- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event;
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event;
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
    CGRect rect = CGRectMake(0, 0, self.view.bounds.size.width/2, self.view.bounds.size.height);
    if (CGRectContainsPoint(rect, point)) 
        return [super hitText:point withEvent:event];
    else
        return nil; 
}