil) { // this would be "if (ip) {" in my C/C++ code
    return [news objectAtIndex:ip.row]; 
} else {
    return nil;
}

Another option is to step through it in the debugger and see what happens. If you're going to do that, I like adding in throw-away locals to both add handy breakpoint places along with easily showing intermediate values. There my recommendation is more like this:

if (ip != nil) { // this would typically be "if (ip) {" in my C/C++ code
    // not sure the type of row or the result of this call, so let's call them
    // "int" and "Thing" respectively.
    int _row = ip.row;
    Thing *_result = [news objectAtIndex: ip.row];
    return _result;
    // Leave this code here, we may want to return to the simpler, more
    // direct version once we're happy with it working as expected.
    // return [news objectAtIndex:ip.row]; 
} else {
    return nil;
}