How to change selected BottomNavigationView icon size

Question

I am using native BottomNavigationView and I want to change selected icon size bigger than unselected icon sizes. (exp. selected icon 40dp, other icon sizes 20dp).

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottom_navigation"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_alignParentBottom="true"
        android:layout_centerVertical="true"
        android:scaleType="center"
        style="@style/Widget.Design.BottomNavigationView"
        app:labelVisibilityMode="unlabeled"
        app:menu="@menu/navigation_menu" />

<item
    android:id="@+id/homePageFragment"
    android:icon="@drawable/selector_nav_home"
    android:orderInCategory="1"
    android:title="" />

<item
    android:id="@+id/discoverPageFragment"
    android:icon="@drawable/selector_nav_discover"
    android:orderInCategory="2"
    android:title="" />

<item
    android:id="@+id/qrPageFragment"
    android:icon="@drawable/selector_nav_qr"
    android:orderInCategory="3"
    android:title="" />

<item
    android:id="@+id/myAccountFragment"
    android:icon="@drawable/selector_nav_profile"
    android:orderInCategory="4"
    android:title="" />

<item android:drawable="@drawable/ic_bottom_navigation_profile" android:state_checked="true"/>

<item android:drawable="@drawable/ic_navigation_profile" android:state_checked="false"/>

Maybe this could help you: https://stackoverflow.com/questions/41516568/changing-bottomnavigationviews-icon-size — Lukas, Dec 22 '19 at 21:57
You can use large size of ic_bottom_navigation_profile then ic_navigation_profile — Nidhi Savaliya, Dec 23 '19 at 04:35

score 3 · Answer 1 · answered Nov 11 '20 at 12:22

You can change text size of selected item like this:

styles.xml:

<style name="bottomNavigationView.Active" parent="@style/TextAppearance.AppCompat.Caption">
        <item name="android:textSize">16sp</item>
</style>

bottom_navigation_view.xml:

<?xml version="1.0" encoding="utf-8"?>
<com.google.android.material.bottomnavigation.BottomNavigationView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/bottomNavView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?android:attr/windowBackground"
    app:menu="@menu/bottom_nav_menu"
    app:labelVisibilityMode="labeled"
    app:itemIconSize="24dp"
    android:scaleType="center"
    app:itemTextAppearanceActive="@style/bottomNavigationView.Active" />

As a result of increased text size the selected item's icon lifts up and as a whole this looks like the selected element was increased in size:

like this

score 0 · Answer 2 · answered Jun 01 '21 at 14:49

Try this to change the selected item icon size

override fun onNavigationItemSelected(item: MenuItem): Boolean {
    changeItemIconSize(item.itemId)
    return true
}     

private fun changeItemIconSize(selectedItemId: Int) {
    val displayMetrics = resources.displayMetrics
    val menuView = bottomMenu.getChildAt(0) as BottomNavigationMenuView
    bottomMenu.itemIconSize = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 24f, displayMetrics).toInt()
    val iconViewSelected =
        menuView.findViewById<View>(selectedItemId).findViewById<View>(com.google.android.material.R.id.icon)
    val layoutParams = iconViewSelected.layoutParams
    layoutParams.height =
        TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 32f, displayMetrics).toInt()
    layoutParams.width =
        TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 32f, displayMetrics).toInt()
    iconViewSelected.layoutParams = layoutParams
}

How to change selected BottomNavigationView icon size

2 Answers2