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iosobjective-cuiscrollviewpositioncontentoffset

Get current position of UIScrollView


I'm coming from Android and i'm getting a lot of headache in IOS. I need to make a scroll menu like a movie credits. I used the code below:

rol = scroll_view.contentOffset.y;
timer = [NSTimer scheduledTimerWithTimeInterval:.02 target:self selector:@selector(timer_rol) userInfo:nil repeats:YES];

-(void)timer_rol{
    [scroll_view setContentOffset:CGPointMake(0,rol) animated:YES];
rol++;
}

This code works fine, but when the user interact scrolling up or down, the view return to position before (value of rol). The question is, how can i get the current content position after scrolling

i already tried these codes, but no one works:

CGPoint point = [scroll_view contentOffset];
rol = r.y  +1;

-(void) handleGesture:(UIGestureRecognizer *) sender{}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {}
-(void)scrollViewDidScroll:(UIScrollView *)scrollView {}

Anyone can help me?


Solution

  • The solution was:

    //Update the value of rol
    - (void)scrollViewDidScroll:(UIScrollView *)scrollView{
        rol_y = scroll_webView.contentOffset.y;
        rol_x = scroll_webView.contentOffset.x;
    }
    
    //Call the timer
    timer = [NSTimer scheduledTimerWithTimeInterval:.25 target:self selector:@selector(timer_rol) userInfo:nil repeats:YES];
    
    //Scroll the view (Works when i set animated:NO)
    - (void)timer_rol{
        [scroll_webView setContentOffset:CGPointMake(rol_x, rol_y + 1) animated:NO];
    }