Objective-C passing data
===

I've done a single-view project that has NewClass.h/.m ViewController.h/.m:

NewClass.h:

    #import <Foundation/Foundation.h>

    @interface NewClass : NSObject
    -(void)String2;
    @end


---------------------------------
NewClass.m
   

   
    #import "NewClass.h"
    @implementation NewClass
    -(void)String2
    {
    NSLog(@"it works");
    }
    @end


----------------------------------
ViewController.h:

    enter code here

    #import <UIKit/UIKit.h>

    @interface ViewController : UIViewController

    @end
-----------------------------------
ViewController.m:

    enter code here

    #import "ViewController.h"
    #import "NewClass.h"

    @interface ViewController ()
    @property (strong) NewClass *obj;
    @end

    @implementation ViewController
    @synthesize obj = _obj;

    - (void)viewDidLoad
    {
    [super viewDidLoad];
	[self.obj String2];
     }

     - (void)viewDidUnload
    {
    [super viewDidUnload];
    
    }

    - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
    {
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
        return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
    } else {
        return YES;
    }
    }
    @end

The question is that program doesn't work. I don't see "it works". ViewController sees a method of obj, but NewClass doesn't pass anything. Please can anybody help me?????? 