How to save loaded PDF document in application level?
The PDF document in the Xamarin PDF viewer is saved in the application level. PDF viewer returns the PDF document along with the changes made (annotations addition and modification) as stream when tapping the save button in the default toolbar as an event argument of the DocumentSaveInitiated event. This stream is saved as a file locally in Xamarin Forms Android, iOS, and UWP platforms by using DependencyService in Xamarin.Forms. These platform specific saving options are used by defining an interface in the portable project. Refer to the following code snippets.
Portable
Define the following interface.
C#
namespace SavePDFUsingNative
{
public interface ISave
{
string Save(MemoryStream fileStream);
}
}
Load the PDF to PdfViewer and invoke save method with the stream obtained from the DocumentSaveInitiated event using DependencyService. Then, give the name of the interface as type parameter to the method DependencyService.Get<T>().
C#
public MainPage()
{
InitializeComponent();
m_pdfDocumentStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("SavePDFUsingNative.Assets.GIS Succinctly.pdf");
pdfViewerControl.LoadDocument(m_pdfDocumentStream);
pdfViewerControl.DocumentSaveInitiated += PdfViewerControl_DocumentSaveInitiated;
}
private void PdfViewerControl_DocumentSaveInitiated(object sender, Syncfusion.SfPdfViewer.XForms.DocumentSaveInitiatedEventArgs args)
{
string filePath = DependencyService.Get<ISave>().Save(args.SaveStream as MemoryStream);
string message = "The PDF has been saved to " + filePath;
DependencyService.Get<IAlertView>().Show(message);
}
Implement the interface in the platform projects with the available platform specific saving options.
Android
C#
[assembly:Dependency(typeof(SavePDFUsingNative.Droid.SaveAndroid))]
namespace SavePDFUsingNative.Droid
{
public class SaveAndroid : ISave
{
public string Save(MemoryStream stream)
{
string root = null;
string fileName = "SavedDocument.pdf";
if (Android.OS.Environment.IsExternalStorageEmulated)
{
root = Android.OS.Environment.ExternalStorageDirectory.ToString();
}
Java.IO.File myDir = new Java.IO.File(root + "/Syncfusion");
myDir.Mkdir();
Java.IO.File file = new Java.IO.File(myDir, fileName);
string filePath = file.Path;
if (file.Exists()) file.Delete();
Java.IO.FileOutputStream outs = new Java.IO.FileOutputStream(file);
outs.Write(stream.ToArray());
var ab = file.Path;
outs.Flush();
outs.Close();
return filePath;
}
}
}
iOS
C#
[assembly: Dependency(typeof(SavePDFUsingNative.iOS.SaveiOS))]
namespace SavePDFUsingNative.iOS
{
public class SaveiOS : ISave
{
public string Save(MemoryStream fileStream)
{
string path = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
string filepath = Path.Combine(path, "SavedDocument.pdf");
FileStream outputFileStream = File.Open(filepath, FileMode.Create);
fileStream.Position = 0;
fileStream.CopyTo(outputFileStream);
outputFileStream.Close();
return filepath;
}
}
}
UWP
C#
[assembly: Dependency(typeof(SavePDFUsingNative.UWP.SaveWindows))]
namespace SavePDFUsingNative.UWP
{
public class SaveWindows : ISave
{
MemoryStream stream;
StorageFolder folder;
StorageFile file;
public string Save(MemoryStream documentStream)
{
documentStream.Position = 0;
stream = documentStream;
SaveAsync();
return Path.Combine(ApplicationData.Current.LocalFolder.Path, "SavedDocument.pdf");
}
private async void SaveAsync()
{
folder = ApplicationData.Current.LocalFolder;
file = await folder.CreateFileAsync("SavedDocument.pdf", CreationCollisionOption.ReplaceExisting);
if (file != null)
{
Windows.Storage.Streams.IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.ReadWrite);
Stream st = fileStream.AsStreamForWrite();
st.SetLength(0);
st.Write((stream as MemoryStream).ToArray(), 0, (int)stream.Length);
st.Flush();
st.Dispose();
fileStream.Dispose();
}
}
}
}
Sample Link:
https://www.syncfusion.com/downloads/support/directtrac/general/ze/SavePDFUsingNative18258816
