System.InvalidOperationException: 'Must not change font resolver after is was once used.'

[divyesh008]

The print pdf button works fine for the first time but when again I am clicking Print pdf button the app is crashing. I have test this in UWP simulator.

Exception Details

System.InvalidOperationException
  HResult=0x80131509
  Message=Must not change font resolver after is was once used.
  Source=PdfSharpCore
  StackTrace:
   at PdfSharpCore.Fonts.GlobalFontSettings.set_FontResolver(IFontResolver value)
   at PDFDemo.PDFReports.ProductsReport..ctor(List`1 items) in D:\Demos\PDFDemo-master\PDFDemo-master\PDFDemo\PDFDemo\PDFReports\ProductsReport.cs:line 30
   at PDFDemo.ViewModels.ProductListViewModel.<PrintPdf>d__17.MoveNext() in D:\Demos\PDFDemo-master\PDFDemo-master\PDFDemo\PDFDemo\ViewModels\ProductListViewModel.cs:line 46
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at PDFDemo.ViewModels.ProductListViewModel.<<-ctor>b__19_1>d.MoveNext() in D:\Demos\PDFDemo-master\PDFDemo-master\PDFDemo\PDFDemo\ViewModels\ProductListViewModel.cs:line 64

  This exception was originally thrown at this call stack:
    [External Code]
    PDFDemo.PDFReports.ProductsReport.ProductsReport(System.Collections.Generic.List<PDFDemo.Models.Product>) in ProductsReport.cs
    PDFDemo.ViewModels.ProductListViewModel.PrintPdf() in ProductListViewModel.cs
    [External Code]
    PDFDemo.ViewModels.ProductListViewModel..ctor.AnonymousMethod__19_1() in ProductListViewModel.cs

[JorgeTorresPadron]

I resolve this using a try-catch.

In this proyect he generates the pdfs using a command in "ProductListViewModel". The first time the user generates the pdf the fonts are loaded. The following times the user generates a pdf the fonts aren´t loaded so it doesn´t fail

private async Task PrintPdf()
{
   //this is the try-catch you have to add in ProductListViewModel
   try
   {
       GlobalFontSettings.FontResolver = new GenericFontResolver();

        var pdfReport = new PDFReports.ProductsReport(products);
        await pdfReport.CreateReport();
   }
   catch
   {
        var pdfReport = new PDFReports.ProductsReport(products);
        await pdfReport.CreateReport();
   }
}