CounterView

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>  
    <declare-styleable name="IncDecView">
        <attr name="value" format="integer" />
        <attr name="type">
            <flag name="money" value="0" />
            <flag name="non-money" value="1" />
        </attr>
        <attr name="stepSize" format="integer" />
    </declare-styleable>
</resources>

counter_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/root_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/bg_outline"
    android:orientation="horizontal">

    <ImageButton
        android:id="@+id/button_dec"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@color/colorPrimary"
        android:padding="8dp"
        android:src="@drawable/ic_remove_white_24dp" />

    <RelativeLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_weight="9">

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/text_type"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:layout_marginEnd="16dp"
                android:layout_marginStart="16dp"
                android:text="@string/rupee_symbol"
                android:textColor="@color/grey"
                android:textSize="20sp" />

            <View
                android:id="@+id/view_type"
                android:layout_width="1dp"
                android:layout_height="20dp"
                android:layout_gravity="center"
                android:background="@color/grey" />
        </LinearLayout>

        <TextView
            android:id="@+id/text_value"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:layout_gravity="center"
            android:fontFamily="@font/verdana_ab"
            android:text="@string/_1_00_00_000"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/grey"
            android:textSize="14sp"
            android:textStyle="bold" />
    </RelativeLayout>

    <ImageButton
        android:id="@+id/button_inc"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="@color/colorPrimary"
        android:padding="8dp"
        android:src="@drawable/ic_add_white_24dp" />

</LinearLayout>

CounterView.kt

import android.content.Context
import android.util.AttributeSet
import android.view.View
import android.widget.LinearLayout
import kotlinx.android.synthetic.main.inc_dec_view.view.*

/**
 * Created by Bapusaheb Patil.
 */
class IncDecView : LinearLayout, View.OnClickListener {

    private var value: Int = 0
    private var stepSize: Int = 0
    private var type: Int? = 1
    private var listener: IncDecListener? = null

    constructor(ctx: Context?) : super(ctx) {
        initView(ctx, null, 0)
    }

    constructor(ctx: Context?, attrs: AttributeSet?) : super(ctx, attrs) {
        initView(ctx, attrs, 0)
    }

    constructor(ctx: Context?, attrs: AttributeSet?, defStyle: Int) : super(ctx, attrs, defStyle) {
        initView(ctx, attrs, defStyle)
    }

    private fun initView(ctx: Context?, attrs: AttributeSet?, defStyle: Int) {
        View.inflate(ctx, R.layout.inc_dec_view, this)
        this.button_inc.setOnClickListener(this)
        this.button_dec.setOnClickListener(this)
        if (attrs != null) {
            val attributes = context.theme.obtainStyledAttributes(attrs, R.styleable.IncDecView, defStyle, 0)
            this.value = attributes.getInt(R.styleable.IncDecView_value, 1000000)
            this.type = attributes.getInt(R.styleable.IncDecView_type, 1)
            this.stepSize = attributes.getInt(R.styleable.IncDecView_stepSize, 1)
            attributes.recycle()
        }
        updateUI(ctx)
    }

    private fun updateUI(ctx: Context?) {
        this.text_value.text = this.value.toString()
        when (this.type) {
            TYPE_MONEY -> {
                this.text_type.text = ctx?.getString(R.string.rupee_symbol)
            }
            else -> {
                this.text_type.visibility = View.GONE
                this.view_type.visibility = View.GONE
            }
        }
    }

    override fun onClick(v: View?) {
        var textViewValue = this.text_value.text.toString().toInt()
        when (v?.id) {
            R.id.button_inc -> {
                textViewValue += this.stepSize
                this.value = textViewValue
                this.text_value.text = textViewValue.toString()
                this.listener?.onIncClick(this.text_value.text.toString().toInt())
            }
            R.id.button_dec -> {
                textViewValue -= this.stepSize
                if (textViewValue < 1)
                    textViewValue = 1
                this.value = textViewValue
                this.text_value.text = textViewValue.toString()
                this.listener?.onDecClick(this.text_value.text.toString().toInt())
            }
        }
    }

    fun setCounterListener(incDecListener: IncDecListener): IncDecView {
        this.listener = incDecListener
        return this
    }

    interface IncDecListener {
        fun onIncClick(value: Int)
        fun onDecClick(value: Int)
    }

    companion object {
        const val TYPE_MONEY = 0
        const val TYPE_NON_MONEY = 1
    }

}