A Simple Coordinator Layout Behavior To Handle Shrinking And Extending ExtendedFloatingActionButton

ShrinkExtendedFloatingActionButtonOnScrollBehavior.kt

package com.mosius

import android.content.Context
import android.util.AttributeSet
import android.view.View
import androidx.coordinatorlayout.widget.CoordinatorLayout
import androidx.core.view.ViewCompat
import com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton

class ShrinkExtendedFloatingActionButtonOnScrollBehavior : CoordinatorLayout.Behavior<ExtendedFloatingActionButton> {
    constructor() : super()
    constructor(context: Context?, attrs: AttributeSet?) : super(context, attrs)

    override fun onStartNestedScroll(
        coordinatorLayout: CoordinatorLayout,
        child: ExtendedFloatingActionButton,
        directTargetChild: View,
        target: View,
        axes: Int,
        type: Int
    ) = axes == ViewCompat.SCROLL_AXIS_VERTICAL

    override fun onNestedScroll(
        coordinatorLayout: CoordinatorLayout,
        child: ExtendedFloatingActionButton,
        target: View,
        dxConsumed: Int,
        dyConsumed: Int,
        dxUnconsumed: Int,
        dyUnconsumed: Int,
        type: Int,
        consumed: IntArray
    ) {
        if (dyConsumed > 0) {
            child.shrink()
        } else if (dyConsumed < 0) {
            child.extend()
        }
    }
}