Add the capability to set a pinned header to a ListFragment

- add public void setPinnedHeaderView(View pinnedHeader) and
clearPinnedHeaderView() APIs for adding and clearing the pinned header

Change-Id: I1096b418351c0f02a13fd49d4a19e52970125106

src/com/android/settings/PinnedHeaderListFragment.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings;
+
+import android.app.ListFragment;
+import android.view.View;
+import android.view.ViewGroup;
+
+/**
+ * A ListFragment with a pinned header
+ */
+public class PinnedHeaderListFragment extends ListFragment {
+
+    public PinnedHeaderListFragment() {
+        super();
+    }
+
+    /**
+     * Set the pinned header view. This can only be done when the ListView is already created.
+     *
+     * @param pinnedHeaderView the view to be used for the pinned header view.
+     */
+    public void setPinnedHeaderView(View pinnedHeaderView) {
+        ((ViewGroup) getListView().getParent()).addView(pinnedHeaderView, 0);
+    }
+
+    /**
+     * Clear the pinned header view. This can only be done when the ListView is already created.
+     */
+    public void clearPinnedHeaderView() {
+        ((ViewGroup) getListView().getParent()).removeViewAt(0);
+    }
+}