[SetupWizardLib] Add support for require scrolling

Add SetupWizardLayout.requireScrollToBottom method that will register
a RequireScrollHelper on the layout. When the helper is registered
and the content view can scroll, the next button will be hidden and a
down-arrow button is shown, which will scroll the page down when
clicked.

Change-Id: Ib9ddcbeec24169cc00265fe107deb1b5099cba8d

library/eclair-mr1/res/drawable/suw_navbar_ic_more_dark.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright (C) 2015 The Android Open Source Project
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+
+<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
+    android:src="@drawable/suw_navbar_ic_down_arrow_dark" />

library/eclair-mr1/res/drawable/suw_navbar_ic_more_light.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright (C) 2015 The Android Open Source Project
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+
+<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
+    android:src="@drawable/suw_navbar_ic_down_arrow_light" />

library/eclair-mr1/res/values/styles.xml

@@ -86,6 +86,7 @@
         <item name="suwNavBarBackButton">@drawable/suw_navbar_ic_back_dark</item>
         <item name="suwNavBarBackgroundColor">@color/suw_navbar_bg_dark</item>
         <item name="suwNavBarButtonBackground">@drawable/suw_navbar_btn_bg_dark</item>
+        <item name="suwNavBarMoreButton">@drawable/suw_navbar_ic_more_dark</item>
         <item name="suwNavBarNextButton">@drawable/suw_navbar_ic_next_dark</item>
         <item name="suwNavBarTextColor">@color/suw_navbar_text_dark</item>
     </style>
@@ -94,6 +95,7 @@
         <item name="suwNavBarBackButton">@drawable/suw_navbar_ic_back_light</item>
         <item name="suwNavBarBackgroundColor">@color/suw_navbar_bg_light</item>
         <item name="suwNavBarButtonBackground">@drawable/suw_navbar_btn_bg_light</item>
+        <item name="suwNavBarMoreButton">@drawable/suw_navbar_ic_more_light</item>
         <item name="suwNavBarNextButton">@drawable/suw_navbar_ic_next_light</item>
         <item name="suwNavBarTextColor">@color/suw_navbar_text_light</item>
     </style>

library/main/res/drawable-v21/suw_navbar_ic_more.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright (C) 2015 The Android Open Source Project
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+-->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="@dimen/suw_navbar_ic_intrinsic_size"
+    android:height="@dimen/suw_navbar_ic_intrinsic_size"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+
+    <path
+        android:fillColor="?attr/suwNavBarTextColor"
+        android:pathData="M16.6,8.6l-4.6,4.6 -4.6,-4.6 -1.4,1.4 6,6 6,-6z"/>
+
+</vector>

library/main/res/layout/suw_navbar_view.xml

@@ -32,6 +32,17 @@
         android:layout_weight="1"
         android:visibility="invisible" />
 
+    <view class="com.android.setupwizardlib.view.NavigationBar$NavButton"
+        android:id="@+id/suw_navbar_more"
+        style="@style/SuwNavBarButtonStyle"
+        android:layout_width="wrap_content"
+        android:layout_height="match_parent"
+        android:contentDescription="@string/suw_more_button_label"
+        android:drawableEnd="?attr/suwNavBarMoreButton"
+        android:drawableRight="?attr/suwNavBarMoreButton"
+        android:gravity="end|center_vertical"
+        android:visibility="gone" />
+
     <view class="com.android.setupwizardlib.view.NavigationBar$NavButton"
         android:id="@+id/suw_navbar_next"
         style="@style/SuwNavBarButtonStyle"

library/main/res/values-v21/styles.xml

@@ -54,6 +54,7 @@
         <item name="suwNavBarBackButton">@drawable/suw_navbar_ic_back</item>
         <item name="suwNavBarBackgroundColor">@color/suw_navbar_bg_dark</item>
         <item name="suwNavBarButtonBackground">@drawable/suw_navbar_btn_bg</item>
+        <item name="suwNavBarMoreButton">@drawable/suw_navbar_ic_more</item>
         <item name="suwNavBarNextButton">@drawable/suw_navbar_ic_next</item>
         <item name="suwNavBarTextColor">@color/suw_navbar_text_dark</item>
     </style>
@@ -62,6 +63,7 @@
         <item name="suwNavBarBackButton">@drawable/suw_navbar_ic_back</item>
         <item name="suwNavBarBackgroundColor">@color/suw_navbar_bg_light</item>
         <item name="suwNavBarButtonBackground">@drawable/suw_navbar_btn_bg</item>
+        <item name="suwNavBarMoreButton">@drawable/suw_navbar_ic_more</item>
         <item name="suwNavBarNextButton">@drawable/suw_navbar_ic_next</item>
         <item name="suwNavBarTextColor">@color/suw_navbar_text_light</item>
     </style>

library/main/res/values/attrs.xml

@@ -23,6 +23,7 @@
     <attr name="suwNavBarBackButton" format="reference" />
     <attr name="suwNavBarBackgroundColor" format="color" />
     <attr name="suwNavBarButtonBackground" format="color|reference" />
+    <attr name="suwNavBarMoreButton" format="reference" />
     <attr name="suwNavBarNextButton" format="reference" />
     <attr name="suwNavBarTextColor" format="color" />
     <attr name="suwNavBarTheme" format="reference" />

library/main/res/values/strings.xml

@@ -16,9 +16,12 @@
 -->
 
 <resources>
-    <!-- Button for going to the next screen or step [CHAR LIMIT=40] -->
+    <!-- Button for going to the next screen or step [CHAR LIMIT=20] -->
     <string name="suw_next_button_label">Next</string>
 
-    <!-- Button for going to the previous screen or step [CHAR LIMIT=40] -->
+    <!-- Button for going to the previous screen or step [CHAR LIMIT=20] -->
     <string name="suw_back_button_label">Back</string>
+
+    <!-- Button for scrolling down to reveal more content on the screen [CHAR LIMIT=20] -->
+    <string name="suw_more_button_label">More</string>
 </resources>

library/main/src/com/android/setupwizardlib/SetupWizardLayout.java

@@ -29,6 +29,7 @@ import android.os.Build.VERSION_CODES;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.util.AttributeSet;
+import android.util.Log;
 import android.util.TypedValue;
 import android.view.Gravity;
 import android.view.LayoutInflater;
@@ -38,6 +39,8 @@ import android.view.ViewStub;
 import android.widget.FrameLayout;
 import android.widget.TextView;
 
+import com.android.setupwizardlib.util.RequireScrollHelper;
+import com.android.setupwizardlib.view.BottomScrollView;
 import com.android.setupwizardlib.view.Illustration;
 import com.android.setupwizardlib.view.NavigationBar;
 
@@ -222,6 +225,22 @@ public class SetupWizardLayout extends FrameLayout {
         return view instanceof NavigationBar ? (NavigationBar) view : null;
     }
 
+    private BottomScrollView getScrollView() {
+        final View view = findViewById(R.id.suw_bottom_scroll_view);
+        return view instanceof BottomScrollView ? (BottomScrollView) view : null;
+    }
+
+    public void requireScrollToBottom() {
+        final NavigationBar navigationBar = getNavigationBar();
+        final BottomScrollView scrollView = getScrollView();
+        if (navigationBar != null && scrollView != null) {
+            RequireScrollHelper.requireScroll(navigationBar, scrollView);
+        } else {
+            Log.e(TAG, "Both suw_layout_navigation_bar and suw_bottom_scroll_view must exist in"
+                    + " the template to require scrolling.");
+        }
+    }
+
     public void setHeaderText(int title) {
         final TextView titleView = (TextView) findViewById(R.id.suw_layout_title);
         if (titleView != null) {

library/main/src/com/android/setupwizardlib/util/RequireScrollHelper.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.setupwizardlib.util;
+
+import android.view.View;
+import android.widget.ScrollView;
+
+import com.android.setupwizardlib.view.BottomScrollView;
+import com.android.setupwizardlib.view.NavigationBar;
+
+/**
+ * Add this helper to require the scroll view to be scrolled to the bottom, making sure that the
+ * user sees all content on the screen. This will change the navigation bar to show the more button
+ * instead of the next button when there is more content to be seen. When the more button is
+ * clicked, the scroll view will be scrolled one page down.
+ */
+public class RequireScrollHelper implements BottomScrollView.BottomScrollListener,
+        View.OnClickListener {
+
+    /**
+     * Require scrolling on the scrollView, so that if the scrollView has content hidden beneath the
+     * fold, the next button will be hidden and the more button will be shown instead. The more
+     * button will scroll the scrollView downwards when clicked until the bottom is reached.
+     *
+     * @param navigationBar The navigation bar in which the next button's label will be changed.
+     * @param scrollView The {@link BottomScrollView} to be scrolled.
+     */
+    public static RequireScrollHelper requireScroll(NavigationBar navigationBar,
+            BottomScrollView scrollView) {
+        final RequireScrollHelper helper = new RequireScrollHelper(navigationBar, scrollView);
+        helper.requireScroll();
+        return helper;
+    }
+
+    private final BottomScrollView mScrollView;
+    private final NavigationBar mNavigationBar;
+
+    private boolean mScrollNeeded;
+
+    private RequireScrollHelper(NavigationBar navigationBar, BottomScrollView scrollView) {
+        mNavigationBar = navigationBar;
+        mScrollView = scrollView;
+    }
+
+    private void requireScroll() {
+        mNavigationBar.getMoreButton().setOnClickListener(this);
+        mScrollView.setBottomScrollListener(this);
+    }
+
+    @Override
+    public void onScrolledToBottom() {
+        if (mScrollNeeded) {
+            mNavigationBar.getNextButton().setVisibility(View.VISIBLE);
+            mNavigationBar.getMoreButton().setVisibility(View.GONE);
+            mScrollNeeded = false;
+        }
+    }
+
+    @Override
+    public void onRequiresScroll() {
+        if (!mScrollNeeded) {
+            mNavigationBar.getNextButton().setVisibility(View.GONE);
+            mNavigationBar.getMoreButton().setVisibility(View.VISIBLE);
+            mScrollNeeded = true;
+        }
+    }
+
+    @Override
+    public void onClick(View view) {
+        mScrollView.pageScroll(ScrollView.FOCUS_DOWN);
+    }
+}

library/main/src/com/android/setupwizardlib/view/NavigationBar.java

@@ -68,6 +68,7 @@ public class NavigationBar extends LinearLayout implements View.OnClickListener
 
     private Button mNextButton;
     private Button mBackButton;
+    private Button mMoreButton;
     private NavigationBarListener mListener;
 
     public NavigationBar(Context context) {
@@ -92,6 +93,7 @@ public class NavigationBar extends LinearLayout implements View.OnClickListener
         View.inflate(getContext(), R.layout.suw_navbar_view, this);
         mNextButton = (Button) findViewById(R.id.suw_navbar_next);
         mBackButton = (Button) findViewById(R.id.suw_navbar_back);
+        mMoreButton = (Button) findViewById(R.id.suw_navbar_more);
     }
 
     public Button getBackButton() {
@@ -102,6 +104,10 @@ public class NavigationBar extends LinearLayout implements View.OnClickListener
         return mNextButton;
     }
 
+    public Button getMoreButton() {
+        return mMoreButton;
+    }
+
     public void setNavigationBarListener(NavigationBarListener listener) {
         mListener = listener;
         if (mListener != null) {

library/test/src/com/android/setupwizardlib/test/RequireScrollHelperTest.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.setupwizardlib.test;
+
+import android.content.Context;
+import android.test.AndroidTestCase;
+import android.test.suitebuilder.annotation.SmallTest;
+import android.view.View;
+
+import com.android.setupwizardlib.util.RequireScrollHelper;
+import com.android.setupwizardlib.view.BottomScrollView;
+import com.android.setupwizardlib.view.NavigationBar;
+
+public class RequireScrollHelperTest extends AndroidTestCase {
+
+    private TestBottomScrollView mScrollView;
+    private NavigationBar mNavigationBar;
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        mScrollView = new TestBottomScrollView(getContext());
+        mNavigationBar = new NavigationBar(getContext());
+    }
+
+    @SmallTest
+    public void testRequireScroll() {
+        RequireScrollHelper.requireScroll(mNavigationBar, mScrollView);
+        assertEquals("More button should be gone initially", View.GONE,
+                mNavigationBar.getMoreButton().getVisibility());
+        assertEquals("Next button should be shown", View.VISIBLE,
+                mNavigationBar.getNextButton().getVisibility());
+
+        mScrollView.listener.onRequiresScroll();
+        assertEquals("More button should be shown when scroll is required", View.VISIBLE,
+                mNavigationBar.getMoreButton().getVisibility());
+        assertEquals("Next button should not be shown when scroll is required", View.GONE,
+                mNavigationBar.getNextButton().getVisibility());
+    }
+
+    @SmallTest
+    public void testScrolledToBottom() {
+        RequireScrollHelper.requireScroll(mNavigationBar, mScrollView);
+        mScrollView.listener.onRequiresScroll();
+        assertEquals("More button should be shown when scroll is required", View.VISIBLE,
+                mNavigationBar.getMoreButton().getVisibility());
+        assertEquals("Next button should not be shown when scroll is required", View.GONE,
+                mNavigationBar.getNextButton().getVisibility());
+
+        mScrollView.listener.onScrolledToBottom();
+        assertEquals("More button should be hidden when scrolled to bottom", View.GONE,
+                mNavigationBar.getMoreButton().getVisibility());
+        assertEquals("Next button should be shown when scrolled to bottom", View.VISIBLE,
+                mNavigationBar.getNextButton().getVisibility());
+    }
+
+    @SmallTest
+    public void testClickScrollButton() {
+        RequireScrollHelper.requireScroll(mNavigationBar, mScrollView);
+        assertEquals("ScrollView page should be initially 0", 0, mScrollView.page);
+        mScrollView.listener.onRequiresScroll();
+        mNavigationBar.getMoreButton().performClick();
+        assertEquals("ScrollView page should be scrolled by 1", 1, mScrollView.page);
+    }
+
+    private static class TestBottomScrollView extends BottomScrollView {
+
+        public BottomScrollListener listener;
+        public int page = 0;
+
+        public TestBottomScrollView(Context context) {
+            super(context);
+        }
+
+        @Override
+        public void setBottomScrollListener(BottomScrollListener listener) {
+            this.listener = listener;
+        }
+
+        @Override
+        public boolean pageScroll(int direction) {
+            if (direction == FOCUS_DOWN) {
+                page++;
+            } else if (direction == FOCUS_UP) {
+                page--;
+            }
+            return super.pageScroll(direction);
+        }
+    }
+}