Add tutorial for simple MVC lists

Change-Id: I2a049b3c8ad7ed50b478d6ba2f8aded22544a307
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1628989Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#664796}

docs/ui/android/mvc_architecture_tutorial.md

@@ -6,6 +6,7 @@ A full explanation of the MVC framework can be found [here](https://docs.google.
 For this example, we’ll be implementing a simple progress bar; a rectangle that changes length based on the loading state of the underlying webpage.
 
 #### Additional Resources
+[Simple MVC lists](https://chromium.googlesource.com/chromium/src/+/HEAD/docs/ui/android/mvc_simple_list_tutorial.md)
 [Testing MVC primer doc](https://docs.google.com/document/d/1Mel7f4lE_osFjnttkxu1wcUf_k9CmIzPv6oxwCw9tx4/edit#)
 
 #### File Structure

docs/ui/android/mvc_simple_list_tutorial.md

+# Simple Lists in MVC Land
+
+### Overview
+This tutorial is intended to go over a basic implementation of lists in the Chrome on Android MVC
+framework. If you're not sure what MVC is, see [Additional Resources](#Additional-Resources).
+
+In this example we'll be creating a simple menu list where each list item consists of an icon and
+label.
+
+### Additional Resources
+[Introductory MVC tutorial][mvc_tutorial_link]
+
+#### Todo
+[Update this doc to use data providers](https://crbug.com/967054)
+
+### File Structure
+The file structure of our component will be the following:
+* ./chrome/android/java/src/org/chromium/chrome/browser/simple_menu/
+  * [`SimpleMenuCoordinator.java`](#SimpleMenuCoordinator)
+  * [`SimpleMenuItemViewBinder.java`](#SimpleMenuItemViewBinder)
+  * [`SimpleMenuProperties.java`](#SimpleMenuProperties)
+* ./chrome/android/java/res/layout/
+  * [`simple_menu_item.xml`](#simple_menu_item_xml)
+
+### SimpleMenuCoordinator
+This class will own the ListAdapter that knows how to show PropertyModels. In this example we'll be
+combining the responsibilities of what would otherwise be the coordinator and mediator for
+simplicity.
+
+```java
+public class SimpleMenuCoordinator {
+
+    public SimpleMenuCoordinator(Context context, ListView listView) {
+        ModelListAdapter adapter = new ModelListAdapter(context);
+
+        final LayoutInflater layoutInflater = context.getSystemService(LAYOUT_INFLATER_SERVICE);
+
+        // If this is a heterogeneous list, register more than one type.
+        adapter.registerType(
+                ListItemType.DEFAULT,
+                () -> layoutInflater.inflate(R.layout.simple_menu_item, null),
+                SimpleMenuItemViewBinder::bind);
+
+        listView.setAdapter(adapter);
+
+        List<Pair<Integer, PropertyModel>> items = new ArrayList<>();
+        PropertyModel listModel1 = generateListItem(
+                ApiCompatibilityUtils.getDrawable(context.getResources(), R.drawable.icon),
+                context.getResources().getString(R.string.label));
+        // The list adapter needs to be told what kind of view should render the data; hence the
+        // pair object.
+        list.add(new Pair(ListItemType.DEFAULT, listModel1));
+
+        // ... add other list items as needed. Typically this work is done in the mediator piece of
+        // the component.
+
+        adapter.updateModels(items);
+    }
+
+    public PropertyModel generateListItem(Drawable icon, String text) {
+        return PropertyModel.Builder(SimpleMenuProperties.ALL_KEYS)
+                .with(SimpleMenuProperties.ICON, icon)
+                .with(SimpleMenuProperties.LABEL, text)
+                .with(SimpleMenuProperties.CLICK_LISTENER, (view) -> handleClick(view))
+                .build();
+        // Click handling can be done as above or the listener can be passed in.
+    }
+
+    private void handleClick(View view) {
+        // Do some click logic here. This would typically be done in the mediator.
+    }
+}
+```
+
+### SimpleMenuProperties
+These are the types of data that we want to apply to each list item in our menu.
+```java
+class SimpleMenuProperties {
+    @IntDef({ListItemType.DEFAULT})
+    @Retention(RetentionPolicy.SOURCE)
+    /**
+     * This can be one or more items depending on if the list is homogeneous. If homogeneous,
+     * this definition can be skipped and 0 can be used in place of that parameter.
+     */
+    public @interface ListItemType {
+        int DEFAULT = 0;
+    }
+
+    /** The icon for the list item. */
+    public static final WritableObjectPropertyKey<Drawable> ICON =
+            new WritableObjectPropertyKey<>();
+
+    /** The text shown next to the icon. */
+    public static final WritableObjectPropertyKey<String> LABEL =
+            new WritableObjectPropertyKey<>();
+
+    /** The action that occurs when the list item is tapped. */
+    public static final WritableObjectPropertyKey<OnClickListener> CLICK_LISTENER =
+            new WritableObjectPropertyKey<>();
+
+    public static final PropertyKey[] ALL_KEYS = {ICON, LABEL, CLICK_LISTENER};
+}
+```
+
+### SimpleMenuItemViewBinder
+As per the MVC architecture, this class is responsible for taking a model and applying that
+information in to to a provided view.
+```java
+class SimpleMenuItemViewBinder {
+
+    // This can optionally be in the coordinator file depending on the complexity.
+    public static void bind(PropertyModel model, View view, PropertyKey propertyKey) {
+        if (SimpleMenuProperties.ICON == propertyKey) {
+            ((ImageView) view.findViewById(R.id.simple_menu_icon)).setImageDrawable(
+                    model.get(SimpleMenuProperties.ICON));
+
+        } else if (SimpleMenuProperties.LABEL == propertyKey) {
+            ((TextView) view.findViewById(R.id.simple_menu_label)).setText(
+                    model.get(SimpleMenuProperties.LABEL));
+
+        } else if (SimpleMenuProperties.CLICK_LISTENER == propertyKey) {
+            view.setOnClickListener(model.get(SimpleMenuProperties.CLICK_LISTENER));
+        }
+    }
+
+}
+```
+
+### simple_menu_item.xml
+```xml
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2019 The Chromium Authors. All rights reserved.
+     Use of this source code is governed by a BSD-style license that can be
+     found in the LICENSE file. -->
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="horizontal"
+    android:background="@color/modern_primary_color">
+
+    <org.chromium.ui.widget.ChromeImageView
+        android:id="@+id/simple_menu_icon"
+        android:layout_width="18dp"
+        android:layout_height="18dp"
+        android:layout_gravity="center_vertical"
+        android:scaleType="centerInside"/>
+
+    <TextView
+        android:id="@+id/simple_menu_label"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:gravity="center_vertical"
+        android:textAppearance="@style/TextAppearance.BlackBody"/>
+
+</LinearLayout>
+```
+
+[mvc_tutorial_link]:https://chromium.googlesource.com/chromium/src/+/HEAD/docs/ui/android/mvc_architecture_tutorial.md
+