Sets a keydown event handler to the root panel with a non-predefined key. The handler is fired only once when a user presses the bound key command. The same key will be bound to the latest handler set to it.
| Usage | Returns | ui.root.setKeyHandler(keyCode, handler, description) | |
| Argument | Type | Details | keyCode | List | A key code or an array of key codes. For example, ui.Key.A or [ui.Key.SHIFT, ui.Key.A]. |
handler | Function | The handler for the key command. |
description | String, optional | A short description that explains this key command. The description will be visible in the Shortcuts Menu. |