Fix bug 5122319 - When action bar tabs run out of space they should

collapse in to a spinner.

When tabs are not given the option of dropping to their own row,
collapse them into a spinner when they would measure too large to be
visible all at once.

Fix bug 5095167 - zombie tabs return when they shouldn't when activity
handles its own orientation changes

Change-Id: I074419d99a22aa5dd1cbc00a66e600ec5cb0b54a

4 files changed, 235 insertions, 64 deletions

diff --git a/core/java/com/android/internal/app/ActionBarImpl.java b/core/java/com/android/internal/app/ActionBarImpl.java
index 008f400..0df7bcc 100644
--- a/core/java/com/android/internal/app/ActionBarImpl.java
+++ b/core/java/com/android/internal/app/ActionBarImpl.java
@@ -156,8 +156,6 @@ public class ActionBarImpl extends ActionBar {
                     "with a compatible window decor layout");
         }
 
-        mHasEmbeddedTabs = mContext.getResources().getBoolean(
-                com.android.internal.R.bool.action_bar_embed_tabs);
         mActionView.setContextView(mContextView);
         mContextDisplayMode = mActionView.isSplitActionBar() ?
                 CONTEXT_DISPLAY_SPLIT : CONTEXT_DISPLAY_NORMAL;
@@ -166,25 +164,31 @@ public class ActionBarImpl extends ActionBar {
         // Newer apps need to enable it explicitly.
         setHomeButtonEnabled(mContext.getApplicationInfo().targetSdkVersion <
                 Build.VERSION_CODES.ICE_CREAM_SANDWICH);
+
+        setHasEmbeddedTabs(mContext.getResources().getBoolean(
+                com.android.internal.R.bool.action_bar_embed_tabs));
     }
 
     public void onConfigurationChanged(Configuration newConfig) {
-        mHasEmbeddedTabs = mContext.getResources().getBoolean(
-                com.android.internal.R.bool.action_bar_embed_tabs);
+        setHasEmbeddedTabs(mContext.getResources().getBoolean(
+                com.android.internal.R.bool.action_bar_embed_tabs));
+    }
 
+    private void setHasEmbeddedTabs(boolean hasEmbeddedTabs) {
+        mHasEmbeddedTabs = hasEmbeddedTabs;
         // Switch tab layout configuration if needed
         if (!mHasEmbeddedTabs) {
             mActionView.setEmbeddedTabView(null);
             mContainerView.setTabContainer(mTabScrollView);
         } else {
             mContainerView.setTabContainer(null);
-            if (mTabScrollView != null) {
-                mTabScrollView.setVisibility(View.VISIBLE);
-            }
             mActionView.setEmbeddedTabView(mTabScrollView);
         }
-        mActionView.setCollapsable(!mHasEmbeddedTabs &&
-                getNavigationMode() == NAVIGATION_MODE_TABS);
+        final boolean isInTabMode = getNavigationMode() == NAVIGATION_MODE_TABS;
+        if (mTabScrollView != null) {
+            mTabScrollView.setVisibility(isInTabMode ? View.VISIBLE : View.GONE);
+        }
+        mActionView.setCollapsable(!mHasEmbeddedTabs && isInTabMode);
     }
 
     private void ensureTabsExist() {
@@ -192,7 +196,7 @@ public class ActionBarImpl extends ActionBar {
             return;
         }
 
-        ScrollingTabContainerView tabScroller = mActionView.createTabContainer();
+        ScrollingTabContainerView tabScroller = new ScrollingTabContainerView(mContext);
 
         if (mHasEmbeddedTabs) {
             tabScroller.setVisibility(View.VISIBLE);
@@ -925,18 +929,14 @@ public class ActionBarImpl extends ActionBar {
             case NAVIGATION_MODE_TABS:
                 mSavedTabPosition = getSelectedNavigationIndex();
                 selectTab(null);
-                if (!mActionView.hasEmbeddedTabs()) {
-                    mTabScrollView.setVisibility(View.GONE);
-                }
+                mTabScrollView.setVisibility(View.GONE);
                 break;
         }
         mActionView.setNavigationMode(mode);
         switch (mode) {
             case NAVIGATION_MODE_TABS:
                 ensureTabsExist();
-                if (!mActionView.hasEmbeddedTabs()) {
-                    mTabScrollView.setVisibility(View.VISIBLE);
-                }
+                mTabScrollView.setVisibility(View.VISIBLE);
                 if (mSavedTabPosition != INVALID_POSITION) {
                     setSelectedNavigationItem(mSavedTabPosition);
                     mSavedTabPosition = INVALID_POSITION;
diff --git a/core/java/com/android/internal/widget/ActionBarContainer.java b/core/java/com/android/internal/widget/ActionBarContainer.java
index a2d492b..b4d2d72 100644
--- a/core/java/com/android/internal/widget/ActionBarContainer.java
+++ b/core/java/com/android/internal/widget/ActionBarContainer.java
@@ -102,7 +102,7 @@ public class ActionBarContainer extends FrameLayout {
         return true;
     }
 
-    public void setTabContainer(View tabView) {
+    public void setTabContainer(ScrollingTabContainerView tabView) {
         if (mTabContainer != null) {
             removeView(mTabContainer);
         }
@@ -110,6 +110,7 @@ public class ActionBarContainer extends FrameLayout {
         if (tabView != null) {
             addView(tabView);
             tabView.getLayoutParams().width = LayoutParams.MATCH_PARENT;
+            tabView.setAllowCollapse(false);
         }
     }
 
diff --git a/core/java/com/android/internal/widget/ActionBarView.java b/core/java/com/android/internal/widget/ActionBarView.java
index 61df5c7..181958c 100644
--- a/core/java/com/android/internal/widget/ActionBarView.java
+++ b/core/java/com/android/internal/widget/ActionBarView.java
@@ -332,7 +332,10 @@ public class ActionBarView extends AbsActionBarView {
         mIncludeTabs = tabs != null;
         if (mIncludeTabs && mNavigationMode == ActionBar.NAVIGATION_MODE_TABS) {
             addView(mTabScrollView);
-            mTabScrollView.getLayoutParams().width = LayoutParams.WRAP_CONTENT;
+            ViewGroup.LayoutParams lp = mTabScrollView.getLayoutParams();
+            lp.width = LayoutParams.WRAP_CONTENT;
+            lp.height = LayoutParams.MATCH_PARENT;
+            tabs.setAllowCollapse(true);
         }
     }
 
@@ -649,18 +652,6 @@ public class ActionBarView extends AbsActionBarView {
         }
     }
 
-    public ScrollingTabContainerView createTabContainer() {
-        final LinearLayout tabLayout = new LinearLayout(getContext(), null,
-                com.android.internal.R.attr.actionBarTabBarStyle);
-        tabLayout.setMeasureWithLargestChildEnabled(true);
-        tabLayout.setLayoutParams(new LinearLayout.LayoutParams(
-                LinearLayout.LayoutParams.WRAP_CONTENT, mContentHeight));
-
-        final ScrollingTabContainerView scroller = new ScrollingTabContainerView(mContext);
-        scroller.setTabLayout(tabLayout);
-        return scroller;
-    }
-
     public void setDropdownAdapter(SpinnerAdapter adapter) {
         mSpinnerAdapter = adapter;
         if (mSpinner != null) {
diff --git a/core/java/com/android/internal/widget/ScrollingTabContainerView.java b/core/java/com/android/internal/widget/ScrollingTabContainerView.java
index 718d249..0e4c9ef 100644
--- a/core/java/com/android/internal/widget/ScrollingTabContainerView.java
+++ b/core/java/com/android/internal/widget/ScrollingTabContainerView.java
@@ -30,18 +30,32 @@ import android.view.Gravity;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.animation.DecelerateInterpolator;
+import android.widget.AdapterView;
+import android.widget.BaseAdapter;
 import android.widget.HorizontalScrollView;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
+import android.widget.ListView;
+import android.widget.Spinner;
 import android.widget.TextView;
 
-public class ScrollingTabContainerView extends HorizontalScrollView {
+/**
+ * This widget implements the dynamic action bar tab behavior that can change
+ * across different configurations or circumstances.
+ */
+public class ScrollingTabContainerView extends HorizontalScrollView
+        implements AdapterView.OnItemSelectedListener {
+    private static final String TAG = "ScrollingTabContainerView";
     Runnable mTabSelector;
     private TabClickListener mTabClickListener;
 
     private LinearLayout mTabLayout;
+    private Spinner mTabSpinner;
+    private boolean mAllowCollapse;
 
     int mMaxTabWidth;
+    private int mContentHeight;
+    private int mSelectedTabIndex;
 
     protected Animator mVisibilityAnim;
     protected final VisibilityAnimListener mVisAnimListener = new VisibilityAnimListener();
@@ -53,14 +67,19 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
     public ScrollingTabContainerView(Context context) {
         super(context);
         setHorizontalScrollBarEnabled(false);
+
+        mTabLayout = createTabLayout();
+        addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
+                ViewGroup.LayoutParams.MATCH_PARENT));
     }
 
     @Override
     public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
-        setFillViewport(widthMode == MeasureSpec.EXACTLY);
+        final boolean lockedExpanded = widthMode == MeasureSpec.EXACTLY;
+        setFillViewport(lockedExpanded);
 
-        final int childCount = getChildCount();
+        final int childCount = mTabLayout.getChildCount();
         if (childCount > 1 &&
                 (widthMode == MeasureSpec.EXACTLY || widthMode == MeasureSpec.AT_MOST)) {
             if (childCount > 2) {
@@ -72,14 +91,85 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
             mMaxTabWidth = -1;
         }
 
+        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
+        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
+        if (heightMode != MeasureSpec.UNSPECIFIED) {
+            if (mContentHeight == 0 && heightMode == MeasureSpec.EXACTLY) {
+                // Use this as our content height.
+                mContentHeight = heightSize;
+            }
+            heightSize = Math.min(heightSize, mContentHeight);
+            heightMeasureSpec = MeasureSpec.makeMeasureSpec(heightSize, heightMode);
+        }
+
+        final boolean canCollapse = !lockedExpanded && mAllowCollapse;
+
+        if (canCollapse) {
+            // See if we should expand
+            mTabLayout.measure(MeasureSpec.UNSPECIFIED, heightMeasureSpec);
+            if (mTabLayout.getMeasuredWidth() > MeasureSpec.getSize(widthMeasureSpec)) {
+                performCollapse();
+            } else {
+                performExpand();
+            }
+        } else {
+            performExpand();
+        }
+
+        final int oldWidth = getMeasuredWidth();
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+        final int newWidth = getMeasuredWidth();
+
+        if (lockedExpanded && oldWidth != newWidth) {
+            // Recenter the tab display if we're at a new (scrollable) size.
+            setTabSelected(mSelectedTabIndex);
+        }
     }
 
-    public void setTabSelected(int position) {
-        if (mTabLayout == null) {
-            return;
+    /**
+     * Indicates whether this view is collapsed into a dropdown menu instead
+     * of traditional tabs.
+     * @return true if showing as a spinner
+     */
+    private boolean isCollapsed() {
+        return mTabSpinner != null && mTabSpinner.getParent() == this;
+    }
+
+    public void setAllowCollapse(boolean allowCollapse) {
+        mAllowCollapse = allowCollapse;
+    }
+
+    private void performCollapse() {
+        if (isCollapsed()) return;
+
+        if (mTabSpinner == null) {
+            mTabSpinner = createSpinner();
         }
+        removeView(mTabLayout);
+        addView(mTabSpinner, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
+                ViewGroup.LayoutParams.MATCH_PARENT));
+        if (mTabSpinner.getAdapter() == null) {
+            mTabSpinner.setAdapter(new TabAdapter());
+        }
+        if (mTabSelector != null) {
+            removeCallbacks(mTabSelector);
+            mTabSelector = null;
+        }
+        mTabSpinner.setSelection(mSelectedTabIndex);
+    }
 
+    private boolean performExpand() {
+        if (!isCollapsed()) return false;
+
+        removeView(mTabSpinner);
+        addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
+                ViewGroup.LayoutParams.MATCH_PARENT));
+        setTabSelected(mTabSpinner.getSelectedItemPosition());
+        return false;
+    }
+
+    public void setTabSelected(int position) {
+        mSelectedTabIndex = position;
         final int tabCount = mTabLayout.getChildCount();
         for (int i = 0; i < tabCount; i++) {
             final View child = mTabLayout.getChildAt(i);
@@ -92,10 +182,28 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
     }
 
     public void setContentHeight(int contentHeight) {
-        mTabLayout.getLayoutParams().height = contentHeight;
+        mContentHeight = contentHeight;
         requestLayout();
     }
 
+    private LinearLayout createTabLayout() {
+        final LinearLayout tabLayout = new LinearLayout(getContext(), null,
+                com.android.internal.R.attr.actionBarTabBarStyle);
+        tabLayout.setMeasureWithLargestChildEnabled(true);
+        tabLayout.setLayoutParams(new LinearLayout.LayoutParams(
+                LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT));
+        return tabLayout;
+    }
+
+    private Spinner createSpinner() {
+        final Spinner spinner = new Spinner(getContext(), null,
+                com.android.internal.R.attr.actionDropDownStyle);
+        spinner.setLayoutParams(new LinearLayout.LayoutParams(
+                LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT));
+        spinner.setOnItemSelectedListener(this);
+        return spinner;
+    }
+
     @Override
     protected void onConfigurationChanged(Configuration newConfig) {
         super.onConfigurationChanged(newConfig);
@@ -132,7 +240,7 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
         }
     }
 
-    public void animateToTab(int position) {
+    public void animateToTab(final int position) {
         final View tabView = mTabLayout.getChildAt(position);
         if (mTabSelector != null) {
             removeCallbacks(mTabSelector);
@@ -147,22 +255,15 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
         post(mTabSelector);
     }
 
-    public void setTabLayout(LinearLayout tabLayout) {
-        if (mTabLayout != tabLayout) {
-            if (mTabLayout != null) {
-                ((ViewGroup) mTabLayout.getParent()).removeView(mTabLayout);
-            }
-            if (tabLayout != null) {
-                addView(tabLayout);
-            }
-            mTabLayout = tabLayout;
+    @Override
+    public void onAttachedToWindow() {
+        super.onAttachedToWindow();
+        if (mTabSelector != null) {
+            // Re-post the selector we saved
+            post(mTabSelector);
         }
     }
 
-    public LinearLayout getTabLayout() {
-        return mTabLayout;
-    }
-
     @Override
     public void onDetachedFromWindow() {
         super.onDetachedFromWindow();
@@ -171,61 +272,112 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
         }
     }
 
-    private TabView createTabView(ActionBar.Tab tab) {
-        final TabView tabView = new TabView(getContext(), tab);
-        tabView.setFocusable(true);
+    private TabView createTabView(ActionBar.Tab tab, boolean forAdapter) {
+        final TabView tabView = new TabView(getContext(), tab, forAdapter);
+        if (forAdapter) {
+            tabView.setBackgroundDrawable(null);
+            tabView.setLayoutParams(new ListView.LayoutParams(ListView.LayoutParams.MATCH_PARENT,
+                    mContentHeight));
+        } else {
+            tabView.setFocusable(true);
 
-        if (mTabClickListener == null) {
-            mTabClickListener = new TabClickListener();
+            if (mTabClickListener == null) {
+                mTabClickListener = new TabClickListener();
+            }
+            tabView.setOnClickListener(mTabClickListener);
         }
-        tabView.setOnClickListener(mTabClickListener);
         return tabView;
     }
 
     public void addTab(ActionBar.Tab tab, boolean setSelected) {
-        View tabView = createTabView(tab);
+        TabView tabView = createTabView(tab, false);
         mTabLayout.addView(tabView, new LinearLayout.LayoutParams(0,
                 LayoutParams.MATCH_PARENT, 1));
+        if (mTabSpinner != null) {
+            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
+        }
         if (setSelected) {
             tabView.setSelected(true);
         }
+        if (mAllowCollapse) {
+            requestLayout();
+        }
     }
 
     public void addTab(ActionBar.Tab tab, int position, boolean setSelected) {
-        final TabView tabView = createTabView(tab);
+        final TabView tabView = createTabView(tab, false);
         mTabLayout.addView(tabView, position, new LinearLayout.LayoutParams(
                 0, LayoutParams.MATCH_PARENT, 1));
+        if (mTabSpinner != null) {
+            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
+        }
         if (setSelected) {
             tabView.setSelected(true);
         }
+        if (mAllowCollapse) {
+            requestLayout();
+        }
     }
 
     public void updateTab(int position) {
         ((TabView) mTabLayout.getChildAt(position)).update();
+        if (mTabSpinner != null) {
+            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
+        }
+        if (mAllowCollapse) {
+            requestLayout();
+        }
     }
 
     public void removeTabAt(int position) {
-        if (mTabLayout != null) {
-            mTabLayout.removeViewAt(position);
+        mTabLayout.removeViewAt(position);
+        if (mTabSpinner != null) {
+            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
+        }
+        if (mAllowCollapse) {
+            requestLayout();
         }
     }
 
     public void removeAllTabs() {
-        if (mTabLayout != null) {
-            mTabLayout.removeAllViews();
+        mTabLayout.removeAllViews();
+        if (mTabSpinner != null) {
+            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
+        }
+        if (mAllowCollapse) {
+            requestLayout();
         }
     }
 
+    @Override
+    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
+        TabView tabView = (TabView) view;
+        tabView.getTab().select();
+    }
+
+    @Override
+    public void onNothingSelected(AdapterView<?> parent) {
+    }
+
     private class TabView extends LinearLayout {
         private ActionBar.Tab mTab;
         private TextView mTextView;
         private ImageView mIconView;
         private View mCustomView;
 
-        public TabView(Context context, ActionBar.Tab tab) {
+        public TabView(Context context, ActionBar.Tab tab, boolean forList) {
             super(context, null, com.android.internal.R.attr.actionBarTabStyle);
             mTab = tab;
 
+            if (forList) {
+                setGravity(Gravity.LEFT | Gravity.CENTER_VERTICAL);
+            }
+
+            update();
+        }
+
+        public void bindTab(ActionBar.Tab tab) {
+            mTab = tab;
             update();
         }
 
@@ -303,6 +455,33 @@ public class ScrollingTabContainerView extends HorizontalScrollView {
         }
     }
 
+    private class TabAdapter extends BaseAdapter {
+        @Override
+        public int getCount() {
+            return mTabLayout.getChildCount();
+        }
+
+        @Override
+        public Object getItem(int position) {
+            return ((TabView) mTabLayout.getChildAt(position)).getTab();
+        }
+
+        @Override
+        public long getItemId(int position) {
+            return position;
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            if (convertView == null) {
+                convertView = createTabView((ActionBar.Tab) getItem(position), true);
+            } else {
+                ((TabView) convertView).bindTab((ActionBar.Tab) getItem(position));
+            }
+            return convertView;
+        }
+    }
+
     private class TabClickListener implements OnClickListener {
         public void onClick(View view) {
             TabView tabView = (TabView) view;