ObjC将文本文件行添加到PickerView

Question

I have this code here, which I'm getting a SIGBRT error on runtime. I'm trying to get every line in a text file and add each line into the PickerView, what am I doing wrong?

 NSString* path = [[NSBundle mainBundle] pathForResource:@"Documents/Recent Images"
                                                 ofType:@"txt"];


NSString* content = [NSString stringWithContentsOfFile:path
                                              encoding:NSUTF8StringEncoding
                                                 error:NULL];
_imageURLs = @[content, @"Image Two"];

I'm getting the error on the

_imageURLs = @[content, @"Image Two"];

Actual error:

2014-09-21 21:04:44.369 app[22995:60b] * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '* -[__NSPlaceholderArray initWithObjects:count:]: attempt to insert nil object from objects[0]'

Answer 1

what am I doing wrong?

For any of a number of possible reasons, content is nil . Trying to create the array _imageURLs fails because the first value in the array is nil , and NSArrays cannot contain nil elements.

The first thing you should do is set a breakpoint and confirm for yourself that content really is nil.

The second thing you should do is to add a check that ensures that you won't try to create the array if content is nil:

if (content) {
    _imageURLs = @[content, @"Image Two"];
}

The third thing that you should do is to figure out why the string you expect isn't being created. It could be that the path you've provided is wrong. Are you sure that there's a directory in your bundle named Documents ? Are you sure the file you're looking for exists there? Does it contain data that can be read into a string? Using the error parameter in your -stringWithContentsOfFile:... call will help -- that's what it's there for.