Introducing the split action bar.

Apply (or extend) the theme Theme.Holo.SplitActionBarWhenNarrow or
Theme.Holo.Light.SplitActionBarWhenNarrow to enable splitting the
action bar across both the top and bottom of the screen. This places
the action menu along the bottom, leaving more room at the top for
titles, navigation, and custom views and more room at the bottom for
menu items.

TODO: Refine layout of the action menu when placed at the bottom of
the screen. Make action modes split as well.

Change-Id: I92c91f99c533f26aecf6b828ed041386c4f16922

13 files changed, 114 insertions, 20 deletions

diff --git a/api/current.txt b/api/current.txt
index 5aa840d..a98ffae 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -1490,9 +1490,11 @@ package android {
     field public static final int Theme_Holo_Light_Dialog_NoActionBar_MinWidth = 16973942; // 0x1030076
     field public static final int Theme_Holo_Light_NoActionBar = 16974064; // 0x10300f0
     field public static final int Theme_Holo_Light_Panel = 16973948; // 0x103007c
+    field public static final int Theme_Holo_Light_SplitActionBarWhenNarrow = 16974067; // 0x10300f3
     field public static final int Theme_Holo_NoActionBar = 16973932; // 0x103006c
     field public static final int Theme_Holo_NoActionBar_Fullscreen = 16973933; // 0x103006d
     field public static final int Theme_Holo_Panel = 16973947; // 0x103007b
+    field public static final int Theme_Holo_SplitActionBarWhenNarrow = 16974066; // 0x10300f2
     field public static final int Theme_Holo_Wallpaper = 16973949; // 0x103007d
     field public static final int Theme_Holo_Wallpaper_NoTitleBar = 16973950; // 0x103007e
     field public static final int Theme_InputMethod = 16973908; // 0x1030054
diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index f5849c2..02b6619 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -2482,6 +2482,7 @@ public class Activity extends ContextThemeWrapper
                 break;
 
             case Window.FEATURE_ACTION_BAR:
+                initActionBar();
                 mActionBar.dispatchMenuVisibilityChanged(false);
                 break;
         }
diff --git a/core/java/com/android/internal/app/ActionBarImpl.java b/core/java/com/android/internal/app/ActionBarImpl.java
index dccfa6c..57df259 100644
--- a/core/java/com/android/internal/app/ActionBarImpl.java
+++ b/core/java/com/android/internal/app/ActionBarImpl.java
@@ -71,7 +71,7 @@ public class ActionBarImpl extends ActionBar {
     private ActionBarContainer mContainerView;
     private ActionBarView mActionView;
     private ActionBarContextView mUpperContextView;
-    private LinearLayout mLowerContextView;
+    private LinearLayout mLowerView;
     private View mContentView;
     private ViewGroup mExternalTabView;
 
@@ -106,8 +106,8 @@ public class ActionBarImpl extends ActionBar {
             new AnimatorListenerAdapter() { // NORMAL_VIEW
                 @Override
                 public void onAnimationEnd(Animator animation) {
-                    if (mLowerContextView != null) {
-                        mLowerContextView.removeAllViews();
+                    if (mLowerView != null) {
+                        mLowerView.removeAllViews();
                     }
                     mCurrentModeAnim = null;
                     hideAllExcept(NORMAL_VIEW);
@@ -162,7 +162,7 @@ public class ActionBarImpl extends ActionBar {
         mActionView = (ActionBarView) decor.findViewById(com.android.internal.R.id.action_bar);
         mUpperContextView = (ActionBarContextView) decor.findViewById(
                 com.android.internal.R.id.action_context_bar);
-        mLowerContextView = (LinearLayout) decor.findViewById(
+        mLowerView = (LinearLayout) decor.findViewById(
                 com.android.internal.R.id.lower_action_context_bar);
         mContainerView = (ActionBarContainer) decor.findViewById(
                 com.android.internal.R.id.action_bar_container);
@@ -173,8 +173,8 @@ public class ActionBarImpl extends ActionBar {
         }
 
         mActionView.setContextView(mUpperContextView);
-        mContextDisplayMode = mLowerContextView == null ?
-                CONTEXT_DISPLAY_NORMAL : CONTEXT_DISPLAY_SPLIT;
+        mContextDisplayMode = mActionView.isSplitActionBar() ?
+                CONTEXT_DISPLAY_SPLIT : CONTEXT_DISPLAY_NORMAL;
 
         if (!mActionView.hasEmbeddedTabs()) {
             HorizontalScrollView tabScroller = new HorizontalScrollView(mContext);
@@ -348,9 +348,9 @@ public class ActionBarImpl extends ActionBar {
             mode.invalidate();
             mUpperContextView.initForMode(mode);
             animateTo(CONTEXT_VIEW);
-            if (mLowerContextView != null) {
+            if (mLowerView != null) {
                 // TODO animate this
-                mLowerContextView.setVisibility(View.VISIBLE);
+                mLowerView.setVisibility(View.VISIBLE);
             }
             mActionMode = mode;
             return mode;
@@ -616,9 +616,9 @@ public class ActionBarImpl extends ActionBar {
 
             // Clear out the context mode views after the animation finishes
             mUpperContextView.closeMode();
-            if (mLowerContextView != null && mLowerContextView.getVisibility() != View.GONE) {
+            if (mLowerView != null && mLowerView.getVisibility() != View.GONE) {
                 // TODO Animate this
-                mLowerContextView.setVisibility(View.GONE);
+                mLowerView.setVisibility(View.GONE);
             }
             mActionMode = null;
 
diff --git a/core/java/com/android/internal/view/menu/ActionMenuPresenter.java b/core/java/com/android/internal/view/menu/ActionMenuPresenter.java
index a05fa53..e210b78 100644
--- a/core/java/com/android/internal/view/menu/ActionMenuPresenter.java
+++ b/core/java/com/android/internal/view/menu/ActionMenuPresenter.java
@@ -73,10 +73,11 @@ public class ActionMenuPresenter extends BaseMenuPresenter {
 
         int width = mWidthLimit;
         if (mReserveOverflow) {
-            OverflowMenuButton button = new OverflowMenuButton(mContext);
-            mOverflowButton = button;
-            final int spec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
-            mOverflowButton.measure(spec, spec);
+            if (mOverflowButton == null) {
+                mOverflowButton = new OverflowMenuButton(mContext);
+                final int spec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
+                mOverflowButton.measure(spec, spec);
+            }
             width -= mOverflowButton.getMeasuredWidth();
         } else {
             mOverflowButton = null;
@@ -88,6 +89,17 @@ public class ActionMenuPresenter extends BaseMenuPresenter {
         mScrapActionButtonView = null;
     }
 
+    public void setWidthLimit(int width) {
+        if (mReserveOverflow) {
+            width -= mOverflowButton.getMeasuredWidth();
+        }
+        mActionItemWidthLimit = width;
+    }
+
+    public void setItemLimit(int itemCount) {
+        mMaxItems = itemCount;
+    }
+
     @Override
     public MenuView getMenuView(ViewGroup root) {
         MenuView result = super.getMenuView(root);
diff --git a/core/java/com/android/internal/widget/ActionBarView.java b/core/java/com/android/internal/widget/ActionBarView.java
index a572e11..0c13f7b 100644
--- a/core/java/com/android/internal/widget/ActionBarView.java
+++ b/core/java/com/android/internal/widget/ActionBarView.java
@@ -110,7 +110,7 @@ public class ActionBarView extends ViewGroup {
     private int mProgressStyle;
     private int mIndeterminateProgressStyle;
 
-    private boolean mShowMenu;
+    private boolean mSplitActionBar;
     private boolean mUserTitle;
     private boolean mIncludeTabs;
 
@@ -119,6 +119,7 @@ public class ActionBarView extends ViewGroup {
     private ActionMenuPresenter mActionMenuPresenter;
     
     private ActionBarContextView mContextView;
+    private ViewGroup mSplitView;
 
     private ActionMenuItem mLogoNavItem;
 
@@ -245,6 +246,26 @@ public class ActionBarView extends ViewGroup {
         addView(mIndeterminateProgressView);
     }
 
+    public void setSplitActionBar(boolean splitActionBar) {
+        if (mSplitActionBar != splitActionBar) {
+            if (mMenuView != null) {
+                if (splitActionBar) {
+                    removeView(mMenuView);
+                    if (mSplitView != null) {
+                        mSplitView.addView(mMenuView);
+                    }
+                } else {
+                    addView(mMenuView);
+                }
+            }
+            mSplitActionBar = splitActionBar;
+        }
+    }
+
+    public boolean isSplitActionBar() {
+        return mSplitActionBar;
+    }
+
     public boolean hasEmbeddedTabs() {
         return mIncludeTabs;
     }
@@ -284,10 +305,29 @@ public class ActionBarView extends ViewGroup {
         final LayoutParams layoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT,
                 LayoutParams.MATCH_PARENT);
         menuView.setLayoutParams(layoutParams);
-        addView(menuView);
+        if (!mSplitActionBar) {
+            addView(menuView);
+        } else {
+            // Allow full screen width in split mode.
+            mActionMenuPresenter.setWidthLimit(
+                    getContext().getResources().getDisplayMetrics().widthPixels);
+            // No limit to the item count; use whatever will fit.
+            mActionMenuPresenter.setItemLimit(Integer.MAX_VALUE);
+            if (mSplitView != null) {
+                mSplitView.addView(menuView);
+            } // We'll add this later if we missed it this time.
+        }
         mMenuView = menuView;
     }
 
+    public void setSplitView(ViewGroup splitView) {
+        mSplitView = splitView;
+        splitView.setVisibility(VISIBLE);
+        if (mMenuView != null) {
+            splitView.addView(mMenuView);
+        }
+    }
+
     public boolean showOverflowMenu() {
         if (mActionMenuPresenter != null) {
             return mActionMenuPresenter.showOverflowMenu();
@@ -718,7 +758,7 @@ public class ActionBarView extends ViewGroup {
             leftOfCenter -= homeWidth;
         }
         
-        if (mMenuView != null) {
+        if (mMenuView != null && mMenuView.getParent() == this) {
             availableWidth = measureChildView(mMenuView, availableWidth,
                     childSpecHeight, 0);
             rightOfCenter -= mMenuView.getMeasuredWidth();
@@ -880,7 +920,7 @@ public class ActionBarView extends ViewGroup {
         }
 
         int menuLeft = r - l - getPaddingRight();
-        if (mMenuView != null) {
+        if (mMenuView != null && mMenuView.getParent() == this) {
             positionChildInverse(mMenuView, menuLeft, y, contentHeight);
             menuLeft -= mMenuView.getMeasuredWidth();
         }
diff --git a/core/res/res/layout/screen_action_bar.xml b/core/res/res/layout/screen_action_bar.xml
index 70af265..14af446 100644
--- a/core/res/res/layout/screen_action_bar.xml
+++ b/core/res/res/layout/screen_action_bar.xml
@@ -47,5 +47,6 @@ This is an optimized layout for a screen with the Action Bar enabled.
                   android:layout_width="match_parent"
                   android:layout_height="wrap_content"
                   style="?android:attr/actionBarStyle"
-                  android:visibility="gone" />
+                  android:visibility="gone"
+                  android:gravity="center"/>
 </LinearLayout>
diff --git a/core/res/res/layout/screen_action_bar_overlay.xml b/core/res/res/layout/screen_action_bar_overlay.xml
index cfa335e..aebbe41 100644
--- a/core/res/res/layout/screen_action_bar_overlay.xml
+++ b/core/res/res/layout/screen_action_bar_overlay.xml
@@ -51,5 +51,6 @@ the Action Bar enabled overlaying application content.
                   android:layout_height="wrap_content"
                   android:layout_alignParentBottom="true"
                   style="?android:attr/actionBarStyle"
-                  android:visibility="gone" />
+                  android:visibility="gone"
+                  android:gravity="center"/>
 </RelativeLayout>
diff --git a/core/res/res/values-w480dp/bools.xml b/core/res/res/values-w480dp/bools.xml
index c202d90..8206e79 100644
--- a/core/res/res/values-w480dp/bools.xml
+++ b/core/res/res/values-w480dp/bools.xml
@@ -19,4 +19,5 @@
 <resources>
     <bool name="allow_action_menu_item_text_with_icon">true</bool>
     <bool name="action_bar_embed_tabs">true</bool>
+    <bool name="split_action_bar_is_narrow">false</bool>
 </resources>
diff --git a/core/res/res/values/attrs.xml b/core/res/res/values/attrs.xml
index 3a44e4f..dac3bd2 100755
--- a/core/res/res/values/attrs.xml
+++ b/core/res/res/values/attrs.xml
@@ -299,6 +299,10 @@
              when there is not reserved space for their UI (such as an Action Bar). -->
         <attr name="windowActionModeOverlay" format="boolean" />
 
+        <!-- Flag indicating that the action bar should be split to provide more
+             room for elements. -->
+        <attr name="windowSplitActionBar" format="boolean" />
+
         <!-- Defines the default soft input state that this window would
              like when it is displayed. -->
         <attr name="windowSoftInputMode">
@@ -1429,6 +1433,7 @@
         <attr name="windowActionBar" />
         <attr name="windowActionModeOverlay" />
         <attr name="windowActionBarOverlay" />
+        <attr name="windowSplitActionBar" />
         <attr name="windowEnableSplitTouch" />
         <attr name="windowCloseOnTouchOutside" />
         <!-- The minimum width the window is allowed to be, along the major
diff --git a/core/res/res/values/bools.xml b/core/res/res/values/bools.xml
index 6eb006f..8e27be4 100644
--- a/core/res/res/values/bools.xml
+++ b/core/res/res/values/bools.xml
@@ -19,4 +19,5 @@
 <resources>
     <bool name="allow_action_menu_item_text_with_icon">false</bool>
     <bool name="action_bar_embed_tabs">false</bool>
+    <bool name="split_action_bar_is_narrow">true</bool>
 </resources>
diff --git a/core/res/res/values/public.xml b/core/res/res/values/public.xml
index 501d478..7ca5e98 100644
--- a/core/res/res/values/public.xml
+++ b/core/res/res/values/public.xml
@@ -1660,6 +1660,8 @@
 
   <public type="style" name="Theme.Holo.Light.NoActionBar" />
   <public type="style" name="TextAppearance.SuggestionHighlight" />
+  <public type="style" name="Theme.Holo.SplitActionBarWhenNarrow" />
+  <public type="style" name="Theme.Holo.Light.SplitActionBarWhenNarrow" />
 
   <public type="attr" name="textSuggestionsWindowStyle" />
   <public type="attr" name="textEditSuggestionsBottomWindowLayout" />
diff --git a/core/res/res/values/themes.xml b/core/res/res/values/themes.xml
index be7b42f..cdfdd11 100644
--- a/core/res/res/values/themes.xml
+++ b/core/res/res/values/themes.xml
@@ -1538,4 +1538,17 @@
         <item name="android:windowNoTitle">true</item>
     </style>
 
+    <!-- Variant of the holographic (dark) theme with an action bar that
+         splits across the top and bottom of the activity when constrained
+         for horizontal space. -->
+    <style name="Theme.Holo.SplitActionBarWhenNarrow">
+        <item name="android:windowSplitActionBar">@android:bool/split_action_bar_is_narrow</item>
+    </style>
+
+    <!-- Variant of the holographic (light) theme with an action bar that
+         splits across the top and bottom of the activity when constrained
+         for horizontal space. -->
+    <style name="Theme.Holo.Light.SplitActionBarWhenNarrow">
+        <item name="android:windowSplitActionBar">@android:bool/split_action_bar_is_narrow</item>
+    </style>
 </resources>
diff --git a/policy/src/com/android/internal/policy/impl/PhoneWindow.java b/policy/src/com/android/internal/policy/impl/PhoneWindow.java
index 73003c8..27b7e1c 100644
--- a/policy/src/com/android/internal/policy/impl/PhoneWindow.java
+++ b/policy/src/com/android/internal/policy/impl/PhoneWindow.java
@@ -2587,6 +2587,21 @@ public class PhoneWindow extends Window implements MenuBuilder.Callback {
                     if ((localFeatures & (1 << FEATURE_INDETERMINATE_PROGRESS)) != 0) {
                         mActionBar.initIndeterminateProgress();
                     }
+
+                    final boolean splitActionBar = getWindowStyle().getBoolean(
+                            com.android.internal.R.styleable.Window_windowSplitActionBar, false);
+                    if (splitActionBar) {
+                        final ViewGroup splitView = (ViewGroup) findViewById(
+                                com.android.internal.R.id.lower_action_context_bar);
+                        if (splitView != null) {
+                            mActionBar.setSplitActionBar(splitActionBar);
+                            mActionBar.setSplitView(splitView);
+                        } else {
+                            Log.e(TAG, "Window style requested split action bar with " +
+                                    "incompatible window decor! Ignoring request.");
+                        }
+                    }
+
                     // Post the panel invalidate for later; avoid application onCreateOptionsMenu
                     // being called in the middle of onCreate or similar.
                     mDecor.post(new Runnable() {