Adding option for adding new tab in tab manager for chrome shell.

chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java

 // Copyright 2014 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.shell;
 
 import android.content.Context;
 import android.util.AttributeSet;
+import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.ViewParent;
 import android.widget.FrameLayout;
 import android.widget.LinearLayout;
 
 import org.chromium.chrome.browser.EmptyTabObserver;
 import org.chromium.chrome.browser.Tab;
 import org.chromium.chrome.browser.tabmodel.EmptyTabModelObserver;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
+import org.chromium.chrome.browser.widget.accessibility.AccessibilityTabModelWrapper;
 import org.chromium.content.browser.ContentVideoViewClient;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content.browser.ContentViewRenderView;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.ui.base.PageTransition;
 import org.chromium.ui.base.WindowAndroid;
 
 /**
  * The TabManager hooks together all of the related {@link View}s that are used to represent
  * a {@link ChromeShellTab}.  It properly builds a {@link ChromeShellTab} and makes sure that the
  * {@link ChromeShellToolbar} and {@link ContentViewRenderView} show the proper content.
  */
 public class TabManager extends LinearLayout {
     private static final String DEFAULT_URL = "http://www.google.com";
 
     private ViewGroup mContentViewHolder;
     private ContentViewRenderView mContentViewRenderView;
     private ChromeShellToolbar mToolbar;
 
     private ChromeShellTab mCurrentTab;
 
     private String mStartupUrl = DEFAULT_URL;
 
     private ChromeShellTabModelSelector mTabModelSelector;
+    private AccessibilityTabModelWrapper mTabModelWrapper;
 
     private final EmptyTabModelObserver mTabModelObserver = new EmptyTabModelObserver() {
         @Override
         public void didSelectTab(Tab tab, TabSelectionType type, int lastId) {
             assert tab instanceof ChromeShellTab;
             setCurrentTab((ChromeShellTab) tab);
-            mTabModelSelector.hideTabSwitcher();
+            hideTabSwitcher();
         }
 
         @Override
         public void willCloseTab(Tab tab, boolean animate) {
             if (tab == mCurrentTab) setCurrentTab(null);
         }
     };
 
     /**
      * @param context The Context the view is running in.
@@ skipping 13 matching lines @@
         assert videoViewClient != null;
 
         mContentViewHolder = (ViewGroup) findViewById(R.id.content_container);
 
         mTabModelSelector = new ChromeShellTabModelSelector(
                 window, videoViewClient, mContentViewHolder, this);
         mTabModelSelector.getModel(false).addObserver(mTabModelObserver);
 
         mToolbar = (ChromeShellToolbar) findViewById(R.id.toolbar);
         mToolbar.setTabManager(this);
+        mTabModelWrapper = mTabModelSelector.getTabModelWrapper();
         mContentViewRenderView = new ContentViewRenderView(getContext()) {
             @Override
             protected void onReadyToRender() {
                 if (mCurrentTab == null) createTab(mStartupUrl, TabLaunchType.FROM_RESTORE);
             }
         };
         mContentViewRenderView.onNativeLibraryLoaded(window);
         mContentViewHolder.addView(mContentViewRenderView,
                 new FrameLayout.LayoutParams(
                         FrameLayout.LayoutParams.MATCH_PARENT,
@@ skipping 83 matching lines @@
 
     private void setupContent() {
         View view = mCurrentTab.getView();
         ContentViewCore contentViewCore = mCurrentTab.getContentViewCore();
         mContentViewHolder.addView(view);
         mContentViewRenderView.setCurrentContentViewCore(contentViewCore);
         view.requestFocus();
         contentViewCore.onShow();
     }
 
+    /*
+     * Hide the tab switcher.
+     */
+    public void hideTabSwitcher() {
+        if (mTabModelWrapper == null) return;
+        mToolbar.showAddButton(false);

[Bernhard Bauer, 2014/11/10 13:58:33]

Is there some method to where these calls appear? I could see doing both at the
beginning of the method, both at the end, or even one at the beginning and one
at the end (making the methods inverse to each other), but this seems a bit...
random.

[divya.bansal, 2014/11/11 05:18:19]

Done.

+        ViewParent parent = mTabModelWrapper.getParent();
+        if (parent != null) {
+            assert parent == mContentViewHolder;
+            mContentViewHolder.removeView(mTabModelWrapper);
+        }
+    }
+
+    private void showTabSwitcher() {
+        if (mTabModelWrapper == null) {
+            mTabModelWrapper = (AccessibilityTabModelWrapper) LayoutInflater.from(
+                    mContentViewHolder.getContext()).inflate(
+                            R.layout.accessibility_tab_switcher, null);
+            mTabModelWrapper.setup(null);
+            mTabModelWrapper.setTabModelSelector(mTabModelSelector);
+        }
+
+        if (mTabModelWrapper.getParent() == null) {
+            mContentViewHolder.addView(mTabModelWrapper);
+        }
+        mToolbar.showAddButton(true);
+    }
+
+    public boolean isTabSwitcherVisible() {
+        return mTabModelWrapper != null && mTabModelWrapper.getParent() == mContentViewHolder;
+    }
+
     /**
      * Toggles the tab switcher visibility.
      */
     public void toggleTabSwitcher() {
-        mTabModelSelector.toggleTabSwitcher();
-    }
-
-    public boolean isTabSwitcherVisible() {
-        return mTabModelSelector.isTabSwitcherVisible();
-    }
-
-    public void hideTabSwitcher() {
-        mTabModelSelector.hideTabSwitcher();
+        if (!isTabSwitcherVisible()) {
+            showTabSwitcher();
+        } else {
+            hideTabSwitcher();
+        }
     }
 
     /**
      * Opens a URL in the current tab if one exists, or in a new tab otherwise.
      * @param url The URL to open.
      * @return The tab used to open the provided URL.
      */
     public Tab openUrl(String url) {
         LoadUrlParams loadUrlParams = new LoadUrlParams(url);
         loadUrlParams.setTransitionType(PageTransition.TYPED | PageTransition.FROM_ADDRESS_BAR);
         Tab tab = mTabModelSelector.getCurrentTab();
         if (tab != null) {
             tab.loadUrl(loadUrlParams);
             return tab;
         }
         return createTab(url, TabLaunchType.FROM_KEYBOARD);
     }
 }