title: Validating UITextField and Display an UIAlertView if error
body: <p>I would like to validate UITextField and display an UIAlertView if there is an error.</p>
  
  <p>Previously I used the code below. It works perfectly with 2 UITexfields but with many UITextfield it's not possible. </p>
  
  <p>Any tips how to display an UIAlertView to validate my UITexfields ?</p>
  
  <pre><code>- (void)processFieldEntries {
  
      NSString *usernameString = usernameField.text;
      NSString *passwordString = passwordField.text;
      NSString *firstNameString = firstNameField.text;
      NSString *nameString = nameField.text;
      NSString *cityString = cityField.text;
  
      NSString *errorText = @"Enter";
      NSString *usernameBlankText = @" a username";
      NSString *passwordBlankText = @" a password";
      NSString *prenomBlankText = @" a firstname";
      NSString *nomBlankText = @" a name";
      NSString *joinText = @", ";
  
      BOOL textError = NO;
  
      if (identifiantString.length == 0 || motDePasseString.length == 0 || prenomString.length == 0 || nomString.length == 0 || idPoubelle.length == 0) {
          textError = YES;
  
          if (usernameString.length == 0) {
              errorText = [errorText stringByAppendingString:usernameBlankText];
          }
  
          if (usernameString.length == 0 || passwordString.length == 0) {
              if (usernameString.length == 0) { 
                  errorText = [errorText stringByAppendingString:joinText];
              }
              errorText = [errorText stringByAppendingString:passwordBlankText];
          }
      } 
  
      if (textError) {
          UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:errorText message:nil delegate:self cancelButtonTitle:nil otherButtonTitles:@"Ok", nil];
          [alertView show];
          return;
      }
  }
  </code></pre>