TouchMoved and wrong screen range? or Bug in iOS?

Question

I found interesting bug in iOS, but trying to belive that i\'m wrong. You have to do 2 things:

1) Create single-view template for iOS

2) Write small function i

Answer 1

I found this from one of Apple's tutorials on a finger-painting program:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    CGRect              bounds = [self bounds];
    UITouch*    touch = [[event touchesForView:self] anyObject];
    firstTouch = YES;
    // Convert touch point from UIView referential to OpenGL one (upside-down flip)
    location = [touch locationInView:self];
    location.y = bounds.size.height - location.y;
}

Looks like you need to convert the touch to OpenGL coordinates to get the result you are expecting. Hope this helps.

Answer 2

Because the status bar is out of limits of the view. And you gets negative values when you touch on status bar.

Try this:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event 
{
    UITouch* touch = [touches anyObject];
    CGPoint point = [touch locationInView:[touch window]];
    NSLog(@"%@", NSStringFromCGPoint(point));
}

Answer 3

The view of root viewController always acts like portrait mode. You should insert a new view inside of the root one. And this new view will acts correctly, will give right size and coordinates according to Apple says.

for example ;

UIView *v = self;
while ([[v superview] superview] != NULL) {
    v = [v superview];
}

UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInView:v];

touchPoint will be the correct one.