This is a migrated thread and some comments may be shown as answers.

Restore caret position, selection, and vertical scroll position

1 Answer 281 Views

RichTextEditor

This is a migrated thread and some comments may be shown as answers.

Mihajlo asked on 05 Sep 2018, 04:21 PM

Suppose I add from code some text to a shown document, like this:

try

{

radRichTextEditor1.Document.History.IsEnabled = false;

var editor = new RadDocumentEditor(radRichTextEditor1.Document);

editor.Document.CaretPosition.MoveToLastPositionInDocument();

editor.InsertParagraph();

editor.Insert("XYZ");

editor.Document.CaretPosition.MoveToFirstPositionInDocument();

editor.Insert("ABC");

editor.InsertParagraph();

}

finally

{

radRichTextEditor1.Document.History.IsEnabled = true;

}

This code will destroy document's CaretPosition, Selection, and also user's view to the document (vertical scroll bar location). Is there a way to restore them to previous values?

1 Answer, 1 is accepted

Accepted

answered on 10 Sep 2018, 01:48 PM

Hello Mihajlo,

You can try to use what we call "tracking" document position, for example:

double originalOffset = radRichTextEditor1.VerticalOffset;

double originalY = this.radRichTextBox.Document.CaretPosition.Location.Y;

using (DocumentPosition originalCaretPosition = new DocumentPosition(this.radRichTextBox.Document.CaretPosition, true))

{

try

{

radRichTextEditor1.Document.History.IsEnabled = false;

var editor = new RadDocumentEditor(radRichTextEditor1.Document);

editor.Document.CaretPosition.MoveToLastPositionInDocument();

editor.InsertParagraph();

editor.Insert("XYZ");

editor.Document.CaretPosition.MoveToFirstPositionInDocument();

editor.Insert("ABC");

editor.InsertParagraph();

}

finally

{

radRichTextEditor1.Document.History.IsEnabled = true;

}

radRichTextEditor1.Document.CaretPosition.MoveToPosition(originalCaretPosition);

radRichTextEditor1.ActiveEditorPresenter.ScrollToVerticalOffset(originalOffset - originalY + this.radRichTextBox.Document.CaretPosition.Location.Y);

this.radRichTextBox.UpdateEditorLayout();

radRichTextEditor1.Focus();

}

You can use the same method to preserve the regions of the DocumentSelection (RadRichTextEditor.Document.Selection).

Regards,
Boby
Progress Telerik

Get quickly onboarded and successful with your Telerik and/or Kendo UI products with the Virtual Classroom free technical training, available to all active customers. Learn More.