Button won't log textfield values - ios

Question

So for my iOS app, if I delete the textfields and the code which grabs the text field values, the button works--in that it presents the indicated view controller..
But when I add these textfields and try to get the button to also Log their values, the button no longer works in that I push the button and nothing happens.
It's also worth mentioning that the code which creates these textfields is littered with "local declaration of "X" hides instance variable" warnings.. but i hear that's not too important (?)
Here's what's in the .h file:
#interface RootViewController : UIViewController
#property (nonatomic, retain) IBOutlet UITextField *usernameTextfield;
#property (nonatomic, retain) IBOutlet UITextField *passwordTextfield;
- (IBAction)buttonClicked: (id)sender;
#end
And in the .m file:
#import "RootViewController.h"
#import "chooseFeedItemViewController.h"
#interface RootViewController ()
#end
#implementation RootViewController
#synthesize passwordTextfield;
#synthesize usernameTextfield;
- (void)viewDidLoad {
[super viewDidLoad];
UIView* v = self.view;
v.backgroundColor = [UIColor whiteColor];
//load Feed View button
CGRect buttonFrame = CGRectMake(177, 250, 100, 100);
UIButton *button = [[UIButton alloc] initWithFrame: buttonFrame];
[button setTitle: #"submit" forState: UIControlStateNormal];
[button setTitleColor: [UIColor blueColor] forState: UIControlStateNormal];
[button addTarget: self
action: #selector(buttonClicked:)
forControlEvents: UIControlEventTouchDown];
[v addSubview: button];
//username textfield
IBOutlet UITextField *usernameTextfield = [[UITextField alloc] initWithFrame:CGRectMake(45, 30, 200, 40)];
usernameTextfield.textColor = [UIColor colorWithRed:0/256.0 green:84/256.0 blue:129/256.0 alpha:1.0];
usernameTextfield.font = [UIFont fontWithName:#"Helvetica-Bold" size:25];
usernameTextfield.backgroundColor=[UIColor whiteColor];
usernameTextfield.placeholder=#"create username";
//password textfield
IBOutlet UITextField *passwordTextfield = [[UITextField alloc] initWithFrame:CGRectMake(45, usernameTextfield.frame.origin.y+75, 200, 40)];
passwordTextfield.textColor = [UIColor colorWithRed:0/256.0 green:84/256.0 blue:129/256.0 alpha:1.0];
passwordTextfield.font = [UIFont fontWithName:#"Helvetica-Bold" size:25];
passwordTextfield.backgroundColor=[UIColor clearColor];
passwordTextfield.placeholder=#"create password";
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(15, 80, 400, 400)];
[view addSubview:usernameTextfield];
[view addSubview:passwordTextfield];
[v addSubview:view];
}
-(IBAction) buttonClicked:(id)sender {
NSString *password = [passwordTextfield text];
NSString *username = [usernameTextfield text];
NSLog(#"username = %# and password = %#", username, password);
[self presentViewController:[ChooseFeedItemViewController new]
animated:YES completion:nil];
}
There's more to the .m file but it's irrelevant, i think

Answer 1

alloc init give you brand spanking new objects, NOT references to your existing ones. Use self.usernameTextField to access your existing object.

Answer 2

You are in completely over your head.
Do not create new text fields. Set up your text fields in Interface Builder (IB), and control-drag from your IB fields into the header of your program to create IBOutlets. Then use those IBOutlets in your code.
It does matter, and matter a great deal, that you are getting "local declaration of "X" hides instance variable" warnings.
The problem is that you have instance variables for your text fields, and then you have code that creates an unrelated set of text fields and installs them in your form. If you also created text fields in IB, then you've got duplicates of each text field, but only one is connected to your IBOutlet instance variables. If you never created the text fields in IB, then your outlets point to nil.
You should stop, find a good book or set of video tutorials on Objective C and/or iOS development, and go through the exercises to learn the basics. Your lack of understanding is more than a few forum questions is going to fix.