Add AppNavigation demo

This demo illustrates the use of the new support library functionality
for navigating within and across tasks using "up" navigation. This
matches the recommendations in the Android design guide.

Change-Id: I2b36c962dd24f0e0f3b3ee3f86319dafc2fc66e2
diff --git a/samples/AppNavigation/src/com/example/android/appnavigation/app/InterstitialMessageActivity.java b/samples/AppNavigation/src/com/example/android/appnavigation/app/InterstitialMessageActivity.java
new file mode 100644
index 0000000..1d0154d
--- /dev/null
+++ b/samples/AppNavigation/src/com/example/android/appnavigation/app/InterstitialMessageActivity.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2012 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.example.android.appnavigation.app;
+
+import com.example.android.appnavigation.R;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.os.Bundle;
+import android.support.v4.app.TaskStackBuilder;
+import android.view.View;
+
+public class InterstitialMessageActivity extends Activity {
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.interstitial_message);
+    }
+
+    public void onViewContent(View v) {
+        TaskStackBuilder.from(this)
+                .addParentStack(ContentViewActivity.class)
+                .addNextIntent(new Intent(this, ContentViewActivity.class)
+                        .putExtra(ContentViewActivity.EXTRA_TEXT, "From Interstitial Notification"))
+                .startActivities();
+        finish();
+    }
+}