Bug 1016613 - Replace RemoteTabsPanel view with ViewStub in tabs_panel.xml and created new layout file to inflate the ViewStub when user clicks on 3rd button in TabsPanel. r=mcomella

This was done in order to save on resources and not create the RemoteTabsPanel until needed

mobile/android/base/resources/layout-large-land-v11/tabs_panel.xml

@@ -46,11 +46,10 @@
                 android:layout_height="match_parent"
                 android:visibility="gone"/>
 
-        <org.mozilla.gecko.tabs.RemoteTabsPanel
-                android:id="@+id/remote_tabs"
-                android:layout_height="match_parent"
-                android:layout_width="match_parent"
-                android:visibility="gone"/>
+        <ViewStub android:id="@+id/remote_tabs_panel_stub"
+                  android:layout="@layout/remote_tabs_panel_view"
+                  android:layout_width="match_parent"
+                  android:layout_height="match_parent"/>
 
     </view>
 

mobile/android/base/resources/layout/remote_tabs_panel_view.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<org.mozilla.gecko.tabspanel.RemoteTabsPanel xmlns:android="http://schemas.android.com/apk/res/android"
+                                             android:id="@+id/remote_tabs_panel"
+                                             android:layout_width="match_parent"
+                                             android:layout_height="match_parent"/>

mobile/android/base/resources/layout/tabs_panel.xml

@@ -45,11 +45,10 @@
                 android:layout_height="match_parent"
                 android:visibility="gone"/>
 
-        <org.mozilla.gecko.tabs.RemoteTabsPanel
-                android:id="@+id/remote_tabs"
-                android:layout_height="match_parent"
-                android:layout_width="match_parent"
-                android:visibility="gone"/>
+        <ViewStub android:id="@+id/remote_tabs_panel_stub"
+                  android:layout="@layout/remote_tabs_panel_view"
+                  android:layout_width="match_parent"
+                  android:layout_height="match_parent"/>
 
     </view>
 

mobile/android/base/tabs/TabsPanel.java

@@ -32,6 +32,7 @@ import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
+import android.view.ViewStub;
 import android.widget.Button;
 import android.widget.FrameLayout;
 import android.widget.ImageButton;
@@ -113,7 +114,7 @@ public class TabsPanel extends LinearLayout
             public void onResume() {
                 if (mPanel == mPanelRemote) {
                     // Refresh the remote panel.
-                    mPanelRemote.show();
+                    getRemotePanelView().show();
                 }
             }
 
@@ -127,7 +128,23 @@ public class TabsPanel extends LinearLayout
         };
     }
 
+    /**
+     * Initializes views in tabs_panel layout
+     *
+     * @throws IllegalStateException
+     *             mCurrentPanel must have a non-null value
+     */
     private void initialize() {
+        if (mCurrentPanel == null) {
+            throw new IllegalStateException(
+                    "mCurrentPanel cannot be null in order for RemotePanelView to be initialized");
+        }
+
+        if (mCurrentPanel == Panel.REMOTE_TABS) {
+            // Initializes mPanelRemote
+            getRemotePanelView();
+        }
+
         mHeader = (RelativeLayout) findViewById(R.id.tabs_panel_header);
         mTabsContainer = (TabsListContainer) findViewById(R.id.tabs_container);
 
@@ -137,9 +154,6 @@ public class TabsPanel extends LinearLayout
         mPanelPrivate = (PanelView) findViewById(R.id.private_tabs_panel);
         mPanelPrivate.setTabsPanel(this);
 
-        mPanelRemote = (PanelView) findViewById(R.id.remote_tabs);
-        mPanelRemote.setTabsPanel(this);
-
         mFooter = (RelativeLayout) findViewById(R.id.tabs_panel_footer);
 
         mAddTab = (ImageButton) findViewById(R.id.add_tab);
@@ -416,7 +430,7 @@ public class TabsPanel extends LinearLayout
                 mPanel = mPanelPrivate;
                 break;
             case REMOTE_TABS:
-                mPanel = mPanelRemote;
+                mPanel = getRemotePanelView();
                 break;
 
             default:
@@ -472,6 +486,9 @@ public class TabsPanel extends LinearLayout
     public void refresh() {
         removeAllViews();
 
+        // The View that mPanelRemote points to is invalidated because the layout is invalidated.
+        // mPanelRemote must be null in order to properly initialize RemotePanelView.
+        mPanelRemote = null;
         LayoutInflater.from(mContext).inflate(R.layout.tabs_panel, this);
         initialize();
 
@@ -570,4 +587,18 @@ public class TabsPanel extends LinearLayout
     public void setIconDrawable(Panel panel, int resource) {
         mTabWidget.setIconDrawable(panel.ordinal(), resource);
     }
+
+    /**
+     * Initializes mPanelRemote if necessary and provides getter because you
+     * should probably not access mPanelRemote directly
+     *
+     * @return PanelView
+     */
+    private PanelView getRemotePanelView() {
+        if (mPanelRemote == null) {
+            mPanelRemote = (PanelView) ((ViewStub) findViewById(R.id.remote_tabs_panel_stub)).inflate();
+            mPanelRemote.setTabsPanel(TabsPanel.this);
+        }
+        return mPanelRemote;
+    }
 }