Need to print UWP MapControl with route results - printing

Question

I have a MapControl working just creating my route. Now, I just need to figure out a way to print it out. Using the UWP printing sample, I get a black box where the control should be. The map and route are being built, just not rendered correctly in the print preview. I thought I saw a MapControl.Print... but I think that was in the Bing.Maps stuff. Any pointers would be appreciated. Thanks.

Answer 1

Using the UWP printing sample, I get a black box where the control should be.
It seems the MapControl can not be printed.
As a workround, we can use RenderTargetBitmap to get the image from the MapControl. That we can print the image.
Using a RenderTargetBitmap, you can accomplish scenarios such as applying image effects to a visual that originally came from a XAML UI composition, generating thumbnail images of child pages for a navigation system, or enabling the user to save parts of the UI as an image source and then share that image with other apps.
Because RenderTargetBitmap is a subclass of ImageSource, it can be used as the image source for Image elements or an ImageBrush brush.
For more info,see RenderTargetBitmap.
For example:
RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap();
await renderTargetBitmap.RenderAsync(MyMap);
MyImage.Source = renderTargetBitmap;
The printing code:
public sealed partial class MainPage : Page
{
private PrintManager printmgr = PrintManager.GetForCurrentView();
private PrintDocument printDoc = null;
private PrintTask task = null;
public MainPage()
{
this.InitializeComponent();
printmgr.PrintTaskRequested += Printmgr_PrintTaskRequested;
}
private void Printmgr_PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs args)
{
var deferral = args.Request.GetDeferral();
task = args.Request.CreatePrintTask("Print", OnPrintTaskSourceRequrested);
task.Completed += PrintTask_Completed;
deferral.Complete();
}
private void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
//the PrintTask is completed
}
private async void OnPrintTaskSourceRequrested(PrintTaskSourceRequestedArgs args)
{
var def = args.GetDeferral();
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
() =>
{
args.SetSource(printDoc?.DocumentSource);
});
def.Complete();
}
private async void appbar_Printer_Click(object sender, RoutedEventArgs e)
{
if (printDoc != null)
{
printDoc.GetPreviewPage -= OnGetPreviewPage;
printDoc.Paginate -= PrintDic_Paginate;
printDoc.AddPages -= PrintDic_AddPages;
}
this.printDoc = new PrintDocument();
printDoc.GetPreviewPage += OnGetPreviewPage;
printDoc.Paginate += PrintDic_Paginate;
printDoc.AddPages += PrintDic_AddPages;
bool showPrint = await PrintManager.ShowPrintUIAsync();
}
private void PrintDic_AddPages(object sender, AddPagesEventArgs e)
{
printDoc.AddPage(this);
printDoc.AddPagesComplete();
}
private void PrintDic_Paginate(object sender, PaginateEventArgs e)
{
PrintTaskOptions opt = task.Options;
printDoc.SetPreviewPageCount(1, PreviewPageCountType.Final);
}
private void OnGetPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDoc.SetPreviewPage(e.PageNumber, this);
}
}