Support asynchronuous spawnDomFunction.

samples/isolate_html/isolate_sample.dart

Index: samples/isolate_html/isolate_sample.dart
diff --git a/samples/isolate_html/isolate_sample.dart b/samples/isolate_html/isolate_sample.dart
index 4f239a8811329435a40c7afd7fbf8ffdb846e733..81437ef8bab8b5bb9c275859a8e45bc3e20aaea2 100644
--- a/samples/isolate_html/isolate_sample.dart
+++ b/samples/isolate_html/isolate_sample.dart
@@ -27,14 +27,15 @@ class MessageId {
  * them names in this app so we can show which isolate is doing
  * what.
  */
-SendPort createIsolate(String name) {
-  var sendPort = spawnDomFunction(isolateMain);
-  var message = {
-    'id' : MessageId.INIT,
-    'args' : [name, port.toSendPort()]
-  };
-  sendPort.send(message, null);
-  return sendPort;
+Future<SendPort> createIsolate(String name) {
+  return spawnDomFunction(isolateMain).transform((sendPort) {

[vsm, 2013/03/26 19:13:37]

transform -> then? 

[Anton Muhin, 2013/03/26 19:15:37]

I have to return a future as well, hence I used transform.  Is there a way to
use .then here?

[vsm, 2013/03/26 19:21:39]

Future.then returns a Future.  I don't see transform defined on Future.

On 2013/03/26 19:15:37, Anton Muhin wrote:

[Anton Muhin, 2013/03/27 08:41:46]

You're absolutely right, sorry, got confused.

On 2013/03/26 19:21:39, vsm wrote:

+    var message = {
+      'id' : MessageId.INIT,
+      'args' : [name, port.toSendPort()]
+    };
+    sendPort.send(message, null);
+    return sendPort;
+  });
 }
 
 // TODO(mattsh) get this off the System object once it's available
@@ -103,24 +104,28 @@ main() {
 
   var replyElement = query('.isolateMain .replyText');
 
-  ports['A'] = createIsolate('A');
-  ports['B'] = createIsolate('B');
-
-  for (var element in queryAll('.sendButton')) {
-    element.onClick.listen((Event e) {
-      replyElement.text = 'waiting for reply...';
+  createIsolate('A').then((sendPortA) {
+    ports['A'] = sendPortA;
+    createIsolate('B').then((sendPortB) {
+      ports['B'] = sendPortB;
+
+      for (var element in queryAll('.sendButton')) {
+        element.onClick.listen((Event e) {
+          replyElement.text = 'waiting for reply...';
+
+          var isolateName =
+              (e.currentTarget as Element).attributes['data-isolate-name'];
+          var greeting = query('input#greetingText').value;
+          var message = {'id': MessageId.GREETING, 'args': [greeting]};
+          ports[isolateName].call(message).then((var msg) {
+            replyElement.text = msg;
+          });
+        });
+      }
 
-      var isolateName =
-          (e.currentTarget as Element).attributes['data-isolate-name'];
-      var greeting = query('input#greetingText').value;
-      var message = {'id': MessageId.GREETING, 'args': [greeting]};
-      ports[isolateName].call(message).then((var msg) {
-        replyElement.text = msg;
+      port.receive((var message, SendPort replyTo) {
+        replyElement.text = message;
       });
     });
-  }
-
-  port.receive((var message, SendPort replyTo) {
-    replyElement.text = message;
   });
 }