Add API demo for WindowInputToken.

Change-Id: I2c1521caa30545411f34e57ad2f5eceb16c0b2b1

samples/ApiDemos/src/com/example/android/apis/view/WindowFocusObserver.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2011 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.apis.view;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.net.Uri;
+import android.os.Bundle;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
+import android.view.WindowId;
+import android.view.WindowId.FocusObserver;
+import android.widget.SearchView;
+import android.widget.ShareActionProvider;
+import android.widget.TextView;
+import android.widget.Toast;
+import com.example.android.apis.R;
+
+public class WindowFocusObserver extends Activity implements SearchView.OnQueryTextListener {
+    TextView mState;
+
+    final FocusObserver mObserver = new WindowId.FocusObserver() {
+
+        @Override
+        public void onFocusGained(WindowId token) {
+            mState.setText("Gained focus");
+        }
+
+        @Override
+        public void onFocusLost(WindowId token) {
+            mState.setText("Lost focus");
+        }
+    };
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        setContentView(R.layout.window_focus_observer);
+        mState = (TextView)findViewById(R.id.focus_state);
+    }
+
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        MenuInflater inflater = getMenuInflater();
+        inflater.inflate(R.menu.content_actions, menu);
+        SearchView searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();
+        searchView.setOnQueryTextListener(this);
+
+        // Set file with share history to the provider and set the share intent.
+        MenuItem actionItem = menu.findItem(R.id.menu_item_share_action_provider_action_bar);
+        ShareActionProvider actionProvider = (ShareActionProvider) actionItem.getActionProvider();
+        actionProvider.setShareHistoryFileName(ShareActionProvider.DEFAULT_SHARE_HISTORY_FILE_NAME);
+        // Note that you can set/change the intent any time,
+        // say when the user has selected an image.
+        Intent shareIntent = new Intent(Intent.ACTION_SEND);
+        shareIntent.setType("image/*");
+        Uri uri = Uri.fromFile(getFileStreamPath("shared.png"));
+        shareIntent.putExtra(Intent.EXTRA_STREAM, uri);
+        actionProvider.setShareIntent(shareIntent);
+        return true;
+    }
+
+    public void onSort(MenuItem item) {
+    }
+
+    @Override
+    public boolean onQueryTextChange(String newText) {
+        return true;
+    }
+
+    @Override
+    public boolean onQueryTextSubmit(String query) {
+        Toast.makeText(this, "Searching for: " + query + "...", Toast.LENGTH_SHORT).show();
+        return true;
+    }
+
+    @Override
+    public void onAttachedToWindow() {
+        super.onAttachedToWindow();
+        WindowId token = getWindow().getDecorView().getWindowId();
+        token.registerFocusObserver(mObserver);
+        mState.setText(token.isFocused() ? "Focused" : "Not focused");
+    }
+
+    @Override
+    public void onDetachedFromWindow() {
+        super.onDetachedFromWindow();
+        getWindow().getDecorView().getWindowId().unregisterFocusObserver(mObserver);
+    }
+}