/// <summary>
/// Generates a page containing a photo.
/// The image will be rotated if detected that there is a gain from that regarding size (try to maximize photo size).
/// </summary>
/// <param name="photoNumber">The photo number.</param>
/// <param name="pageDescription">The description of the printer page.</param>
/// <returns>A task that will return the page.</returns>
private async Task <UIElement> GeneratePageAsync(int photoNumber, PageDescription pageDescription, WriteableBitmap bitmap)
{
Canvas page = new Canvas
{
Width = pageDescription.PageSize.Width,
Height = pageDescription.PageSize.Height
};
Canvas viewablePage = new Canvas()
{
Width = pageDescription.ViewablePageSize.Width,
Height = pageDescription.ViewablePageSize.Height
};
viewablePage.SetValue(Canvas.LeftProperty, pageDescription.Margin.Width);
viewablePage.SetValue(Canvas.TopProperty, pageDescription.Margin.Height);
// The image "frame" which also acts as a viewport
Grid photoView = new Grid
{
Width = pageDescription.PictureViewSize.Width,
Height = pageDescription.PictureViewSize.Height
};
// Center the frame.
photoView.SetValue(Canvas.LeftProperty, (viewablePage.Width - photoView.Width) / 2);
photoView.SetValue(Canvas.TopProperty, (viewablePage.Height - photoView.Height) / 2);
if (bitmap != null)
{
Image image = new Image
{
Source = bitmap,
HorizontalAlignment = Windows.UI.Xaml.HorizontalAlignment.Center,
VerticalAlignment = Windows.UI.Xaml.VerticalAlignment.Center
};
// Use the real image size when croping or if the image is smaller then the target area (prevent a scale-up).
if (photoScale == Scaling.Crop ||
(bitmap.PixelWidth <= pageDescription.PictureViewSize.Width &&
bitmap.PixelHeight <= pageDescription.PictureViewSize.Height))
{
image.Stretch = Stretch.None;
image.Width = bitmap.PixelWidth;
image.Height = bitmap.PixelHeight;
}
// Add the newly created image to the visual root.
photoView.Children.Add(image);
viewablePage.Children.Add(photoView);
page.Children.Add(viewablePage);
}
// Return the page with the image centered.
return(page);
}
/// <summary>
/// This is the event handler for PrintManager.PrintTaskRequested.
/// In order to ensure a good user experience, the system requires that the app handle the PrintTaskRequested event within the time specified
/// by PrintTaskRequestedEventArgs->Request->Deadline.
/// Therefore, we use this handler to only create the print task.
/// The print settings customization can be done when the print document source is requested.
/// </summary>
/// <param name="sender">The print manager for which a print task request was made.</param>
/// <param name="e">The print taks request associated arguments.</param>
protected override void PrintTaskRequested(Windows.Graphics.Printing.PrintManager sender, Windows.Graphics.Printing.PrintTaskRequestedEventArgs e)
{
PrintTask printTask = null;
printTask = e.Request.CreatePrintTask("Print Your QR Code", sourceRequestedArgs =>
{
PrintTaskOptionDetails printDetailedOptions = PrintTaskOptionDetails.GetFromPrintTaskOptions(printTask.Options);
// Choose the printer options to be shown.
// The order in which the options are appended determines the order in which they appear in the UI
printDetailedOptions.DisplayedOptions.Clear();
printDetailedOptions.DisplayedOptions.Add(Windows.Graphics.Printing.StandardPrintTaskOptions.MediaSize);
printDetailedOptions.DisplayedOptions.Add(Windows.Graphics.Printing.StandardPrintTaskOptions.Copies);
// Create a new list option.
PrintCustomItemListOptionDetails photoSize = printDetailedOptions.CreateItemListOption("photoSize", "Photo Size");
photoSize.AddItem("SizeFullPage", "Full Page");
photoSize.AddItem("Size4x6", "4 x 6 in");
photoSize.AddItem("Size5x7", "5 x 7 in");
photoSize.AddItem("Size8x10", "8 x 10 in");
// Add the custom option to the option list.
printDetailedOptions.DisplayedOptions.Add("photoSize");
PrintCustomItemListOptionDetails scaling = printDetailedOptions.CreateItemListOption("scaling", "Scaling");
scaling.AddItem("ShrinkToFit", "Shrink To Fit");
scaling.AddItem("Crop", "Crop");
// Add the custom option to the option list.
printDetailedOptions.DisplayedOptions.Add("scaling");
// Set default orientation to landscape.
printTask.Options.Orientation = PrintOrientation.Landscape;
// Register for print task option changed notifications.
printDetailedOptions.OptionChanged += PrintDetailedOptionsOptionChanged;
// Register for print task Completed notification.
// Print Task event handler is invoked when the print job is completed.
printTask.Completed += async(s, args) =>
{
await scenarioPage.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
ClearPageCollection();
// Reset image options to default values.
this.photoScale = Scaling.ShrinkToFit;
this.photoSize = PhotoSize.SizeFullPage;
// Reset the current page description
currentPageDescription = null;
// Notify the user when the print operation fails.
if (args.Completion == PrintTaskCompletion.Failed)
{
}
});
};
// Set the document source.
sourceRequestedArgs.SetSource(printDocumentSource);
});
}
/// <summary>
/// This is the event handler for Pagination.
/// </summary>
/// <param name="sender">The document for which pagination occurs.</param>
/// <param name="e">The pagination event arguments containing the print options.</param>
protected override void CreatePrintPreviewPages(object sender, Windows.UI.Xaml.Printing.PaginateEventArgs e)
{
PrintDocument printDoc = (PrintDocument)sender;
// A new "session" starts with each paginate event.
Interlocked.Increment(ref requestCount);
PageDescription pageDescription = new PageDescription();
// Get printer's page description.
PrintTaskOptionDetails printDetailedOptions = PrintTaskOptionDetails.GetFromPrintTaskOptions(e.PrintTaskOptions);
PrintPageDescription printPageDescription = e.PrintTaskOptions.GetPageDescription(0);
// Reset the error state
printDetailedOptions.Options["photoSize"].ErrorText = string.Empty;
// Compute the printing page description (page size & center printable area)
pageDescription.PageSize = printPageDescription.PageSize;
pageDescription.Margin.Width = Math.Max(
printPageDescription.ImageableRect.Left,
printPageDescription.ImageableRect.Right - printPageDescription.PageSize.Width);
pageDescription.Margin.Height = Math.Max(
printPageDescription.ImageableRect.Top,
printPageDescription.ImageableRect.Bottom - printPageDescription.PageSize.Height);
pageDescription.ViewablePageSize.Width = printPageDescription.PageSize.Width - pageDescription.Margin.Width * 2;
pageDescription.ViewablePageSize.Height = printPageDescription.PageSize.Height - pageDescription.Margin.Height * 2;
// Compute print photo area.
switch (photoSize)
{
case PhotoSize.Size4x6:
pageDescription.PictureViewSize.Width = 4 * DPI96;
pageDescription.PictureViewSize.Height = 6 * DPI96;
break;
case PhotoSize.Size5x7:
pageDescription.PictureViewSize.Width = 5 * DPI96;
pageDescription.PictureViewSize.Height = 7 * DPI96;
break;
case PhotoSize.Size8x10:
pageDescription.PictureViewSize.Width = 8 * DPI96;
pageDescription.PictureViewSize.Height = 10 * DPI96;
break;
case PhotoSize.SizeFullPage:
pageDescription.PictureViewSize.Width = pageDescription.ViewablePageSize.Width;
pageDescription.PictureViewSize.Height = pageDescription.ViewablePageSize.Height;
break;
}
// Try to maximize photo-size based on it's aspect-ratio
if ((pageDescription.ViewablePageSize.Width > pageDescription.ViewablePageSize.Height) && (photoSize != PhotoSize.SizeFullPage))
{
var swap = pageDescription.PictureViewSize.Width;
pageDescription.PictureViewSize.Width = pageDescription.PictureViewSize.Height;
pageDescription.PictureViewSize.Height = swap;
}
pageDescription.IsContentCropped = photoScale == Scaling.Crop;
// Recreate content only when :
// - there is no current page description
// - the current page description doesn't match the new one
if (currentPageDescription == null || !currentPageDescription.Equals(pageDescription))
{
ClearPageCollection();
if (pageDescription.PictureViewSize.Width > pageDescription.ViewablePageSize.Width ||
pageDescription.PictureViewSize.Height > pageDescription.ViewablePageSize.Height)
{
printDetailedOptions.Options["photoSize"].ErrorText = "Photo doesn’t fit on the selected paper";
// Inform preview that it has only 1 page to show.
printDoc.SetPreviewPageCount(1, PreviewPageCountType.Intermediate);
// Add a custom "preview" unavailable page
lock (printSync)
{
pageCollection[0] = new PreviewUnavailable(pageDescription.PageSize, pageDescription.ViewablePageSize);
}
}
else
{
// Inform preview that is has #NumberOfPhotos pages to show.
printDoc.SetPreviewPageCount(NumberOfPhotos, PreviewPageCountType.Intermediate);
}
currentPageDescription = pageDescription;
}
}