/// <summary>
/// Fired when one of the lists are scrolling to the bottom.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void List_OnListEndDetectedEvent(object sender, OnListEndDetected e)
{
// NOTE!!!
// This is a very hot code path, so anything done here should be really quick!
// Get the post
Post post = ((Post)((FrameworkElement)sender).DataContext);
// Make sure the margin is normal.
if(post.FlipViewStickyHeaderMargin.Top != 0)
{
// If the margin is not 0 we are playing our render tick. If the sticky header
// is always set to collapsed it actually never loads or render until we set it to
// visible while we are scrolling which makes it 'pop' in with a delay. To avoid this
// it defaults visible but way off the screen, this makes it load and render so it is ready
// when we set it visible. Here is is safe to restore it to the normal state.
post.FlipViewStickyHeaderVis = Visibility.Collapsed;
post.FlipViewStickyHeaderMargin = new Thickness(0, 0, 0, 0);
}
// Show or hide the scroll bar depending if we have gotten to comments yet or not.
post.VerticalScrollBarVisibility = e.ListScrollTotalDistance > 60 ? ScrollBarVisibility.Auto : ScrollBarVisibility.Hidden;
// Find the header size for this post
int currentScrollAera = GetCurrentScrollArea(post);
// This will return -1 if we can't get this yet, so just get out of here.
if(currentScrollAera == -1)
{
return;
}
// Get the height of the current post header
double currentPostHeaderSize = 0;
lock (m_flipViewStoryHeaders)
{
foreach (Grid flipHeader in m_flipViewStoryHeaders)
{
Post headerPost = (Post)(flipHeader.DataContext);
if (headerPost != null && headerPost.Id.Equals(post.Id))
{
currentPostHeaderSize = flipHeader.ActualHeight;
break;
}
}
}
// Use the header size and the control size to figure out if we should show the static header.
bool showHeader = e.ListScrollTotalDistance > currentScrollAera - currentPostHeaderSize;
post.FlipViewStickyHeaderVis = showHeader ? Visibility.Visible : Visibility.Collapsed;
// If we have a differed header update and we are near the top (not showing the header)
// do the update now. For a full story see the comment on m_hasDeferredHeaderSizeUpdate
if (m_hasDeferredHeaderSizeUpdate && !showHeader)
{
SetHeaderSizes();
}
// Update the last known scroll pos
m_lastKnownScrollOffset = (int)e.ListScrollTotalDistance;
// Hide the tip box if needed.
HideCommentScrollTipIfNeeded();
// Do the rest of this work on a background thread
Task.Run(() =>
{
FlipViewPostCommentManager manager = null;
// Get the comment manager for this post
lock (m_commentManagers)
{
foreach (FlipViewPostCommentManager search in m_commentManagers)
{
if (search.Post.Id.Equals(post.Id))
{
// When found, request more posts
manager = search;
break;
}
}
}
// Make the call if we found one
if(manager != null)
{
manager.RequestMorePosts();
}
});
}
/// <summary>
/// Fired when one of the lists are scrolling to the bottom.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void List_OnListEndDetectedEvent(object sender, OnListEndDetected e)
{
// NOTE!!!
// This is a very hot code path, so anything done here should be really quick!
// Get the post
Post post = ((Post)((FrameworkElement)sender).DataContext);
// Show or hide the scroll bar depending if we have gotten to comments yet or not.
post.VerticalScrollBarVisibility = e.ListScrollTotalDistance > 60 ? ScrollBarVisibility.Auto : ScrollBarVisibility.Hidden;
// Find the header size for this post
int currentScrollAera = GetCurrentScrollArea(post);
// Get the height of the current post header
double currentPostHeaderSize = 0;
lock (m_flipViewStoryHeaders)
{
foreach (Grid flipHeader in m_flipViewStoryHeaders)
{
Post headerPost = (Post)(flipHeader.DataContext);
if (headerPost != null && headerPost.Id.Equals(post.Id))
{
currentPostHeaderSize = flipHeader.ActualHeight;
break;
}
}
}
// Use the header size and the control size to figure out if we should show the static header.
bool showHeader = e.ListScrollTotalDistance > currentScrollAera - currentPostHeaderSize;
post.FlipViewStickyHeaderVis = showHeader ? Visibility.Visible : Visibility.Collapsed;
// If we have a differed header update and we are near the top (not showing the header)
// do the update now. For a full story see the comment on m_hasDeferredHeaderSizeUpdate
if (m_hasDeferredHeaderSizeUpdate && !showHeader)
{
SetHeaderSizes();
}
// Update the last known scroll pos
m_lastKnownScrollOffset = (int)e.ListScrollTotalDistance;
// Hide the tip box if needed.
HideCommentScrollTipIfNeeded();
// Do the rest of this work on a background thread
Task.Run(() =>
{
// Get the comment manager for this post
lock (m_commentManagers)
{
foreach (FlipViewPostCommentManager manager in m_commentManagers)
{
if (manager.Post.Id.Equals(post.Id))
{
// When found, request more posts
manager.RequestMorePosts();
break;
}
}
}
});
}
/// <summary>
/// Fired when one of the lists are scrolling to the bottom.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void List_OnListEndDetectedEvent(object sender, OnListEndDetected e)
{
// NOTE!!!
// This is a very hot code path, so anything done here should be really quick!
FlipViewPostContext context = GetContext();
if(context == null)
{
return;
}
// Make sure the margin is normal.
if (ui_stickyHeader.Margin.Top != 0)
{
// If the margin is not 0 we are playing our render tick. If the sticky header
// is always set to collapsed it actually never loads or render until we set it to
// visible while we are scrolling which makes it 'pop' in with a delay. To avoid this
// it defaults visible but way off the screen, this makes it load and render so it is ready
// when we set it visible. Here is is safe to restore it to the normal state.
ui_stickyHeader.Visibility = Visibility.Collapsed;
ui_stickyHeader.Margin = new Thickness(0, 0, 0, 0);
}
// Show or hide the scroll bar depending if we have gotten to comments yet or not.
ScrollViewer.SetVerticalScrollBarVisibility(ui_listView, e.ListScrollTotalDistance > 60 ? ScrollBarVisibility.Auto : ScrollBarVisibility.Hidden);
// Find the header size for this post
int currentScrollAera = GetCurrentScrollArea();
// This will return -1 if we can't get this yet, so just get out of here.
if (currentScrollAera == -1)
{
return;
}
// Use the header size and the control size to figure out if we should show the static header.
bool showHeader = e.ListScrollTotalDistance > currentScrollAera - ui_stickyHeader.ActualHeight;
ui_stickyHeader.Visibility = showHeader ? Visibility.Visible : Visibility.Collapsed;
// Get the distance for the animation header to move. We need to account for the header
// size here because when we move from full screen to not it will toggle. This is very touchy, we
// also only want to do this logic if we are scrolling down. On the way back up we need to unminimize
// (if the user forced us to be mini) before we hit the real header or things will be wack.
int headerAniamtionDistance = currentScrollAera;
if(m_isFullscreen && e.ScrollDirection != ScrollDirection.Up)
{
Grid headerGrid = (Grid)m_storyHeader.FindName("ui_storyHeaderBlock");
headerAniamtionDistance -= (int)headerGrid.ActualHeight;
}
// If we are far enough to also hide the header consider hiding it.
if (e.ListScrollTotalDistance > headerAniamtionDistance)
{
if (App.BaconMan.UiSettingsMan.FlipView_MinimizeStoryHeader)
{
if (e.ScrollDirection == ScrollDirection.Down)
{
ToggleFullscreen(true);
}
else if(e.ScrollDirection == ScrollDirection.Up)
{
ToggleFullscreen(false);
}
}
}
else
{
// If we are the top force it.
ToggleFullscreen(false, true);
}
// If we have a differed header update and we are near the top (not showing the header)
// do the update now. For a full story see the comment on m_hasDeferredHeaderSizeUpdate
if (currentScrollAera != context.HeaderSize && context.HeaderSize + 80 > e.ListScrollTotalDistance && e.ScrollDirection == ScrollDirection.Up)
{
SetHeaderSize();
}
//// Update the last known scroll pos
m_lastKnownScrollOffset = (int)e.ListScrollTotalDistance;
//// Hide the tip box if needed.
HideCommentScrollTipIfNeeded();
// If we have a manager request more posts.
if (m_commentManager != null)
{
if (m_commentManager.IsOnlyShowingSubset())
{
m_commentManager.RequestMorePosts();
}
}
}
