problem printing a Legend control

TerryGiles

I have a button in my application which allows the user to print the map using the standard Silverlight PrintDocument class (acutally it 'clones' the map onto another user control which looks like our standard map tempalte).  I'm trying to add a 2nd page to the print doc which contains a legend control.  I'm able to get the 2nd page to print but the legend control aways has the busy indicator next to the layer names (see attached image).  Is there a way to track when the legend has completed building it's tree and contains the layer/sublayer names & symbology? 

The only other way I can think to do it is to use WebClient.DownloadStringAsynch() against each layer's legend (http://server/arcgis/rest/services/Service/Legend?f=pjson) and pull out the layer names and image bytes and put them into my own TreeView...  Anyone have any other ideas?

Thanks,

Terry

legend_print.png

Sample.png

Matthew_Muehlhauser_1-1724679635303.png

TerryGiles

Hello Dominique,

Adding the legend to a user control & thus the visual tree did the trick. 

A huge THANK YOU to both you and Jennifer. 

So far in testing the legend is always ready by the time I get to printing the 2nd page.  Modified code below in case it helps anyone else.  I made 3 other short changes - added a busy indicator, added a checkbox so the user could skip printing the legend (smaller export size), and set the Legend's background to white instead of the default gradient also for smaller export size & cleaner printing.


Thanks again,
Terry

        private void btnOK_Click(Object sender, RoutedEventArgs e)
        {
            busy.IsBusy = true;

            _LayerComplete = 0;
            _LayerCount = 0;

            //get map and legend prep'd
            _pp = _Parent.Printpage;
            _pp.setMap(_Map);
            _pp.Visibility = Visibility.Visible;
            (_pp.LayoutRoot.FindName("txtTitle") as TextBlock).Text = txtTitle.Text;
            (_pp.LayoutRoot.FindName("txtDate") as TextBlock).Text = "Created: " + DateTime.Now.ToShortDateString();

            _lgnd = new Legend();
            _ppl = _Parent.PrintLegend;
            _ppl.LayoutRoot.Children.Add(_lgnd);
            _lgnd.ShowOnlyVisibleLayers = true;
            _lgnd.LayerItemsMode = Legend.Mode.Tree;
            _lgnd.Map = _pp.mapPrint;
            _lgnd.Refreshed += _lgnd_Refreshed;
            _lgnd.Background = new SolidColorBrush(Colors.White);  //overwrite default gradient - smaller output size

            //drop tiled services since they dont have a legend with symbology
            List<string> layIDs = new List<string>();
            foreach (Layer lyr in _pp.mapPrint.Layers.Where(t => !(t is ArcGISTiledMapServiceLayer)))
            {
                layIDs.Add(lyr.ID);
                _LayerCount++;
            }
            layIDs.Reverse();
            _lgnd.LayerIDs = layIDs.ToArray();

             _doc = new PrintDocument();
            _doc.PrintPage +=  doc_PrintPage1;
            _doc.EndPrint += doc_EndPrint;
            _doc.Print("AweMap_" + txtTitle.Text);

        }

        void _lgnd_Refreshed(object sender, Legend.RefreshedEventArgs e)
        {
            //see if LIVM that fired refreshed is no longer busy; increment layer complete counter
            e.LayerItem.PropertyChanged += (s,evnt) =>
            {
                if ( (!(s as LayerItemViewModel).IsBusy) && evnt.PropertyName.ToLower() == "isbusy")
                {
                    _LayerComplete++;
                }
            };

        }

        void doc_PrintPage1(object sender, PrintPageEventArgs args)
        {
            _pp.Width = args.PrintableArea.Height;
            _pp.Height = args.PrintableArea.Width;
            _pp.UpdateLayout();

            if (rbLand.IsChecked.GetValueOrDefault(true))
            {
                //rotate to landscape
                TransformGroup transformGroup = new TransformGroup();
                transformGroup.Children.Add(new RotateTransform() { Angle = 90 });
                transformGroup.Children.Add(new TranslateTransform() { X = args.PrintableArea.Width });
                _pp.RenderTransform = transformGroup;
            }

            args.PageVisual = _pp;

            //see if user selected to include legend:D
            if (chkLegend.IsChecked.GetValueOrDefault(true))
            {
                //swap handler for 2nd page w/ legend control
                _doc.PrintPage -= doc_PrintPage1;
                _doc.PrintPage += doc_PrintPage2;
                args.HasMorePages = true;
            }
            else
            {
                args.HasMorePages = false;
            }
        }

        void doc_PrintPage2(object sender, PrintPageEventArgs args)
        {
            _pp.Width = args.PrintableArea.Height;
            _pp.Height = args.PrintableArea.Width;
            _lgnd.Width = _ppl.Width - 50;
            _lgnd.Height = _ppl.Height - 50;

            if (_LayerComplete < _LayerCount)
            {
                System.Diagnostics.Debug.WriteLine("Waiting for Legend...");
                System.Threading.Thread.Sleep(1000);
                args.PageVisual = null;
                args.HasMorePages = true;
            }
            else
            {
                args.PageVisual = _lgnd;
                args.HasMorePages = false;
            }

        }