UIScrollView is not scrolling in UiView - ios

Question

when I scroll on UIScrollView that not scrolling . Also I am setting scrollview's contentSize.
When I show one other subView and after when I show my view , it's scrolling.
You can see what is problem on this video . How can I solve this problem?
myViewController.h file
#import <UIKit/UIKit.h>
#interface myViewController : UIViewController
#property(nonatomic,retain)UIView * rightTabView;
#property(nonatomic,retain)UIView * leftTabView;
#property(nonatomic,retain)UIView * middleTabView;
#property(nonatomic,retain)UIScrollView *myscrollview;
#end
myViewController.m file
- (void)viewDidLoad
{
// Do any additional setup after loading the view from its nib.
[super viewDidLoad];
//create Tab views and addSubview
CGFloat barHeight=58;
self.rightTabView=[[UIView alloc] initWithFrame:CGRectMake(0, barHeight+55,self.view.bounds.size.width,self.view.bounds.size.height-barHeight-55)];
[self.view addSubview:self.rightTabView];
self.leftTabView=[[UIView alloc] initWithFrame:CGRectMake(0, barHeight+5,self.view.bounds.size.width,self.view.bounds.size.height-barHeight-55)];
self.leftTabView.backgroundColor=[UIColor redColor];
[self.view addSubview:self.leftTabView];
self.middleTabView=[[UIView alloc] initWithFrame:CGRectMake(0, barHeight+55,self.view.bounds.size.width,self.view.bounds.size.height-barHeight-55)];
[self.view addSubview:self.middleTabView];
//add Subview to leftTabView
myscrollview=[[UIScrollView alloc]initWithFrame:CGRectMake(10, 10,300, 340)];
myscrollview.userInteractionEnabled=YES;
myscrollview.backgroundColor = [UIColor greenColor];
myscrollview.delegate = self;
[self.leftTabView addSubview:myscrollview];
myscrollview.contentSize = CGSizeMake(2000, 2000);
}

Answer 1

It looks like your middleTabView is obscuring your leftTabView (which is the superview of your scrollview). Either bring the leftTabView to the top of the view hierarchy:
[self.leftTabView.superview bringSubViewToFront:self.leftTabView];
or disable user interactions or visibility of your middleTabView (or add the leftTabView last).