- (void)viewDidLoad
{
    [super viewDidLoad];
    NSLog(@"%f", [[self view] bounds].size.width);
}
- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    NSLog(@"%f", [[self view] bounds].size.width);
}
- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];
    NSLog(@"%f", [[self view] bounds].size.width);
}

2015-02-11 14:48:03.274 MyApp[2948:86285] 320.000000
2015-02-11 14:48:03.274 MyApp[2948:86285] 320.000000
2015-02-11 14:48:03.783 MyApp[2948:86285] 320.000000

NSLog(@"%f", [[UIScreen mainScreen] bounds].size.width);

NSLog(@"%f", [[self view] bounds].size.width);

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
    NSLog(@"%f",[[self view] bounds].size.width);

}
-(void) viewWillAppear:(BOOL)animated{
    NSLog(@"%f",[[self view] bounds].size.width);
    [testIndicator startAnimatingInView:self.view];
}

2016-02-17 19:00:47.519 xxxxx[16107:504629] 320.000000
2016-02-17 19:00:47.521 xxxxx[16107:504629] 414.000000

- (void)viewDidLoad {
    NSLog(@"screens = %@", [UIScreen screens]);
    NSLog(@"self.frame= %@", NSStringFromCGRect([[UIScreen mainScreen] bounds]));
    NSLog(@"self.view.frame= %@", NSStringFromCGRect(self.view.frame));
}

2015-02-11 12:45:19.116 Test[1558:87057] screens = (
    "<UIScreen: 0x7ff0b970bcc0; bounds = {{0, 0}, {375, 667}}; mode = <UIScreenMode: 0x7ff0b961b500; size = 750.000000 x 1334.000000>>"
)
2015-02-11 12:45:19.117 Test[1558:87057] self.frame= {{0, 0}, {375, 667}}
2015-02-11 12:45:19.117 Test[1558:87057] self.view.frame= {{0, 0}, {375, 667}}

-(void)viewDidLoad
{
    [NSTimer timerWithTimeInterval:1.0 target:self selector:@selector(getMyFrame) userInfo:nil repeats:NO];
    [super viewDidLoad];
}
-(void)getMyFrame
{
    NSLog(@"%f", [[self view] bounds].size.width);
}

override func viewWillLayoutSubviews() {
    print("view Size: (view.bounds.width)")
}

NSLog(@"Width: %f Height: %f"
      ,[[UIScreen mainScreen] bounds].size.width
      ,[[UIScreen mainScreen] bounds].size.height);