Parse login not working properly - ios

Question

I am using this code from Parse:
[PFUser logInWithUsernameInBackground:namerL password:passerL
block:^(PFUser *user, NSError *error) {
if (user) {
[self performSegueWithIdentifier:#"signinToInbox" sender:self];
} else {
NSLog(#"%#",error);
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Login Failed." message:#"Invalid Username and/or Password." delegate:self cancelButtonTitle:#"Okay" otherButtonTitles:nil];
[alert show];
}
}];
Whenever I click on the sign in button without typing in anything, it doesn't log any errors. I need it to count it as an error if there is no such user and or if the password is correct. But even if the account details are not correct, it is still going to the segue.
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { I believe that it's calling the segue because it is still in didSelectRowAtIndexPath. I just don't know how to stop it from calling the segue that's connected it (by default).

Answer 1

Maybe this problem isn't about parse login at all. From the comments, it seems to be about segues attached to table view cells.
If you want to perform a segue conditionally, it shouldn't be attached directly to the table view cell. Instead draw the segue between view controllers in IB (ctrl-drag from the view controller's status bar to the destination vc). Give that segue a name, like "goodLogin", then perform it manually upon a condition.
So if you only want to segue when a login succeeds ...
// parse login
if (!error) {
[self performSegueWithIdentifier:#"goodLogin"];
} else {
// don't perform a segue. Stay here and change ui to indicate an error
}

Answer 2

This is the code I use:
[PFUser logInWithUsernameInBackground:username password:password block:^(PFUser *user, NSError *error) {
if(!error){
[self loggedInSuccessfully];
} else {
[self loginFailedWithError:error];
}
}];
When doing any API call, I would always check the error variable because if it exists then you know the method failed.
EDIT
From our discussion it appears that you are having problems with your UITableView performing the segue when you click on a cell.
It is possible to disable a segue by returning NO from the shouldPerformSegueWithIdentifier method
- (BOOL)shouldPerformSegueWithIdentifier:(NSString *)identifier sender:(id)sender
{
if([identifier isEqualToString:#"signinToInbox"]){
return YES;
}
return NO;
}
This will disable all segues on the UIViewController apart from your signinToInbox
However, I believe you may have your UIStoyboard set up incorrectly, there shouldn't be the default segue enabled. You should only need to perform the segue in the code after you have called the login function. Therefore in the storyboard you should be using the custom segue option.
If you have a segue set up already on the UIStoryboard you should be able to click on it and in the Attributes inspector panel change the drop down from model to custom

Answer 3

It seems you have problems with your segues and table views. Try the following in Xcode 6.
First delete your current segue.
Ctrl + drag as shown:
After that, choose the action segue you want (push, modal or custom). Then make sure the identifier matches the one in the code.
Now simply make the following changes in the code
[PFUser logInWithUsernameInBackground:namerL password:passerL block:^(PFUser *user, NSError *error) {
if (!error) {
[self performSegueWithIdentifier:#"signinToInbox" sender:self];
} else {
NSLog(#"Error logging in: %#",error);
[[[UIAlertView alloc] initWithTitle:#"Login Failed" message:#"In valid username and/or password" delegate:self cancelButtonTitle:#"OK" otherButtonTitles:nil] show];
}
}];