Add titles to PreferenceFragments and PreferenceScreens for watches.

Preferences lack a title on watch type devices due to lack of ActionBar
support. A custom ListView was added to use a custom wrapper adapter to
add a persistent header view at the top of the ListView that developers
would not be able to remove via the ListView API.

Bug: 27962897
Change-Id: I6bccecf85592d9507e0c7a04c9a035617001e9ef

3 files changed, 83 insertions, 12 deletions

diff --git a/core/java/android/preference/PreferenceFragment.java b/core/java/android/preference/PreferenceFragment.java
index d4a3582cfbf6..73fa01e59201 100644
--- a/core/java/android/preference/PreferenceFragment.java
+++ b/core/java/android/preference/PreferenceFragment.java
@@ -27,12 +27,14 @@ import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
+import android.text.TextUtils;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnKeyListener;
 import android.view.ViewGroup;
 import android.widget.ListView;
+import android.widget.TextView;
 
 /**
  * Shows a hierarchy of {@link Preference} objects as
@@ -366,6 +368,20 @@ public abstract class PreferenceFragment extends Fragment implements
     private void bindPreferences() {
         final PreferenceScreen preferenceScreen = getPreferenceScreen();
         if (preferenceScreen != null) {
+            View root = getView();
+            if (root != null) {
+                View titleView = root.findViewById(android.R.id.title);
+                if (titleView instanceof TextView) {
+                    CharSequence title = preferenceScreen.getTitle();
+                    if (TextUtils.isEmpty(title)) {
+                        titleView.setVisibility(View.GONE);
+                    } else {
+                        ((TextView) titleView).setText(title);
+                        titleView.setVisibility(View.VISIBLE);
+                    }
+                }
+            }
+
             preferenceScreen.bind(getListView());
         }
         onBindPreferences();
diff --git a/core/java/android/preference/PreferenceScreen.java b/core/java/android/preference/PreferenceScreen.java
index b1317e656e3e..2305b0564e49 100644
--- a/core/java/android/preference/PreferenceScreen.java
+++ b/core/java/android/preference/PreferenceScreen.java
@@ -19,6 +19,8 @@ package android.preference;
 import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
+import android.content.res.TypedArray;
+import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -31,6 +33,7 @@ import android.widget.Adapter;
 import android.widget.AdapterView;
 import android.widget.ListAdapter;
 import android.widget.ListView;
+import android.widget.TextView;
 
 /**
  * Represents a top-level {@link Preference} that
@@ -91,13 +94,33 @@ public final class PreferenceScreen extends PreferenceGroup implements AdapterVi
     private Dialog mDialog;
 
     private ListView mListView;
-    
+
+    private int mLayoutResId = com.android.internal.R.layout.preference_list_fragment;
+    private Drawable mDividerDrawable;
+    private boolean mDividerSpecified;
+
     /**
      * Do NOT use this constructor, use {@link PreferenceManager#createPreferenceScreen(Context)}.
      * @hide-
      */
     public PreferenceScreen(Context context, AttributeSet attrs) {
         super(context, attrs, com.android.internal.R.attr.preferenceScreenStyle);
+
+        TypedArray a = context.obtainStyledAttributes(null,
+                com.android.internal.R.styleable.PreferenceScreen,
+                com.android.internal.R.attr.preferenceScreenStyle,
+                0);
+
+        mLayoutResId = a.getResourceId(
+                com.android.internal.R.styleable.PreferenceScreen_screenLayout,
+                mLayoutResId);
+        if (a.hasValueOrEmpty(com.android.internal.R.styleable.PreferenceScreen_divider)) {
+            mDividerDrawable =
+                    a.getDrawable(com.android.internal.R.styleable.PreferenceScreen_divider);
+            mDividerSpecified = true;
+        }
+
+        a.recycle();
     }
 
     /**
@@ -163,18 +186,30 @@ public final class PreferenceScreen extends PreferenceGroup implements AdapterVi
 
         LayoutInflater inflater = (LayoutInflater)
                 context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
-        View childPrefScreen = inflater.inflate(
-                com.android.internal.R.layout.preference_list_fragment, null);
+        View childPrefScreen = inflater.inflate(mLayoutResId, null);
+        View titleView = childPrefScreen.findViewById(android.R.id.title);
         mListView = (ListView) childPrefScreen.findViewById(android.R.id.list);
+        if (mDividerSpecified) {
+            mListView.setDivider(mDividerDrawable);
+        }
+
         bind(mListView);
 
         // Set the title bar if title is available, else no title bar
         final CharSequence title = getTitle();
         Dialog dialog = mDialog = new Dialog(context, context.getThemeResId());
         if (TextUtils.isEmpty(title)) {
+            if (titleView != null) {
+                titleView.setVisibility(View.GONE);
+            }
             dialog.getWindow().requestFeature(Window.FEATURE_NO_TITLE);
         } else {
-            dialog.setTitle(title);
+            if (titleView instanceof TextView) {
+                ((TextView) titleView).setText(title);
+                titleView.setVisibility(View.VISIBLE);
+            } else {
+                dialog.setTitle(title);
+            }
         }
         dialog.setContentView(childPrefScreen);
         dialog.setOnDismissListener(this);
diff --git a/core/java/android/widget/ListView.java b/core/java/android/widget/ListView.java
index 8f908fb85444..b0f19d7a0b49 100644
--- a/core/java/android/widget/ListView.java
+++ b/core/java/android/widget/ListView.java
@@ -112,8 +112,8 @@ public class ListView extends AbsListView {
         public boolean isSelectable;
     }
 
-    private ArrayList<FixedViewInfo> mHeaderViewInfos = Lists.newArrayList();
-    private ArrayList<FixedViewInfo> mFooterViewInfos = Lists.newArrayList();
+    ArrayList<FixedViewInfo> mHeaderViewInfos = Lists.newArrayList();
+    ArrayList<FixedViewInfo> mFooterViewInfos = Lists.newArrayList();
 
     Drawable mDivider;
     int mDividerHeight;
@@ -279,7 +279,7 @@ public class ListView extends AbsListView {
         // Wrap the adapter if it wasn't already wrapped.
         if (mAdapter != null) {
             if (!(mAdapter instanceof HeaderViewListAdapter)) {
-                mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
+                wrapHeaderListAdapterInternal();
             }
 
             // In the case of re-adding a header view, or adding one later on,
@@ -373,7 +373,7 @@ public class ListView extends AbsListView {
         // Wrap the adapter if it wasn't already wrapped.
         if (mAdapter != null) {
             if (!(mAdapter instanceof HeaderViewListAdapter)) {
-                mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
+                wrapHeaderListAdapterInternal();
             }
 
             // In the case of re-adding a footer view, or adding one later on,
@@ -476,7 +476,7 @@ public class ListView extends AbsListView {
         mRecycler.clear();
 
         if (mHeaderViewInfos.size() > 0|| mFooterViewInfos.size() > 0) {
-            mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, adapter);
+            mAdapter = wrapHeaderListAdapterInternal(mHeaderViewInfos, mFooterViewInfos, adapter);
         } else {
             mAdapter = adapter;
         }
@@ -2228,7 +2228,7 @@ public class ListView extends AbsListView {
      * after the header views.
      */
     public void setSelectionAfterHeaderView() {
-        final int count = mHeaderViewInfos.size();
+        final int count = getHeaderViewsCount();
         if (count > 0) {
             mNextSelectedPosition = 0;
             return;
@@ -3356,7 +3356,7 @@ public class ListView extends AbsListView {
             bounds.right = mRight - mLeft - mPaddingRight;
 
             final int count = getChildCount();
-            final int headerCount = mHeaderViewInfos.size();
+            final int headerCount = getHeaderViewsCount();
             final int itemCount = mItemCount;
             final int footerLimit = (itemCount - mFooterViewInfos.size());
             final boolean headerDividers = mHeaderDividersEnabled;
@@ -3940,7 +3940,7 @@ public class ListView extends AbsListView {
         if (drawDividers) {
             final boolean fillForMissingDividers = isOpaque() && !super.isOpaque();
             final int itemCount = mItemCount;
-            final int headerCount = mHeaderViewInfos.size();
+            final int headerCount = getHeaderViewsCount();
             final int footerLimit = (itemCount - mFooterViewInfos.size());
             final boolean isHeader = (itemIndex < headerCount);
             final boolean isFooter = (itemIndex >= footerLimit);
@@ -4052,4 +4052,24 @@ public class ListView extends AbsListView {
 
         encoder.addProperty("recycleOnMeasure", recycleOnMeasure());
     }
+
+    /** @hide */
+    protected HeaderViewListAdapter wrapHeaderListAdapterInternal(
+            ArrayList<ListView.FixedViewInfo> headerViewInfos,
+            ArrayList<ListView.FixedViewInfo> footerViewInfos,
+            ListAdapter adapter) {
+        return new HeaderViewListAdapter(headerViewInfos, footerViewInfos, adapter);
+    }
+
+    /** @hide */
+    protected void wrapHeaderListAdapterInternal() {
+        mAdapter = wrapHeaderListAdapterInternal(mHeaderViewInfos, mFooterViewInfos, mAdapter);
+    }
+
+    /** @hide */
+    protected void dispatchDataSetObserverOnChangedInternal() {
+        if (mDataSetObserver != null) {
+            mDataSetObserver.onChanged();
+        }
+    }
 }