Custom Font with attributes

CTextView.java

package com.pay.app.controls

import android.content.Context
import android.content.res.TypedArray
import android.graphics.Typeface
import android.util.AttributeSet
import androidx.appcompat.widget.AppCompatTextView
import com.pay.app.R


class CTextView : AppCompatTextView {
    constructor(context: Context, attrs: AttributeSet) : super(
        context,
        attrs
    ) {
        applyCustomFont(context, attrs)
    }

    constructor(
        context: Context,
        attrs: AttributeSet,
        defStyle: Int
    ) : super(context, attrs, defStyle) {
        applyCustomFont(context, attrs)
    }

    private fun applyCustomFont(
        context: Context,
        attrs: AttributeSet
    ) {

        val a: TypedArray = context.obtainStyledAttributes(attrs, R.styleable.font)
        val customFont = a.getString(R.styleable.font_customFont)
        var tf: Typeface? = null
        tf = try {
            Typeface.createFromAsset(context.assets, customFont)
        } catch (e: Exception) {
            Typeface.createFromAsset(context.assets, "sf_pro_text_bold.ttf")
        }
        typeface = tf
        a.recycle()
        isAllCaps = false
    }

    companion object {
        const val ANDROID_SCHEMA = "http://schemas.android.com/apk/res/android"
    }
}

==================================
attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="font">
        <attr name="customFont" format="string" />
    </declare-styleable>
</resources>

===================================
app:customFont="@string/montserrat_semibold"