# TGUI001: Describe what your rule checks **Category:** Reliability **Severity:** Warning **Enabled by default:** Yes ## Cause When registering an event handler for `Accepting`, you should set Handled to true, this prevents other subsequent Views from responding to the same input event. ## Reason for rule If you do not do this then you may see unpredictable behaviour such as clicking a Button resulting in another `IsDefault` button in the View also firing. See: - https://github.com/gui-cs/Terminal.Gui/issues/3913 - https://github.com/gui-cs/Terminal.Gui/issues/4170 ## How to fix violations Set Handled to `true` in your event handler ### Examples ```diff var b = new Button(); b.Accepting += (s, e) => { // Do something + e.Handled = true; }; ```