Implement lazy initialization for VrShellDelegate

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java

 // Copyright 2015 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;
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.SearchManager;
@@ skipping 113 matching lines @@
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorTabObserver;
 import org.chromium.chrome.browser.tabmodel.TabModelUtils;
 import org.chromium.chrome.browser.tabmodel.TabWindowManager;
 import org.chromium.chrome.browser.toolbar.Toolbar;
 import org.chromium.chrome.browser.toolbar.ToolbarControlContainer;
 import org.chromium.chrome.browser.toolbar.ToolbarManager;
 import org.chromium.chrome.browser.util.ChromeFileProvider;
 import org.chromium.chrome.browser.util.ColorUtils;
 import org.chromium.chrome.browser.util.FeatureUtilities;
+import org.chromium.chrome.browser.vr_shell.VrShellDelegate;
 import org.chromium.chrome.browser.webapps.AddToHomescreenManager;
 import org.chromium.chrome.browser.widget.BottomSheet;
 import org.chromium.chrome.browser.widget.ControlContainer;
 import org.chromium.chrome.browser.widget.EmptyBottomSheetObserver;
 import org.chromium.chrome.browser.widget.FadingBackgroundView;
 import org.chromium.components.bookmarks.BookmarkId;
 import org.chromium.content.browser.ContentVideoView;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content.common.ContentSwitches;
 import org.chromium.content_public.browser.ContentBitmapCallback;
@@ skipping 668 matching lines @@
                 MultiWindowUtils.getInstance().isInMultiWindowMode(this));
     }
 
     @Override
     public void onPauseWithNative() {
         RecordUserAction.record("MobileGoToBackground");
         Tab tab = getActivityTab();
         if (tab != null) {
             getTabContentManager().cacheTabThumbnail(tab);
         }
+        VrShellDelegate.maybePauseVR(this);
         markSessionEnd();
         super.onPauseWithNative();
     }
 
     @Override
     public void onStopWithNative() {
         Tab tab = getActivityTab();
         if (tab != null && !hasWindowFocus()) tab.onActivityHidden();
         if (mAppMenuHandler != null) mAppMenuHandler.hideAppMenu();
 
@@ skipping 310 matching lines @@
         mRemoveWindowBackgroundDone = true;
     }
 
     @Override
     public void finishNativeInitialization() {
         mNativeInitialized = true;
         maybeRemoveWindowBackground();
         DownloadManagerService.getDownloadManagerService(
                 getApplicationContext()).onActivityLaunched();
 
+        VrShellDelegate.onNativeLibraryAvailable();
         super.finishNativeInitialization();
     }
 
     /**
      * Called when the accessibility status of this device changes.  This might be triggered by
      * touch exploration or general accessibility status updates.  It is an aggregate of two other
      * accessibility update methods.
      * @see #onAccessibilityModeChanged(boolean)
      * @see #onTouchExplorationStateChanged(boolean)
      * @param enabled Whether or not accessibility and touch exploration are currently enabled.
@@ skipping 509 matching lines @@
         if (isInMultiWindowMode) {
             RecordUserAction.record("Android.MultiWindowMode.Enter");
         } else {
             RecordUserAction.record("Android.MultiWindowMode.Exit");
         }
     }
 
     @Override
     public final void onBackPressed() {
         RecordUserAction.record("SystemBack");
+        if (VrShellDelegate.onBackPressed()) return;
         if (mCompositorViewHolder != null) {
             LayoutManager layoutManager = mCompositorViewHolder.getLayoutManager();
             if (layoutManager != null && layoutManager.onBackPressed()) return;
         }
 
         ContentViewCore contentViewCore = getContentViewCore();
         if (contentViewCore != null && contentViewCore.isSelectActionBarShowing()) {
             contentViewCore.clearSelection();
             return;
         }
@@ skipping 390 matching lines @@
         RecordHistogram.recordBooleanHistogram(
                 "Android.MultiWindowMode.IsTabletScreenWidthBelow600",
                 mScreenWidthDp < DeviceFormFactor.MINIMUM_TABLET_WIDTH_DP);
 
         if (mScreenWidthDp < DeviceFormFactor.MINIMUM_TABLET_WIDTH_DP) {
             RecordHistogram.recordLinearCountHistogram(
                     "Android.MultiWindowMode.TabletScreenWidth", mScreenWidthDp, 1,
                     DeviceFormFactor.MINIMUM_TABLET_WIDTH_DP, 50);
         }
     }
+
+    /**
+     * Called when VR mode is entered using this activity. 2D UI components that steal focus or
+     * draw over VR contents should be hidden in this call.
+     */
+    public void onEnterVR() {}
+
+    /**
+     * Called when VR mode using this activity is exited. Any state set for VR should be restored
+     * in this call, including showing 2D UI that was hidden.
+     */
+    public void onExitVR() {}
 }