private void OnEnterPanel(AttachToPanelEvent evt)
{
SearchTextField.visualInput.RegisterCallback <FocusEvent>(OnSearchTextFieldFocus);
SearchTextField.visualInput.RegisterCallback <FocusOutEvent>(OnSearchTextFieldFocusOut);
SearchTextField.RegisterCallback <ChangeEvent <string> >(OnSearchTextFieldChange);
SearchTextField.visualInput.RegisterCallback <KeyDownEvent>(OnKeyDownShortcut);
}