[Home] Record some user actions for the Chrome Home BottomSheet

chrome/android/java/src/org/chromium/chrome/browser/widget/bottomsheet/BottomSheetContentController.java

 // Copyright 2017 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.
 
 package org.chromium.chrome.browser.widget.bottomsheet;
 
 import android.content.Context;
 import android.content.res.Resources;
+import android.support.annotation.IntDef;
 import android.support.design.internal.BottomNavigationItemView;
 import android.support.design.internal.BottomNavigationMenuView;
 import android.support.design.widget.BottomNavigationView;
 import android.support.design.widget.BottomNavigationView.OnNavigationItemSelectedListener;
 import android.util.AttributeSet;
 import android.view.MenuItem;
 import android.view.View;
 
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.bookmarks.BookmarkSheetContent;
 import org.chromium.chrome.browser.download.DownloadSheetContent;
 import org.chromium.chrome.browser.history.HistorySheetContent;
 import org.chromium.chrome.browser.suggestions.SuggestionsBottomSheetContent;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.util.MathUtils;
 import org.chromium.chrome.browser.widget.bottomsheet.BottomSheet.BottomSheetContent;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
 import java.util.Map.Entry;
 
 /**
  * Displays and controls a {@link BottomNavigationView} fixed to the bottom of the
  * {@link BottomSheet}. Also manages {@link BottomSheetContent} displayed in the BottomSheet.
  */
 public class BottomSheetContentController extends BottomNavigationView
-        implements BottomSheetObserver, OnNavigationItemSelectedListener {
+        implements OnNavigationItemSelectedListener {
+    /** The different types of content that may be displayed in the bottom sheet. */
+    @IntDef({TYPE_SUGGESTIONS, TYPE_DOWNLOADS, TYPE_BOOKMARKS, TYPE_HISTORY})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface ContentType {}
+    public static final int TYPE_SUGGESTIONS = 0;
+    public static final int TYPE_DOWNLOADS = 1;
+    public static final int TYPE_BOOKMARKS = 2;
+    public static final int TYPE_HISTORY = 3;
+
+    private final Map<Integer, BottomSheetContent> mBottomSheetContents = new HashMap<>();
+
+    private final BottomSheetObserver mBottomSheetObserver = new EmptyBottomSheetObserver() {
+        @Override
+        public void onTransitionPeekToHalf(float transitionFraction) {
+            float offsetY = (mBottomSheet.getMinOffset() - mBottomSheet.getSheetOffsetFromBottom())
+                    + mDistanceBelowToolbarPx;
+            setTranslationY((int) Math.max(offsetY, 0f));
+            setVisibility(
+                    MathUtils.areFloatsEqual(transitionFraction, 0f) ? View.GONE : View.VISIBLE);
+        }
+
+        @Override
+        public void onSheetOpened() {
+            if (!mDefaultContentInitialized && mTabModelSelector.getCurrentTab() != null) {
+                initializeDefaultContent();
+            }
+        }
+
+        @Override
+        public void onSheetClosed() {
+            Iterator<Entry<Integer, BottomSheetContent>> contentIterator =
+                    mBottomSheetContents.entrySet().iterator();
+            while (contentIterator.hasNext()) {
+                Entry<Integer, BottomSheetContent> entry = contentIterator.next();
+                if (entry.getKey() == R.id.action_home) continue;
+
+                entry.getValue().destroy();
+                contentIterator.remove();
+            }
+            // TODO(twellington): determine a policy for destroying the
+            //                    SuggestionsBottomSheetContent.
+
+            if (mSelectedItemId == 0 || mSelectedItemId == R.id.action_home) return;
+
+            showBottomSheetContent(R.id.action_home);
+        }
+    };
+
     private BottomSheet mBottomSheet;
     private TabModelSelector mTabModelSelector;
     private float mDistanceBelowToolbarPx;
     private int mSelectedItemId;
     private boolean mDefaultContentInitialized;
 
-    private final Map<Integer, BottomSheetContent> mBottomSheetContents = new HashMap<>();
-
     public BottomSheetContentController(Context context, AttributeSet atts) {
         super(context, atts);
     }
 
     /**
      * Initializes the {@link BottomSheetContentController}.
      * @param bottomSheet The {@link BottomSheet} associated with this bottom nav.
      * @param controlContainerHeight The height of the control container in px.
      * @param tabModelSelector The {@link TabModelSelector} for the application.
      */
     public void init(BottomSheet bottomSheet, int controlContainerHeight,
             TabModelSelector tabModelSelector) {
         mBottomSheet = bottomSheet;
-        mBottomSheet.addObserver(this);
+        mBottomSheet.addObserver(mBottomSheetObserver);
         mTabModelSelector = tabModelSelector;
 
         Resources res = getContext().getResources();
         mDistanceBelowToolbarPx = controlContainerHeight
                 + res.getDimensionPixelOffset(R.dimen.bottom_nav_space_from_toolbar);
 
         setOnNavigationItemSelectedListener(this);
         disableShiftingMode();
     }
 
     /**
      * Initialize the default {@link BottomSheetContent}.
      */
     public void initializeDefaultContent() {
         if (mDefaultContentInitialized) return;
         showBottomSheetContent(R.id.action_home);
         mDefaultContentInitialized = true;
     }
 
     @Override
     public boolean onNavigationItemSelected(MenuItem item) {
         if (mSelectedItemId == item.getItemId()) return false;
 
         showBottomSheetContent(item.getItemId());
         return true;
     }
 
-    @Override
-    public void onTransitionPeekToHalf(float transitionFraction) {
-        float offsetY = (mBottomSheet.getMinOffset() - mBottomSheet.getSheetOffsetFromBottom())
-                + mDistanceBelowToolbarPx;
-        setTranslationY((int) Math.max(offsetY, 0f));
-        setVisibility(MathUtils.areFloatsEqual(transitionFraction, 0f) ? View.GONE : View.VISIBLE);
-    }
-
-    @Override
-    public void onSheetOpened() {
-        if (!mDefaultContentInitialized && mTabModelSelector.getCurrentTab() != null) {
-            initializeDefaultContent();
-        }
-    }
-
-    @Override
-    public void onSheetClosed() {
-        Iterator<Entry<Integer, BottomSheetContent>> contentIterator =
-                mBottomSheetContents.entrySet().iterator();
-        while (contentIterator.hasNext()) {
-            Entry<Integer, BottomSheetContent> entry = contentIterator.next();
-            if (entry.getKey() == R.id.action_home) continue;
-
-            entry.getValue().destroy();
-            contentIterator.remove();
-        }
-        // TODO(twellington): determine a policy for destroying the SuggestionsBottomSheetContent.
-
-        if (mSelectedItemId == 0 || mSelectedItemId == R.id.action_home) return;
-
-        showBottomSheetContent(R.id.action_home);
-    }
-
-    @Override
-    public void onLoadUrl(String url) {}
-
-    @Override
-    public void onSheetOffsetChanged(float heightFraction) {}
-
     // TODO(twellington): remove this once the support library is updated to allow disabling
     //                    shifting mode or determines shifting mode based on the width of the
     //                    child views.
     private void disableShiftingMode() {
         BottomNavigationMenuView menuView = (BottomNavigationMenuView) getChildAt(0);
         try {
             Field shiftingMode = menuView.getClass().getDeclaredField("mShiftingMode");
             shiftingMode.setAccessible(true);
             shiftingMode.setBoolean(menuView, false);
             shiftingMode.setAccessible(false);
@@ skipping 32 matching lines @@
         // There are some bugs related to programatically selecting menu items that are fixed in
         // newer support library versions.
         // TODO(twellington): remove this after the support library is rolled.
         if (mSelectedItemId != 0) getMenu().findItem(mSelectedItemId).setChecked(false);
         mSelectedItemId = navItemId;
         getMenu().findItem(mSelectedItemId).setChecked(true);
 
         mBottomSheet.showContent(getSheetContentForId(mSelectedItemId));
     }
 }