顺利隐藏的导航栏

Question

如何在不调整视图框架（或tableView）大小的情况下执行此操作？ 我使用此代码，并调整了视图的大小，然后向下/向上滚动，使用代码，而不是情节提要

 - (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
 {
if ([gestureRecognizer class] == [UIPanGestureRecognizer class])
{
    UIPanGestureRecognizer *panGestureRec = (UIPanGestureRecognizer *)gestureRecognizer;
    CGPoint distance = [panGestureRec translationInView:self.tableView];

    if (distance.y > 0 || distance.y < 0)
    {
        if (distance.y > 0) // down
        {
            //NSLog(@"user swiped down");
            [self.navigationController setNavigationBarHidden:YES animated:YES];

        } else if (distance.y < 0) //up
        {
            //NSLog(@"user swiped up");
            [self.navigationController setNavigationBarHidden:NO animated:YES];
        }

        return NO;
    } else {
        return YES;
    }
}
return YES;

}

Answer 1

试试这个代码。 这将提供平滑的动画（使用的UIView Animation属性）

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
 {
if ([gestureRecognizer class] == [UIPanGestureRecognizer class])
{

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:2];

    UIPanGestureRecognizer *panGestureRec = (UIPanGestureRecognizer *)gestureRecognizer;
    CGPoint distance = [panGestureRec translationInView:self.tableView];

    if (distance.y > 0 || distance.y < 0)
    {
        if (distance.y > 0) // down
        {
            //NSLog(@"user swiped down");
            [self.navigationController setNavigationBarHidden:YES animated:YES];

        } else if (distance.y < 0) //up
        {
            //NSLog(@"user swiped up");
            [self.navigationController setNavigationBarHidden:NO animated:YES];
        }

        return NO;
    } else {
        return YES;
    }

   [UIView commitAnimations];
}
return YES;