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iOS

Posted by Gregg Mojica
Gregg Mojica
11,506 Points

PFQuery

Update: likedKey's values are numbers.

Hi Guys, So I'm working on a project.....I need to be able to query Parse.com for a class and find that class's list of values.

I have a column called likedKey and I want to be able to display all the likedKey's values into a label named likedLabel.

So far I've got this much..

  PFQuery *query = [PFQuery queryWithClassName:@"myClassName"];
  [query whereKey:@"likedKey" ?????];
  cell.likedLabel.text = [NSString stringWithFormat:@"%@", query];

But I'm not sure what to do with that second line. Could anyone offer assistance? Stone Preston Thanks!!

1 Answer

Stone Preston
Stone Preston
42,016 Points

you want to query your backend in viewDidAppear, not in cellForRowAtIndexPath. you want all the objects in the class so you shouldnt need any constraints on your query:

- (void)viewWillAppear:(BOOL)animated {

[super viewWillAppear:animated];


//you dont need to set any contraints on your query, you want all the object in the class. the query below gets all the objects in the class
//if you want more than 100 you need to set a limit on the objects
  PFQuery *query = [PFQuery queryWithClassName:@"myClassName"];
  [query setLimit: 1000];
[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
    if (!error) {

        //store the objects in  an array property
        self.objects = objects;
    } else {
        // Log details of the failure
        NSLog(@"Error: %@ %@", error, [error userInfo]);
    }

}];


}

then in cellForRowAtIndexPath set the label value:

//assuming your likeCount is an NSNumber
NSString likeCount = [[[self.objects objectAtIndex:indexPath.row] valueForKey:@"likedKey"] stringValue];
cell.likedLabel.text = likeCount;
Gregg Mojica
Gregg Mojica
11,506 Points

Hi Stone, Thanks for the quick reply!

My problem is that when I implement
self.objects = objects; I am given an error: property "objects" not found... is this a property I need to implement in the .h?

Also, what do you mean by "assuming your likeCount" is an NSNumber?
From the code you gave me above, it looks like likeCount is a NSString you declared above? A I mentioned above, I have a column in parse called likedKey that is a number.

I sincerly thank you for your help!

Stone Preston
Stone Preston
42,016 Points

Yes you would need to add that property. As For the nsnumber If you look at the method calls you will see I used the stringValue method of NSNumber to convert the value stored in likeKey to a string

Gregg Mojica
Gregg Mojica
11,506 Points

Hi Stone! You're amazing! I really appreciate it...everything's working now! :)

Gregg Mojica
Gregg Mojica
11,506 Points

Hey Stone, can I pick your brain for one more sec? I want the user to be able to press a button and then add the number 1 to the current likedKey value in Parse. I set up an IBAction for the button and I understand the general gist of how to do it - Add one, save it in parse, then reload the tableview and update the label. But I'm not entirely sure how to add 1 (and save it in parse) each time a user presses that button. Any ideas? Again, thanks a ton for your help!