attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="ProgressStepperView">
        <attr name="sl_line_color" format="color"/>
        <attr name="sl_line_width" format="dimension"/>

        <attr name="sl_title_text_color" format="color"/>
        <attr name="sl_subtitle_text_color" format="color"/>

        <attr name="sl_icon_size" format="dimension"/>
        <attr name="sl_icon_horizontal_spacing" format="dimension"/>

        <attr name="sl_font" format="reference"/>
        <attr name="sl_title_text_size" format="dimension"/>
        <attr name="sl_subtitle_text_size" format="dimension"/>

        <attr name="sl_vertical_spacing" format="dimension"/>

        <attr name="sl_icon_ok" format="reference"/>
        <attr name="sl_icon_pending" format="reference"/>

    </declare-styleable>
</resources>

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="sl_title_text_color">#2a7bbf</color>
    <color name="sl_title_pending_text_color">#8b8b8b</color>
    <color name="sl_line_color">#e8e8e8</color>
    <color name="sl_subtitle_text_color">#8b8b8b</color>
    <color name="sl_subtitle_pending_text_color">#8b8b8b</color>
    <color name="sl_pending_border_bg_color">#d6d6d6</color>
    <color name="sl_pending_bg_color">#f8fcff</color>
    <color name="sl_check_color">#fff</color>
    <color name="sl_check_bg_color">#2a7bbf</color>
</resources>

Stepper.kt

package br.com.concrete.stepper

import android.content.Context
import android.graphics.Canvas
import android.graphics.Paint
import android.graphics.drawable.Drawable
import android.support.annotation.AttrRes
import android.support.annotation.ColorInt
import android.support.annotation.Dimension
import android.support.v7.content.res.AppCompatResources
import android.util.AttributeSet
import android.util.TypedValue
import android.view.View
import android.view.ViewGroup.LayoutParams.MATCH_PARENT
import android.view.ViewGroup.LayoutParams.WRAP_CONTENT
import android.widget.LinearLayout
import android.widget.TextView

data class ProgressItem(
    val title: CharSequence,
    val subtitle: CharSequence?,
    val pending: Boolean
)

class ProgressStepperView @JvmOverloads constructor(
    context: Context,
    attrs: AttributeSet? = null,
    defStyleAttr: Int = 0
) : LinearLayout(context, attrs, defStyleAttr) {

    private val items = mutableListOf<ProgressItem>()

    private val defaultIconSize = context.resolveDimension(R.attr.sl_icon_size)
    private val defaultLineWidth = context.resolveDimension(R.attr.sl_line_width)
    private val defaultLineColor = context.resolveColor(R.attr.sl_line_color)
    private val defaultIconHorizontalSpace = context.resolveDimension(R.attr.sl_icon_horizontal_spacing)
    private val defaultVerticalSpace = context.resolveDimension(R.attr.sl_vertical_spacing)
    private val iconCheck = context.resolveDrawable(R.attr.sl_icon_ok)
    private val iconPending = context.resolveDrawable(R.attr.sl_icon_pending)

    private val linePaint = Paint().apply {
        strokeWidth = defaultLineWidth.toFloat()
        isAntiAlias = true
        color = defaultLineColor
    }

    override fun onFinishInflate() {
        super.onFinishInflate()
        setWillNotDraw(false)
        orientation = VERTICAL
        iconCheck.setBounds(0, 0, defaultIconSize, defaultIconSize)
        iconPending.setBounds(0, 0, defaultIconSize, defaultIconSize)

        if (isInEditMode) {
            addItem(ProgressItem("Title 1", "Subtitle 1", false))
            addItem(ProgressItem("Title 2", "Subtitle 2", false))
        }
    }

    override fun onDraw(canvas: Canvas) {
        super.onDraw(canvas)
        if (items.isEmpty()) return

        if (items.size > 1) {
            val first = getChildAt(0)
            val last = getChildAt(childCount - 1)

            drawVerticalLine(
                canvas,
                first.y + defaultIconSize / 2,
                last.y + defaultIconSize / 2
            )
        }

        items.forEachIndexed { index, it ->
            val view = getChildAt(index)
            drawIcon(canvas, view.y, it)
        }
    }

    fun addItem(item: ProgressItem) {
        val view = createView(item)
        addViewToThis(view)
        items.add(item)
        invalidate()
    }

    private fun createView(item: ProgressItem): View {
        val view = View.inflate(context, R.layout.view_step_title, null)
        view.minimumHeight = defaultIconSize

        val title = view.findViewById<TextView>(R.id.textViewTitle)
        val subtitle = view.findViewById<TextView>(R.id.textViewSubtitle)

        title.text = item.title
        title.isEnabled = !item.pending

        item.subtitle?.let {
            subtitle.visibility = View.VISIBLE
            subtitle.text = it
            title.isEnabled = !item.pending
        }

        return view
    }

    private fun drawVerticalLine(canvas: Canvas, yFirst: Float, yLast: Float) {

        val x = paddingStart + defaultIconSize / 2f
        canvas.save()
        canvas.translate(x, 0f)
        canvas.drawLine(0f, yFirst, 0f, yLast, linePaint)
        canvas.restore()
    }

    private fun drawIcon(canvas: Canvas, startY: Float, item: ProgressItem) {
        canvas.save()
        canvas.translate(paddingStart.toFloat(), startY)

        if (item.pending)
            iconPending.draw(canvas)
        else
            iconCheck.draw(canvas)

        canvas.restore()
    }

    private fun addViewToThis(view: View) {

        val xStart = defaultIconSize + defaultIconHorizontalSpace

        addView(view.apply {
            layoutParams = LinearLayout.LayoutParams(MATCH_PARENT, WRAP_CONTENT).apply {
                marginStart = xStart
                if (items.size > 0)
                    topMargin = defaultVerticalSpace
            }
        })
    }
}

@ColorInt
private fun Context.resolveColor(@AttrRes attributeColor: Int): Int {
    val typedValue = TypedValue()
    theme.resolveAttribute(attributeColor, typedValue, true)
    return typedValue.data
}

@Dimension
private fun Context.resolveDimension(@AttrRes attributeDimen: Int): Int {
    val typedValue = TypedValue()
    theme.resolveAttribute(attributeDimen, typedValue, true)
    val attributes = intArrayOf(attributeDimen)
    val typedArray = obtainStyledAttributes(typedValue.data, attributes)
    val res = typedArray.getDimensionPixelSize(0, 0)
    typedArray.recycle()
    return res
}

@Dimension
private fun Context.resolveDrawable(@AttrRes attributeDimen: Int): Drawable {
    val typedValue = TypedValue()
    theme.resolveAttribute(attributeDimen, typedValue, true)
    return AppCompatResources.getDrawable(this, typedValue.resourceId)!!
}

styles.xml

<resources>

    <style name="Stepper" parent="Theme.AppCompat">
        <item name="sl_title_text_color">@color/title_text_color</item>
        <item name="sl_subtitle_text_color">@color/subtitle_text_color</item>
        <item name="sl_line_color">@color/sl_line_color</item>
        <item name="sl_icon_horizontal_spacing">10dp</item>
        <item name="sl_vertical_spacing">12dp</item>
        <item name="sl_icon_ok">@drawable/ic_step_ok</item>
        <item name="sl_icon_pending">@drawable/ic_step_pending</item>
    </style>

    <style name="Stepper.Small">
        <item name="sl_line_width">9dp</item>
        <item name="sl_icon_size">20dp</item>
        <item name="sl_title_text_size">14sp</item>
        <item name="sl_subtitle_text_size">12sp</item>
    </style>

    <style name="Stepper.Large">
        <item name="sl_line_width">15dp</item>
        <item name="sl_icon_size">30dp</item>
        <item name="sl_title_text_size">24sp</item>
        <item name="sl_subtitle_text_size">16sp</item>
    </style>

</resources>

subtitle_text_color.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/sl_subtitle_pending_text_color" android:state_enabled="false"/>
    <item android:color="@color/sl_subtitle_text_color"/>
</selector>

title_text_color.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/sl_title_pending_text_color" android:state_enabled="false"/>
    <item android:color="@color/sl_title_text_color"/>
</selector>

view_step_title.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:tools="http://schemas.android.com/tools"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:orientation="vertical">

    <TextView
            android:id="@+id/textViewTitle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:includeFontPadding="false"
            android:textColor="?attr/sl_title_text_color"
            android:textSize="?attr/sl_title_text_size"
            android:fontFamily="?attr/sl_font"
            android:gravity="start"
            tools:text="Pedido recebido"/>

    <TextView
            android:id="@+id/textViewSubtitle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:includeFontPadding="false"
            android:textColor="?attr/sl_subtitle_text_color"
            android:textSize="?attr/sl_subtitle_text_size"
            android:fontFamily="?attr/sl_font"
            android:visibility="gone"
            tools:visibility="visible"
            tools:text="Entrega em 04/04/2018"
    />

</LinearLayout>