/// <summary>
/// A KeyHandler method used by SearchView, increments decrements and executes based on input.
/// </summary>
/// <param name="sender">Originating object for the KeyHandler </param>
/// <param name="e">Parameters describing the key push</param>
public void KeyHandler(object sender, KeyEventArgs e)
{
// ignore the key command if modifiers are present
if (e.KeyboardDevice.IsKeyDown(Key.LeftCtrl) ||
e.KeyboardDevice.IsKeyDown(Key.RightCtrl) ||
e.KeyboardDevice.IsKeyDown(Key.LeftAlt) ||
e.KeyboardDevice.IsKeyDown(Key.RightAlt))
{
return;
}
switch (e.Key)
{
case Key.Return:
viewModel.Execute();
break;
case Key.Delete:
if (DynamoSelection.Instance.Selection.Count > 0)
{
e.Handled = true;
this.dynamoViewModel.DeleteCommand.Execute(null);
}
//if there are no nodes being selected, the delete key should
//delete the text in the search box of library preview
else
{
//if there is no text, then jump out of the switch
if (String.IsNullOrEmpty(SearchTextBox.Text))
{
break;
}
else
{
int cursorPosition = SearchTextBox.SelectionStart;
string searchBoxText = SearchTextBox.Text;
//if some piece of text is seleceted by users.
//delete this piece of text
if (SearchTextBox.SelectedText != "")
{
searchBoxText = searchBoxText.Remove(cursorPosition,
SearchTextBox.SelectionLength);
}
//if there is no text selected, delete the character after the cursor
else
{
//the cursor is at the end of this text string
if (cursorPosition == searchBoxText.Length)
{
break;
}
else
{
searchBoxText = searchBoxText.Remove(cursorPosition, 1);
}
}
//update the SearchTextBox's text and the cursor position
SearchTextBox.Text = searchBoxText;
SearchTextBox.SelectionStart = cursorPosition;
}
}
break;
case Key.Tab:
viewModel.PopulateSearchTextWithSelectedResult();
break;
case Key.Down:
viewModel.SelectNext();
break;
case Key.Up:
viewModel.SelectPrevious();
break;
}
}