title: TTreeView: How to change the text of item's inplace editor?
body: <p>I have a TreeView with editable items. When I press F2 or click any item after selection, the inplace editor appearing.</p>
  
  <p>How can I change the text which is displayed in that editor before showing it? For example, my tree item's text is <code>Point 1 (300, 450)</code>, but I want my inplace editor to display only <code>Point 1</code>.</p>
  
  <p>I tried to catch <code>OnEditing</code> event like that:</p>
  
  <pre><code>procedure TForm1.TreeViewEditing(Sender: TObject; Node: TTreeNode; 
    var AllowEdit: Boolean);
  begin
    AllowEdit := True;
    Node.Text := 'text to edit';
  end;
  </code></pre>
  
  <p>However, the text of inplace editor isn't changing, the tree item's text updated only after cancelling edit. How to do this correctly?</p>