Adds trunk/talk folder of revision 359 from libjingles google code to

trunk/talk


git-svn-id: http://webrtc.googlecode.com/svn/trunk@4318 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/examples/android/src/org/appspot/apprtc/GAEChannelClient.java

@@ -0,0 +1,164 @@
+/*
+ * libjingle
+ * Copyright 2013, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.appspot.apprtc;
+
+import android.annotation.SuppressLint;
+import android.app.Activity;
+import android.util.Log;
+import android.webkit.ConsoleMessage;
+import android.webkit.JavascriptInterface;
+import android.webkit.WebChromeClient;
+import android.webkit.WebView;
+import android.webkit.WebViewClient;
+
+/**
+ * Java-land version of Google AppEngine's JavaScript Channel API:
+ * https://developers.google.com/appengine/docs/python/channel/javascript
+ *
+ * Requires a hosted HTML page that opens the desired channel and dispatches JS
+ * on{Open,Message,Close,Error}() events to a global object named
+ * "androidMessageHandler".
+ */
+public class GAEChannelClient {
+  private static final String TAG = "GAEChannelClient";
+  private WebView webView;
+  private final ProxyingMessageHandler proxyingMessageHandler;
+
+  /**
+   * Callback interface for messages delivered on the Google AppEngine channel.
+   *
+   * Methods are guaranteed to be invoked on the UI thread of |activity| passed
+   * to GAEChannelClient's constructor.
+   */
+  public interface MessageHandler {
+    public void onOpen();
+    public void onMessage(String data);
+    public void onClose();
+    public void onError(int code, String description);
+  }
+
+  /** Asynchronously open an AppEngine channel. */
+  @SuppressLint("SetJavaScriptEnabled")
+  public GAEChannelClient(
+      Activity activity, String token, MessageHandler handler) {
+    webView = new WebView(activity);
+    webView.getSettings().setJavaScriptEnabled(true);
+    webView.setWebChromeClient(new WebChromeClient() {  // Purely for debugging.
+        public boolean onConsoleMessage (ConsoleMessage msg) {
+          Log.d(TAG, "console: " + msg.message() + " at " +
+              msg.sourceId() + ":" + msg.lineNumber());
+          return false;
+        }
+      });
+    webView.setWebViewClient(new WebViewClient() {  // Purely for debugging.
+        public void onReceivedError(
+            WebView view, int errorCode, String description,
+            String failingUrl) {
+          Log.e(TAG, "JS error: " + errorCode + " in " + failingUrl +
+              ", desc: " + description);
+        }
+      });
+    proxyingMessageHandler = new ProxyingMessageHandler(activity, handler);
+    webView.addJavascriptInterface(
+        proxyingMessageHandler, "androidMessageHandler");
+    webView.loadUrl("file:///android_asset/channel.html?token=" + token);
+  }
+
+  /** Close the connection to the AppEngine channel. */
+  public void close() {
+    if (webView == null) {
+      return;
+    }
+    proxyingMessageHandler.disconnect();
+    webView.removeJavascriptInterface("androidMessageHandler");
+    webView.loadUrl("about:blank");
+    webView = null;
+  }
+
+  // Helper class for proxying callbacks from the Java<->JS interaction
+  // (private, background) thread to the Activity's UI thread.
+  private static class ProxyingMessageHandler {
+    private final Activity activity;
+    private final MessageHandler handler;
+    private final boolean[] disconnected = { false };
+
+    public ProxyingMessageHandler(Activity activity, MessageHandler handler) {
+      this.activity = activity;
+      this.handler = handler;
+    }
+
+    public void disconnect() {
+      disconnected[0] = true;
+    }
+
+    private boolean disconnected() {
+      return disconnected[0];
+    }
+
+    @JavascriptInterface public void onOpen() {
+      activity.runOnUiThread(new Runnable() {
+          public void run() {
+            if (!disconnected()) {
+              handler.onOpen();
+            }
+          }
+        });
+    }
+
+    @JavascriptInterface public void onMessage(final String data) {
+      activity.runOnUiThread(new Runnable() {
+          public void run() {
+            if (!disconnected()) {
+              handler.onMessage(data);
+            }
+          }
+        });
+    }
+
+    @JavascriptInterface public void onClose() {
+      activity.runOnUiThread(new Runnable() {
+          public void run() {
+            if (!disconnected()) {
+              handler.onClose();
+            }
+          }
+        });
+    }
+
+    @JavascriptInterface public void onError(
+        final int code, final String description) {
+      activity.runOnUiThread(new Runnable() {
+          public void run() {
+            if (!disconnected()) {
+              handler.onError(code, description);
+            }
+          }
+        });
+    }
+  }
+}