There's no way to make the effect visible/invisible depending on certain conditions or user actions

Preconditions

1. Create a New Effect
2. Save it in order to generate the QML code
3. Assign the Effect to an item in Screen01.ui.qml

Description

The generated QML file doesn't expose any property / function that would allow a user to enable/disable the effect depending on application's state, conditions or user action.

For example, I'd like to enable a snow effect on the background of the main window when a checkbox is checked.

The only way to do that is to directly access the parent of the effect and modify its layer.enabled property. Since the parent properties are set internally by the Effect implementation, it'd be cumbersome if a user needs to access them directly. There's no way to enable/disable the effect by the properties exposed by the effect itself.