Share and Save pdf documents from the PdfViewer Toolbar

Environment

Product Version	2022.1 222.1
Product	PdfViewer for Xamarin

Description

This artilce will show you how to save and share pdf documents loaded in the Telerik PdfViewer for Xamarin.

Solution

For Sharing files we will use the Xamarin.Essentials API

1. The Share and Save options will be added to the Telerik PdfViewer Toolbar. We will add two new PdfViewerToolbarItemBase. Here is the XAMl definition:

   <Grid>
     <Grid.RowDefinitions>
         <RowDefinition Height="Auto"/>
         <RowDefinition />
     </Grid.RowDefinitions>
     <telerikPdfViewer:RadPdfViewerToolbar PdfViewer="{Binding Source={x:Reference pdfViewer}}"
                                       IsScrollable="True">
         <telerikPdfViewer:NavigateToPreviousPageToolbarItem/>
         <telerikPdfViewer:NavigateToNextPageToolbarItem/>
         <telerikPdfViewer:PdfViewerToolbarItemBase Text="Share" 
                                                    Command="{Binding ShareDocumentCommand}" />
         <telerikPdfViewer:PdfViewerToolbarItemBase Text="Save" 
                                                    Command="{Binding SaveDocumentCommand}" />
     </telerikPdfViewer:RadPdfViewerToolbar>
     <telerikPdfViewer:RadPdfViewer x:Name="pdfViewer" Grid.Row="1"
                                    Document="{Binding Document, Mode=OneWayToSource}" />
   </Grid>
   

2. And the namespace used:

   xmlns:telerikPdfViewer="clr-namespace:Telerik.XamarinForms.PdfViewer;assembly=Telerik.XamarinForms.PdfViewer"
   

3. Then we will load a document in the PdfViewer as embedded resource:

   Func<CancellationToken, Task<Stream>> streamFunc = ct => Task.Run(() =>
   {
   Assembly assembly = typeof(MainPage).Assembly;
   string fileName = assembly.GetManifestResourceNames().FirstOrDefault(n => n.Contains("pdfviewer-overview.pdf"));
   Stream stream = assembly.GetManifestResourceStream(fileName);
   return stream;
   });
   this.pdfViewer.Source = streamFunc;
   

   

Save and Share pdf documents.

We will need a ViewModel for the bindings we have. PdfViewer.Document property which we will use for saving the pdf document, and for the two commands we have.

ViewModel with ShareDocumentCommand and SaveDocumentCommand implementation:

public class ViewModel
{
    public ViewModel()
    {
        this.ShareDocumentCommand = new Command(this.ShareDocument);
        this.SaveDocumentCommand = new Command(this.SaveDocument);
    }

    private async void ShareDocument(object obj)
    {
        await ShareAsync();
    }

    // save pdf document
    private void SaveDocument(object obj)
    {

        var fileName = "document.pdf";
        var localFolder = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
        var filePath = Path.Combine(localFolder, fileName);

        using (Stream output = File.OpenWrite(filePath))
        {
            new Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider().Export(this.Document, output);

            Application.Current.MainPage.DisplayAlert("Document is saved to local application data: ", filePath, "OK");
        }
    }

    // share pdf document
    private async Task ShareAsync()
    {
        Assembly assembly = typeof(MainPage).Assembly;
        string fileName = assembly.GetManifestResourceNames().FirstOrDefault(n => n.Contains("pdfviewer-overview.pdf"));
        Stream stream = assembly.GetManifestResourceStream(fileName);
        var cacheFile = Path.Combine(FileSystem.CacheDirectory, "pdfviewer-overview.pdf");
        using (var file = new FileStream(cacheFile, FileMode.Create, FileAccess.Write))
        {
            stream.CopyTo(file);
        }
        var request = new ShareFileRequest {
            Title = "Share pdf document",
            File = new ShareFile(cacheFile)
        };
        await Share.RequestAsync(request);
    }

    public RadFixedDocument Document { get; set; }

    public ICommand SaveDocumentCommand { get; set; }

    public ICommand ShareDocumentCommand { get; set; }
}

Share Doument Result:

Save Document Result: