Android - How to change bottom navigation bar text's font family

Question

I have created a bottom bar navigation in my android page. But now I want to apply the custom font-family in bottom navigation texts.

This is the bottom navigation c

Answer 1

Kotlin language:

1: Create a file with a custom name, ex: BottomNavigationViewExtension.kt

2: Put the code below:

import android.graphics.Typeface
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import com.google.android.material.bottomnavigation.BottomNavigationView

fun BottomNavigationView.changeNavTypeface(typeface: Typeface) {
    val view: View = this
    checker(view, typeface)

}
private fun checker(view: View, typeface: Typeface) {
    if (view is ViewGroup) {
        for (i in 0 until view.childCount) {
            val child = view.getChildAt(i)
            checker(child, typeface)
        }
    } else if (view is TextView) {
        view.typeface = typeface
    }
}

3: Usage:

navView.changeNavTypeface(
    Typeface.createFromAsset(
        assets,
        "fonts/IRANSansMobile.ttf"
    )
)