Question

My application has two ViewControllers linked with NavigationController. The First NavigationController has one view with buttons and one view with labels. This view is a circular rotating menu and it represents my home page. The views can rotate with CGAffineTransformMakeRotation – QuartzCore (apparently it’s causing the issue) on touchesMoved:.

I wanted to hide the NavigationBar only in this view, so I used setNavigationBarHidden:YES on ViewWillAppear. Then show the bar on ViewWillDisappear.

On the simulator, everything works as expected until i rotate the first ViewController, when i rotate then click on any button (go to the second ViewController) then click on Back (to go back to my first ViewController), everything will be distorted!.

1. I tried to fix the issue by adding [self.view setBounds:[[UIScreen
   mainScreen]bounds]]; *[self.view setFrame:[[UIScreen
   mainScreen]bounds]];* in ViewDidLoad method or ViweWillAppear,
   the issue remains.
2. I tried to set NavigationBar alpha to 0 in ViewWillAppear and set
   it to 1 on ViewWillDisappear and I tried
   self.navigationController.navigationBar.translucent = YES both
   options didn’t resolve the problem.
3. I tried to set programmatically views, buttons and labels positions
   in ViewWillAppear and it doesn’t resolve the problem.
4. I doubted the animation so I removed it but it hasn’t any effect on the problem.

As a beginner I’m unable to resolve this issue, please help!

ViewController.h (first ViewController)

#import <UIKit/UIKit.h>
#import <QuartzCore/QuartzCore.h>

@interface ViewController : UIViewController

@property (nonatomic, strong) IBOutlet UIView *aView;
@property (nonatomic, strong) IBOutlet UIView *bView;

@property (nonatomic, strong) IBOutlet UIButton *bimg1;
…
@property (strong, nonatomic) IBOutlet UILabel *label1;
…
-(void) rotateTo:(CGFloat)x andY:(CGFloat)y;

@end

ViewController.m

#import "ViewController.h"

@implementation ViewController
@synthesize aView = _aView;
…
@synthesize bimg1 = _bimg1;
…
@synthesize label1 = _label1;
…

static inline double toradians (double degrees) {
return degrees * M_PI/180;
}

-(void)viewDidLoad {
    ![enter image description here][1][super viewDidLoad];
    //Set text font
    [_label1 setFont:[UIFont fontWithName:@"Consolas" size:16]];
…
    [self.view setBounds:[[UIScreen mainScreen]bounds]];
    [self.view setFrame:[[UIScreen mainScreen]bounds]];
}

-(void)viewWillAppear:(BOOL)animated {
    self.navigationController.navigationBar.hidden = YES;
    printf("Aview x: %f     | Aview y: %f \n",self.aView.frame.origin.x, self.aView.frame.origin.y);
    printf("Aview width: %f | Aview height: %f \n",self.aView.frame.size.width,    self.aView.frame.size.height);
}

-(void)viewWillDisappear:(BOOL)animated {
    self.navigationController.navigationBar.hidden = NO;
}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    UITouch *touch = [touches anyObject];
    CGPoint LastTouchPoint = [touch locationInView:self.view];
    CGFloat LasTouchx = LastTouchPoint.x;
    CGFloat LasTouchy = LastTouchPoint.y;

    CGPoint CenterPoint = self.view.center;
    CGFloat x = LasTouchx - CenterPoint.x;
    [self rotateTo:x andY:y];
}

-(void) rotateTo:(CGFloat)x andY:(CGFloat)y {
    CGFloat angle = x/y;
    angle = atan(angle);
    angle = angle * 360/M_PI;
    angle *= 0.0174532925;

    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
    [UIView setAnimationDuration:1];
    self.aView.transform=CGAffineTransformMakeRotation(-angle); 
    self.bView.transform=CGAffineTransformMakeRotation(-angle); 

    self.bimg1.transform=CGAffineTransformMakeRotation(angle);
    self.bimg2.transform=CGAffineTransformMakeRotation(angle);
    self.bimg3.transform=CGAffineTransformMakeRotation(angle);
    self.bimg4.transform=CGAffineTransformMakeRotation(angle);

    self.label1.transform=CGAffineTransformMakeRotation(angle);
    self.label2.transform=CGAffineTransformMakeRotation(angle);
    self.label3.transform=CGAffineTransformMakeRotation(angle);
    self.label4.transform=CGAffineTransformMakeRotation(angle);
    [UIView commitAnimations];
}

- (void)viewDidUnload
{
    [self setBimg1:nil];
    … 
    [self setAView:nil];
    [self setBView:nil];
    [super viewDidUnload];
 }

Answer 1

Yeah, I figured out the problem… The autoresize of the main View was squeezing my subviews when the NavigationController is hidden or not. so i added self.view.autoresizesSubviews = NO; to ViewDidLoad and the problem is fixed.