How to fill a textfield with appropiate username based on avatar selection - ios

Question

I have constructed the following method fetchLastFiveLogins and the method successfully adds the users avatar to the _avatarButton. However, when a user taps the avatar it calls the fillUserName method. That part is working, but I can't figure out how to fill the _textfieldUsername with the username associated with the avatar. Below is a snippet of the fetchLastFiveLogins method.
// sort / filter "results" to display the last five "lastLogin(s)"
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:#"lastLogin" ascending:NO];
NSArray *sortDescriptors = [NSArray arrayWithObjects:sortDescriptor, nil];
[request setFetchLimit:5];
[request setSortDescriptors:sortDescriptors];
// fetch records and handle error
NSError *error;
NSArray *results = [_managedObjectContext executeFetchRequest:request error:&error];
if (!results) {
// handle error
// also if there is login data handle error so app doesn't crash
}
Account *anAccount;
// create a stock image
UIImage *btnImage = [UIImage imageNamed:#"HomeBrewPoster1.jpg"];
NSMutableArray *avatars = [NSMutableArray arrayWithCapacity:5];
for ( anAccount in results) {
NSLog(#"results%#",anAccount.lastLogin);
if(anAccount.lastLogin) {
NSLog(#"anAccount.lastLogin = %#, by:%#",anAccount.lastLogin,anAccount.username);
if (anAccount.avatar != nil) {
UIImage *avatarImg = [UIImage imageWithData:anAccount.avatar ];
[avatars addObject:avatarImg];
}
else {
[avatars addObject:btnImage];
}
}
}
NSLog(#"avatars array%lu",(unsigned long)avatars.count);
for ( NSInteger i = 0; i < 4; i++) {
// Check that we have enough logins
if (i < results.count) {
NSLog(#"avatars =%#",avatars[i]);
CGFloat staticX = 0;
CGFloat staticWidth = 80;
CGFloat staticHeight = 80;
CGFloat staticPadding = 5;
_avatarButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
// the last two values control the size of the button
_avatarButton.frame = CGRectMake(0, 0, 80, 80);
[_avatarButton setFrame:CGRectMake((staticX + (i * (staticHeight + staticPadding))),5,staticWidth,staticHeight)];
// make corners round
_avatarButton.layer.cornerRadius = 40; // value varies -- // 35 yields a pretty good circle.
_avatarButton.clipsToBounds = YES;
// assign method / action to button
[_avatarButton addTarget:self action:#selector(fillUserName) forControlEvents:UIControlEventTouchDown];
[_avatarButton setBackgroundImage:[avatars objectAtIndex:i] forState:UIControlStateNormal];
NSLog(#"avatarImage = %#",[_avatarButton backgroundImageForState:UIControlStateNormal]);
[_avatarScroll addSubview:_avatarButton];
}
}
}

Answer 1

Step 1: Make the fillUserName method take the parameter fillUserName:(id) sender, so that the method will be passed the button that was pressed. You'll want to tweak the addTarget so that it uses #selector(fillUserName:) (with the colon at the end).
Step 2: You'll need to be able to distinguish which of the buttons was pressed. Often people use the tag property of UIButton (and other controls) to distinguish the buttons. If you set the tag to be the array index of the result, then the button with tag 0 is the 0th entry in your results array. See this question: How do i set and get UIButtons' tag? for some code samples.
Step 3: Ensure that you've held on to references to the results array, so that you can access it from the fillUserName: method.
Update: As I mention in my comment, below, a solution that makes use of blocks seems like a much better solution, and some folks have written some nice code to enable that.