Undo and Redo buttons

[Artur]

Hi,

I have a RadRichTextBoxRibbonUI with an RadRichTextBox. Inside of the RadRichTextBoxRibbonUI i have 6 RadRibbonButtons: copy, paste, cut, undo and redo. What i want to do is to disable this buttons if it isn't possible to do the action.
Example: if i can't do more Undo.


I don't know if it is possible, but i already try everything and i couldn't do.

Thanks

[Boby]

Hello Artur,
Unfortunately these build-in commands does not support this behavior out-of-the-box. I will add this in our to-do list.
You can, however, implement this by yourself, and I will give give you a few hints.

• For updating Undo and Redo buttons, you may attach to DocumentContentChanged event of RadRichTextBox. In the handler, you may update the state of the buttons like this:

  buttonUndo.IsEnabled = radRichTextBox1.Document.History.CanUndo;
  buttonRedo.IsEnabled = radRichTextBox1.Document.History.CanRedo;

• For updating Copy and Paste buttons, you may attach to SelectionChanged event of DocumentSelection class:

  radRichTextBox1.Document.Selection.SelectionChanged += Selection_SelectionChanged;

  In the handler, you may update the state of the buttons like this:

  bool isSelectionEmpty = radRichTextBox1.Document.Selection.IsEmpty;
  buttonCopy.IsEnabled = !isSelectionEmpty;
  buttonCut.IsEnabled = !isSelectionEmpty;

• For the Paste button updating will be tricky, because you have to decide by yourself when to update the state of the button. You can try using the methods of Silverlight's Clipboard class.

All the best,
Boby
the Telerik team