| content | Text, image and tooltip the button displays. |
| buttonNames | The list of options in the dropdown menu. |
| callback | The callback to fire when a dropdown menu item is selected. |
| disableMainButton | Whether to disable the button. The default value is `false`. |
bool
true when the user clicks the button.
Creates a large button that contains a regular button section and an arrow to open a dropdown menu.
When the user selects the button section the method returns true. When the user selects the dropdown arrow a dropdown menu appears. When the user selects an item in the dropdown menu, callback is fired with the selected menu item as input.