Using Android sample data `tools:showIn`, `tools:listitem`, `tools:...="@sample/data.json` for awesome layout preview

src-main-res-layout-mylistitem.xml

<?xml version="1.0" encoding="utf-8"?>

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
                                             xmlns:app="http://schemas.android.com/apk/res-auto"
                                             xmlns:tools="http://schemas.android.com/tools"
                                             android:layout_width="match_parent"
                                             android:layout_height="wrap_content"
                                             tools:showIn="@layout/myscreen">

    <ImageView
        android:id="@+id/icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="12dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:srcCompat="@sample/mydata.json/items/icon"
        tools:tint="@sample/mydata.json/items/icon_color"/>

    <TextView
        android:id="@+id/label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintStart_toEndOf="@+id/icon"
        app:layout_constraintTop_toTopOf="parent"
        tools:text="@sample/mydata.json/items/label"/>
</android.support.constraint.ConstraintLayout>

src-main-res-layout-myscreen.xml

<?xml version="1.0" encoding="utf-8"?>

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
                                             xmlns:app="http://schemas.android.com/apk/res-auto"
                                             xmlns:tools="http://schemas.android.com/tools"
                                             android:layout_width="match_parent"
                                             android:layout_height="match_parent">

    <android.support.v7.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:listitem="@layout/mylistitem"/>
</android.support.constraint.ConstraintLayout>

src-main-sampledata-mydata.json

{
  "items": [
    {
      "label": "Foo",
      "icon": "@drawable/ic_android_black_24dp",
      "icon_color": "#ff0000"
    },
    {
      "label": "Bar",
      "icon": "@drawable/ic_star_black_24dp",
      "icon_color": "#ffff00"
    },
    {
      "label": "Zorg",
      "icon": "@drawable/ic_account_circle_black_24dp",
      "icon_color": "#ff00ff"
    },
    {
      "label": "Quux",
      "icon": "@drawable/ic_brush_black_24dp",
      "icon_color": "#00ffff"
    },
    {
      "label": "Garply",
      "icon": "@drawable/ic_child_care_black_24dp",
      "icon_color": "#0000ff"
    }
  ]
}

More details here: https://speakerdeck.com/camaelon/design-tools-and-constraintlayout?slide=79 and there https://developer.android.com/studio/write/tool-attributes.html