Any guides on how to build custom `Indication` ? :thinking_face: I am having trouble understanding h...

# compose

[theapache64]

Any guides on how to build custom Indication ? 🤔
I am having trouble understanding how do I animate inside IndicationInstance#ContentDrawScope.drawIndication() .Problem is, its not a @Composable method, which means I can’t use animation API methods such as animateXXXasState()

[Adam Powell]

Indication.rememberUpdatedInstance(InteractionSource) is a @Composable function. Any instance-specific composition to observe the InteractionSource and animate the returned IndicationInstance can be done there

[theapache64]

ohh okay. is there any way i can have multiple indicators on top of one element. for eg, can i draw another indicator on top of ripple ?

[Louis Pullen-Freilich [G]]

You could build your own IndicationInstance that draws some indication, and draws the ripple indication as well, although this sounds a bit suspicious and maybe not what you actually would want to do?

On a side note, there is not much guidance currently - but it is something we are working on.

[theapache64]

I don’t understand how we’ll draw two indicators at the same time 🤔 can you explain a little more?

[Louis Pullen-Freilich [G]]

Well, I think you can either just do:

Modifier.indication(/* ripple */).indication(/** custom indication */)

So have two different indications, one for the ripple and one for your custom one.

Or you could create an instance that wraps the ripple instance, and draws both:

class CustomIndicationInstance(private val rippleInstance: IndicationInstance) : IndicationInstance {
    override fun ContentDrawScope.drawIndication() {
        // draw content, and ripple
        with (rippleInstance) { drawIndication() }

        // draw custom indication on top of ripple
        ...
    }
}

Depends what exactly you want to do

[theapache64]

ohhh we can apply indicator through modifier, that’s nice. that’s better than the second approach IMO.

[Louis Pullen-Freilich [G]]

Yeah, it depends what you need to do. If you wanted to clip the ripple / apply a scale effect to the ripple as well for example, then you would need to do the second approach - since it allows you to apply transformations to the ripple effect as well

[theapache64]

It works!! 🚀 Thanks mate