private async void PrintDocument_PrintTaskOptionsChanged(CanvasPrintDocument sender, CanvasPrintTaskOptionsChangedEventArgs args)
{
var deferral = args.GetDeferral();
try
{
await EnsureBitmapsLoaded(sender);
var pageDesc = args.PrintTaskOptions.GetPageDescription(1);
var newPageSize = pageDesc.PageSize.ToVector2();
if (pageSize == newPageSize && pageCount != -1)
{
// We've already figured out the pages and the page size hasn't changed, so there's nothing left for us to do here.
return;
}
pageSize = newPageSize;
sender.InvalidatePreview();
// Figure out the bitmap index at the top of the current preview page. We'll request that the preview defaults to showing
// the page that still has this bitmap on it in the new layout.
int indexOnCurrentPage = 0;
if (pageCount != -1)
{
indexOnCurrentPage = (int)(args.CurrentPreviewPageNumber - 1) * bitmapsPerPage;
}
// Calculate the new layout
var printablePageSize = pageSize * 0.9f;
cellSize = largestBitmap + imagePadding;
var cellsPerPage = printablePageSize / cellSize;
columns = Math.Max(1, (int)Math.Floor(cellsPerPage.X));
rows = Math.Max(1, (int)Math.Floor(cellsPerPage.Y));
bitmapsPerPage = columns * rows;
// Calculate the page count
bitmapCount = bitmaps.Count;
pageCount = (int)Math.Ceiling(bitmapCount / (double)bitmapsPerPage);
sender.SetPageCount((uint)pageCount);
// Set the preview page to the one that has the item that was currently displayed in the last preview
args.NewPreviewPageNumber = (uint)(indexOnCurrentPage / bitmapsPerPage) + 1;
}
finally
{
deferral.Complete();
}
}
private void PrintDocument_PrintTaskOptionsChanged(CanvasPrintDocument sender, CanvasPrintTaskOptionsChangedEventArgs args)
{
PrintPageDescription pageDesc = args.PrintTaskOptions.GetPageDescription(1);
Vector2 newPageSize = pageDesc.PageSize.ToVector2();
if (_pageSize == newPageSize)
{
// We've already figured out the pages and the page size hasn't changed,
// so there's nothing left for us to do here.
return;
}
_pageSize = newPageSize;
sender.InvalidatePreview();
sender.SetPageCount(1);
args.NewPreviewPageNumber = 1;
}
private async void PrintDocument_PrintTaskOptionsChanged(CanvasPrintDocument sender, CanvasPrintTaskOptionsChangedEventArgs args)
{
var deferral = args.GetDeferral();
try
{
await EnsureBitmapsLoaded(sender);
var pageDesc = args.PrintTaskOptions.GetPageDescription(1);
var newPageSize = pageDesc.PageSize.ToVector2();
if (pageSize == newPageSize && pageCount != -1)
{
// We've already figured out the pages and the page size hasn't changed, so there's nothing left for us to do here.
return;
}
pageSize = newPageSize;
sender.InvalidatePreview();
// Figure out the bitmap index at the top of the current preview page. We'll request that the preview defaults to showing
// the page that still has this bitmap on it in the new layout.
int indexOnCurrentPage = 0;
if (pageCount != -1)
{
indexOnCurrentPage = (int)(args.CurrentPreviewPageNumber - 1) * bitmapsPerPage;
}
// Calculate the new layout
var printablePageSize = pageSize * 0.9f;
cellSize = largestBitmap + imagePadding;
var cellsPerPage = printablePageSize / cellSize;
columns = Math.Max(1, (int)Math.Floor(cellsPerPage.X));
rows = Math.Max(1, (int)Math.Floor(cellsPerPage.Y));
bitmapsPerPage = columns * rows;
// Calculate the page count
bitmapCount = bitmaps.Count;
pageCount = (int)Math.Ceiling(bitmapCount / (double)bitmapsPerPage);
sender.SetPageCount((uint)pageCount);
// Set the preview page to the one that has the item that was currently displayed in the last preview
args.NewPreviewPageNumber = (uint)(indexOnCurrentPage / bitmapsPerPage) + 1;
}
finally
{
deferral.Complete();
}
}