I am using RadPDFViewer, i built a specific toolbar for manage the funcionalities of the viewer.

I didn´t found the any event when the current page is changed in viewer. I would like to show a label "Page NN of TT".

 I found this "https://www.telerik.com/forums/page-changed-detected", but didn´t have this event in RadPDFViewer.

Whats the better solution for the raise event when the current page displayed is changed? 

Can you help me ?!? 

Add bookmarks functionality

Import documents that use this type of encryption. Currently, a handled NotSupportedEncryptionException with message "The encryption method with code 5 is not supported." is thrown while importing such a document.

It will be a great addition of RadPdfViewer if it supports forms/controls.

The events should provide information as to when a page is about to be rendered and when it is displayed in the control.

1. Load file which is signed with digital signature
2. Scroll to the end of document - you will see that the signature is not visible.  

Note: If you use the next button to navigate to the next search result, the user should be notified when the end of the document is reached as well.

Workaround:

public Form1()
{
    InitializeComponent(); 
    this.radPdfViewer1.LoadDocument(@"..\..\..\samplePdf.pdf"); 

    //create a new button
    CommandBarButton findNext = new CommandBarButton();
    findNext.Text = PdfViewerLocalizationProvider.CurrentProvider.GetLocalizedString(PdfViewerStringId.NavigatorFindNextButton);
    findNext.Click += findNext_Click;
    findNext.Image = this.radPdfViewerNavigator1.FindNextButton.Image;
    //hide the currently available button
    this.radPdfViewerNavigator1.DefaultStrip.Items.Add(findNext);
    this.radPdfViewerNavigator1.FindNextButton.Visibility = ElementVisibility.Collapsed;
}

private void findNext_Click(object sender, EventArgs e)
{
    if (this.radPdfViewerNavigator1.SearchTextBox.Text != string.Empty)
    { 
        if (this.radPdfViewerNavigator1.AssociatedViewer == null || this.radPdfViewerNavigator1.AssociatedViewer.Document == null)
        {
            return;
        }

        PropertyInfo internalDocumentPI = typeof(RadFixedDocument).GetProperty("InternalDocument", BindingFlags.NonPublic | BindingFlags.Instance);
        object internalDocument = internalDocumentPI.GetValue(this.radPdfViewerNavigator1.AssociatedViewer.Document, null);
        object textSearch = internalDocument.GetType().GetProperty("TextSearch", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(internalDocument, null);
        MethodInfo mi = textSearch.GetType().GetMethod("Find", BindingFlags.Public | BindingFlags.Instance);
        TextSearchOptions searchOptions = new TextSearchOptions(false);
        SearchResult searchResult = mi.Invoke(textSearch, new object[2] { this.radPdfViewerNavigator1.SearchTextBox.Text, searchOptions }) as SearchResult;
        if (searchResult.Result != null)
        {
            this.radPdfViewerNavigator1.AssociatedViewer.Select(searchResult);
        }
        else
        {
            RadMessageBox.Show("No matches");
        }
    }
}

It will be a nice addition to RadPdfViewer if it can export page thumbnails as an image.

Add an option to save and/or email document. It is especially useful if a file stream is loaded into the viewer.

Currently, the following approach can be used: 
private Stream GetPdfStream()
{

Type documentType = this.radPdfViewer1.PdfViewerElement.Document.GetType();

FieldInfo internalDocumentField = documentType.GetField("internalDocument", BindingFlags.NonPublic | BindingFlags.Instance);

object internalDocumentValue = internalDocumentField.GetValue(this.radPdfViewer1.PdfViewerElement.Document);

FieldInfo formatProviderField = internalDocumentValue.GetType().GetField("formatProvider", BindingFlags.NonPublic | BindingFlags.Instance);

PdfFormatProvider formatProvder = formatProviderField.GetValue(internalDocumentValue) as PdfFormatProvider;

FieldInfo field = formatProvder.GetType().GetField("stream", BindingFlags.NonPublic | BindingFlags.GetField | BindingFlags.Instance);

Stream stream = field.GetValue(formatProvder) as Stream;
return stream;
}

Workaround: until the feature be implemented one can print each page individually respecting its orientation whether it is portrait or landscape
public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
 
        this.radPdfViewer1.LoadDocument(@"..\..\sample.pdf");
    }
 
    private void radButton1_Click(object sender, EventArgs e)
    {
        RadPrintDocument doc = new RadPrintDocument();
        doc.AssociatedObject = this.radPdfViewer1;
 
        for (int i = 0; i < this.radPdfViewer1.Document.Pages.Count; i++)
        {
            RadFixedPage page = this.radPdfViewer1.Document.Pages[i];
 
            doc.CurrentPage = i;
            doc.PrinterSettings.PrintRange = PrintRange.CurrentPage;
            doc.Landscape = page.ActualWidth > page.ActualHeight;
 
            doc.Print();
        }
    }
}

Add two additional buttons in the RadPdfViewerNavigator like in Adobe Reader:
- The first one must fill the window with each page and scroll through pages continuously. 
- The second one must show one page at a time.

http://docs.telerik.com/devtools/wpf/controls/radpdfviewer/document-model/exceptionhandling

ADD. RadPdfViewer - add ability to show the document pages as thumbnails

radPdfViewer1.PdfViewerElement.Find("keyword", PageNumber);

Resolution: 
You can use the following code snippet: 
radPdfViewer1.PdfViewerElement.Find(string text, int pageNumber)