Develop Reference

How to set position floatingactionbutton abave bottom bar

I have activity with FloatingActionButton and BottomNavigationView.
I want FloatingActionButton have position above BottomNavigationView. but no matter what I do, it is always with BottomNavigationView like on img
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity2">
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
app:defaultNavHost="true"
app:navGraph="#navigation/mobile_navigation" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:layout_margin="16dp"
android:src="#drawable/ic_baseline_addchart_24" />
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/yu"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_bar"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:menu="#menu/bottom_menu" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Place FAB button inside the constraint layout and then set the property
app:layout_constraintTop_toBottomOf="#id/fab"
to your Navigation View and
app:layout_constraintBottom_toTopOf="#id/bottom_bar"
android:layout_margin="16dp"
In this way the FAB button will always stay on top of navigation view.

here you go just replace it with your floatbutton tag
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:layout_marginBottom="70dp"
android:layout_marginEnd="16dp"
android:src="#drawable/ic_baseline_addchart_24" />
the bottom navigation is almost 56dp height so what we did is we added 70dp to marginBottom to lift it above the navigation and it will stay there always, you can change that value as your likings :)

Floating Action button is not showing in Android Coordinator Layout

I am new to Android and UI development. I have downloaded latest version of Windows Android studio and did some basic native UI, it worked well. Now, I am trying to develop floating action button UI.
I have added CoordinatorLayout inside ConstraintLayout. FAB is added inside CoordinatorLayout. My FAB is not visible in layout preview.
I see androidx.coordinatorlayout.widget.CoordinatorLayout text in that layout with background color. Please let me know how to fix this
implementation 'com.google.android.material:material:1.2.0'
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#F44336"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
tools:ignore="MissingConstraints">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:backgroundTint="#color/colorPrimary"
android:src="#drawable/ic_baseline_add_24"
android:layout_gravity="bottom|end"
/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

add constraintTop for your CoordinatorLayout for filling whole screen
app:layout_constraintTop_toTopOf="parent"
or even this will be better
android:layout_width="match_parent"
android:layout_height="match_parent"
with removing all constraints
for test you may also add fixed size FloatingActionButton. if you want to keep wrap_content for FAB then ensure that ic_baseline_add_24 is valid icon with proper size
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#F44336"
tools:ignore="MissingConstraints">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:layout_width="80dp"
android:layout_height="80dp"
android:backgroundTint="#color/colorPrimary"
android:src="#drawable/ic_baseline_add_24"
android:layout_gravity="bottom|end"
/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
in above code ConstraintLayout isn't needed and you may remove it if you aren't planning to make some more complicated layout. RecyclerView may be placed inside CoordinatorLayout just before FAB - at first REcyclerView will be drawn, after that FAB on top of recycler

Try
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#F44336"
android:layout_gravity="bottom"
tools:ignore="MissingConstraints">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:layout_width="104dp"
android:layout_height="107dp"
android:layout_gravity="center"
android:foregroundGravity="center"
android:visibility="visible"
android:src="#drawable/ic_baseline_add_24"
app:backgroundTint="#color/colorPrimary" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</LinearLayout>

Don't use a CoordinatorLayout with android:layout_height="wrap_content" to contain just the FAB:
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rvItems"
android:scrollbars="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"
android:layout_margin="#dimen/fab_margin"
app:srcCompat="#drawable/ic_add_24px" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Android : Bottom Menu Bar Hides the Recycler View

in my app i created a bootom menubar layout with floating button and i include that in my main activity and also i place a recycler view in my main activity
i just add 100 items to display in my recyclerview to check whether it was working or not for that when i run my application the recycler view of last item hides inside the bottom menu bar how to solve this
here is the sample image of what i said
activity_main.xml
<include
layout="#layout/toolbar"
android:id="#+id/toolbar"
/>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycle"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#id/toolbar"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
/>
<include
android:id="#+id/bottom_nav"
layout="#layout/bottom_menu_bar"
/>
bottom menu bar. xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/relativeLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_nav"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:menu="#menu/bottom_nav_menu" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/margin_padding"
android:src="#drawable/ic_add"
android:tint="#color/colorWhite"
app:backgroundTint="#color/colorPrimary"
app:layout_anchor="#id/bottom_nav"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:elevation="#dimen/floating_b_ele"
android:clickable="true"
android:focusable="true"
/>
</androidx.constraintlayout.widget.ConstraintLayout>

add a layout_marginBottom to the RecyclerView which is equal to the height of the bottom navigation

Shared Content overlapping Bottom Navigation

My MainActivity's got a RecyclerView and a BottomNavigationView. Items in the RecyclerView are CardViews.
When I click an item that's halfway obscured by the BottomNavigationView (- will call it BNV), it "pops" over the BNV, then slides up to become the header in LaunchedActivity.
When backing out of LaunchedActivity, it slides down, over the BNV, then "snaps" back into place:
How can I either:
Have the shared content appear to slide from underneath the BNV,
or failing that,
Have the shared content start off invisible, and fade as it slides to the header
I've tried playing with the elevation of the BNV, I've tried setting sharedElementEnterTransition to Fade(), I've tried specifying excludeTarget with BottomNavigation; I can't seem to make things work how I'd like.
Here's the layout for MainActivity:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<android.support.v7.widget.RecyclerView
android:id="#+id/rv"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toTopOf="#+id/bottomNavigationView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
/>
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottomNavigationView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/navigation"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
/>
</android.support.constraint.ConstraintLayout>
Activity_launched is here:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LaunchedActivity">
<android.support.design.widget.AppBarLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay"/>
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_launched"/>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
app:srcCompat="#android:drawable/ic_dialog_email"/>
</android.support.design.widget.CoordinatorLayout>
And content_launched:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/activity_launched"
tools:context=".LaunchedActivity">
<LinearLayout
android:id="#+id/launched_header"
android:transitionName="header" android:layout_width="0dp" android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent" app:layout_constraintStart_toStartOf="parent"
android:orientation="vertical" app:layout_constraintEnd_toEndOf="parent"
android:background="#android:color/holo_blue_bright"
android:layout_marginEnd="8dp">
<TextView
android:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/launched_title"/>
<TextView
android:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="#+id/launched_text"/>
</LinearLayout>
</android.support.constraint.ConstraintLayout>
Items in the RecyclerView call MainActivity.onItemClicked:
fun onItemClicked(view: View, item: Item) {
val intent = Intent(applicationContext, LaunchedActivity::class.java)
intent.putExtra("ITEM", item)
val options = ActivityOptions.makeSceneTransitionAnimation(
this,
android.util.Pair<View, String>(view, "header")
)
startActivity(intent, options.toBundle())
}
This is the array that's in the recycler:
data class Item(val title: String, val text: String): Serializable
val itemList = listOf(Item("One", "1"), Item("Two", "2"),
Item("Three", "3"), Item("Four", "4"), Item("Five", "5"))
Lastly, this is from LaunchedActivity.onCreate:
with(window) {
requestFeature(Window.FEATURE_CONTENT_TRANSITIONS)
requestFeature(Window.FEATURE_ACTIVITY_TRANSITIONS)
sharedElementEnterTransition = AutoTransition()
sharedElementExitTransition = AutoTransition()
}
LaunchedActivity.onCreate pulls the item out of the intent and sets launched_title and launched_text.

Add in recyclerView's item's CardView
app:cardMaxElevation="8dp"
and give your BNV
app:elevation="16dp"
give it a try, try with more difference in elevation as clicked cardview has more elevation than actual elevation

Have you heard of clipToPadding it can add padding to the bottom views so it does not obstruct the bottom views.
So try setting clipToPadding = "true" and check if it solves.
Android what does the clipToPadding Attribute do?
Also your layout activity file has <RecyclerView> set to 0dp.
Use a <RelativeLayout> outside and set layout_above="#bnv" in <RecyclerView> somewhat similar to this.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="#+id/navigation1"
android:layout_weight="1">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<com.nxtoff.plzcome.commonutills.BottomNavigationViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<View
android:layout_width="match_parent"
android:layout_height="0.5dp"
android:layout_below="#+id/viewpager"
android:background="#999999" />
</RelativeLayout>
</FrameLayout>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/navigation1"
android:layout_width="match_parent"
android:layout_height="56dp"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom"
android:background="?android:attr/windowBackground"
app:itemBackground="#android:color/white"
app:itemIconTint="#drawable/nav_item_colors"
app:itemTextColor="#drawable/nav_item_colors"
app:menu="#menu/navigation" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/xfb_fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_gravity="bottom|center_horizontal"
android:layout_margin="22dp"
android:layout_marginBottom="30dp"
android:background="#color/colorloader"
android:clickable="true"
android:src="#drawable/plus_fab"
android:tint="#color/colorviolet"
app:backgroundTint="#color/colorloader"
app:elevation="8dp"
app:fabSize="normal"
/>
</RelativeLayout>
EDIT 1:
Try out this code and let me know.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:layout_marginTop="8dp"
android:layout_above="#id/bottomNavigationView"
android:layout_alignParentTop="true"
android:layout_marginBottom="8dp"
/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottomNavigationView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/navigation"
android:layout_alignParentBottom="true"
/>
</RelativeLayout>

Bottom Navigation with fab

I am currently working with BottomNavigationView and FloatingActionButton.
What i want to achieve is this below design:
And what i have tried:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_insetEdge="bottom"
tools:context=".activity.BottomNavPrimary">
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center|bottom" />
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottomNavPrimary"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:layout_insetEdge="bottom"
android:background="?android:attr/windowBackground"
app:menu="#menu/bottom_nav_primary"></android.support.design.widget.BottomNavigationView>
</android.support.design.widget.CoordinatorLayout>

Your design looks as if you want to use the new BottomAppBar from the MaterialComponents that will fully be release with Android P. Especially if the left icon stands for a kind of side navigation it could be the right navigation element.
However, you have to be aware, that the elements on the left and right of the FAB have a different purpose than a bottom navigation. Instead of being entry points to "primary destinations" in an app, the BottomAppBar is defined as:
A bottom app bar displays navigation and key actions at the bottom of mobile screens.
So it is for page actions (like opening the dashboard or search). More explanation can be found in the design documentation.
I haven't had a chance to implement it yet (because I really needed it with a bottom navigation), but here is the code documentation example:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- Other components and views -->
<com.google.android.material.bottomappbar.BottomAppBar
android:id="#+id/bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:navigationIcon="#drawable/ic_menu_24"/>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_anchor="#id/bar"/>
</android.support.design.widget.CoordinatorLayout>
So to me, it sounds as if you define your two page menu options and since the FAB is anchored to the bar it will push them to the sides.
The documentation also includes options for the optional FAB cradle that was shown during this year's Google I/O and shows how to handle menu and click handling.
Here is another useful link on how to set up gradle to include the new material components in your project.

I used this, to get something similar.
BottomNavigationView + FloatingActionButton
<androidx.constraintlayout.widget.ConstraintLayout xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/floating_button"
style="#style/Widget.MaterialComponents.FloatingActionButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end"
android:layout_margin="16dp"
app:backgroundTint="#color/colorPrimaryLight"
app:elevation="#dimen/padding_10"
app:layout_constraintBottom_toTopOf="#id/navigation"
app:layout_constraintLeft_toRightOf="#id/navigation"
app:layout_constraintRight_toLeftOf="#id/navigation"
app:layout_constraintTop_toBottomOf="#id/navigation"
app:layout_constraintTop_toTopOf="#id/navigation"
app:layout_insetEdge="bottom"
app:srcCompat="#drawable/ic_add_black_24dp"
app:tint="#color/colorPrimary" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="#color/colorPrimaryDark"
android:visibility="visible"
app:itemIconTint="#drawable/bottom_navigation_icons"
app:itemTextColor="#drawable/bottom_navigation_icons"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:menu="#menu/navigation" />
</androidx.constraintlayout.widget.ConstraintLayout>

My solution simple and cool.
Parent layout must be a CoordinatorLayout and use BottomAppBar with FloatingActionButton as you can see below
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<-- your other views -->
<com.google.android.material.bottomappbar.BottomAppBar
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:backgroundTint="#color/colorPrimary">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<RelativeLayout
android:id="#+id/homePage"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintWidth_percent="0.4">
<androidx.appcompat.widget.AppCompatImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="#drawable/your_drawable"
android:padding="#dimen/small_margin"
app:tint="#color/white" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/profile"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintWidth_percent="0.4">
<androidx.appcompat.widget.AppCompatImageView
android:layout_width="wrap_content"
android:padding="#dimen/small_margin"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="#drawable/your_drawable" />
</RelativeLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
</com.google.android.material.bottomappbar.BottomAppBar>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/categories"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/your_drawable"
app:backgroundTint="#color/colorPrimary"
app:layout_anchor="#id/navigation"
app:tint="#android:color/white" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Result:

You could wrap your BottomNavigationView and your FloatingActionButton in a ConstraintLayout and use the following constraints on the FloatingActionButton:
app:layout_constraintTop_toBottomOf="#id/bottomNavPrimary"
app:layout_constraintBottom_toTopOf="#id/bottomNavPrimary"
app:layout_constraintLeft_toRightOf="#id/bottomNavPrimary"
app:layout_constraintRight_toLeftOf="#id/bottomNavPrimary"
This will center your FloatingActionButton vertically and horizontally relative to your BottomnavigationView
I hope that is what you asked for.
Final code would look something like this:
<android.support.design.widget.CoordinatorLayout android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<android.support.constraint.ConstraintLayout xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="#id/bottomNavPrimary"
app:layout_constraintBottom_toTopOf="#id/bottomNavPrimary"
app:layout_constraintLeft_toRightOf="#id/bottomNavPrimary"
app:layout_constraintRight_toLeftOf="#id/bottomNavPrimary"/>
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottomNavPrimary"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
app:layout_constraintBottom_toTopOf="parent"
android:background="?android:attr/windowBackground"
app:menu="#menu/bottom_nav_primary" />
</android.support.constraint.ConstraintLayout>

I think you can do this with bottomAppBar and embed some button inside that like below
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.bottomappbar.BottomAppBar
android:id="#+id/bottom_app_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:backgroundTint="#color/colorPrimary"
app:fabAlignmentMode="center"
app:fabAttached="true"
app:fabCradleDiameter="8dp"
style="#style/Widget.MaterialComponents.BottomAppBar"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<ImageButton
android:id="#+id/btnReport"
android:layout_width="0dp"
android:layout_height="match_parent"
android:background="#android:color/transparent"
android:src="#drawable/ic_play"
android:layout_weight="1"
android:paddingRight="20dp"
/>
<ImageButton
android:id="#+id/btnPlayWords"
android:layout_width="0dp"
android:layout_height="match_parent"
android:background="#android:color/transparent"
android:src="#drawable/ic_show_chart"
android:layout_weight="1"
android:paddingLeft="20dp"
/>
</LinearLayout>
</com.google.android.material.bottomappbar.BottomAppBar>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fabAddWord"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_add"
app:layout_anchor="#id/bottom_app_bar" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>