Best way to have onCreate/onDestroy on a Node

[dimsuz]

What is the best way to have an onCreate/onDestroy handling inside a particular Node?

For example I have a ParentNode and I want to create a CoroutineScope which is created when it is inserted in the graph and is cancel()-ed when Node is removed from the graph.

And also this would have to be repeated in case I navigate to this node again later: new scope would have to be created and then destroyed on exit.

I want to be able to do this from within the node itself, not from its parent.

[KovalevAndrey]

@dimsuz you can use lifecycleScope in the Node. It's created when the Node is created and the scope is cancelled automatically onDestroy

[dimsuz]

I see!

But is there a generic mechanism for this? CoroutineScope was only one example I thought of. I also can have some different resource which I would like to clean up...

[KovalevAndrey]

@dimsuz if you need to clean up your resources, take look at Destroyable plugin. Let your classes implement this plugin and perform cleanup on destroy() method. Destroyable interface must be passed to the list of Node plugins in the constructor

[dimsuz]

Nice, this should work, thank you!

I guess node constructor will act as onCreate, and destroyable plugin will act as onDestroy.

Or perhaps I can have both of these "points" stuffed into a single Plugin implementation, I'll check. Will be nicer to have them in one place for clarity.

[KovalevAndrey]

@dimsuz It depends on your needs. Node is moved in onCreate state when onBuilt() is called. Sometimes doing thing in constructor is too early, and you can use NodeLifecycleAware plugin instead. fun onCreate(lifecycle: Lifecycle) is called when Node onCreate gets created. You can observe lifecycle events do cleanup onDestroy and more