Clarify connections between webview and webchannel.

We register objects once after the webchannel has initialized.
The web view URL on the other hand gets changed via property
binding after the web channel's base url is set/modified.

This hopefully fixes a race condition between the client-side HTML
logic and the registering of objects on the host-side QML app.

Change-Id: Ie83f7a415d9005e805a544f25287e51e75fb4dec
Reviewed-by: Pierre Rossi <pierre.rossi@gmail.com>

3 files changed, 4 insertions, 2 deletions

diff --git a/examples/qtobject/qml/qtobject/main.qml b/examples/qtobject/qml/qtobject/main.qml
index 05591a8..2ca26ec 100644
--- a/examples/qtobject/qml/qtobject/main.qml
+++ b/examples/qtobject/qml/qtobject/main.qml
@@ -75,15 +75,15 @@ Rectangle {
             }
         }
 
-        onBaseUrlChanged: publisher.registerObjects({"testObject1": testObject1, "testObject2": testObject2, "testObject3":testObject3})
+        onInitialized: publisher.registerObjects({"testObject1": testObject1, "testObject2": testObject2, "testObject3":testObject3});
     }
 
     width: 480
     height: 800
 
     WebView {
+        url: webChannel.baseUrl ? "index.html?webChannelBaseUrl=" + webChannel.baseUrl : "about:blank"
         anchors.fill: parent
-        url: "index.html?webChannelBaseUrl=" + webChannel.baseUrl
         experimental.preferences.developerExtrasEnabled: true
     }
 }
diff --git a/src/qwebchannel.cpp b/src/qwebchannel.cpp
index ee03cf8..d51dd72 100644
--- a/src/qwebchannel.cpp
+++ b/src/qwebchannel.cpp
@@ -442,6 +442,7 @@ void QWebChannel::setMaxPort(int p)
 
 void QWebChannel::onInitialized()
 {
+    emit initialized();
     emit baseUrlChanged(d->baseUrl);
 }
 
diff --git a/src/qwebchannel.h b/src/qwebchannel.h
index c3f90d9..b564787 100644
--- a/src/qwebchannel.h
+++ b/src/qwebchannel.h
@@ -106,6 +106,7 @@ signals:
     // To be able to access the object from QML, it has to be an explicit QObject* and not a subclass.
     void execute(const QString& requestData, QObject* response);
     void noPortAvailable();
+    void initialized();
 
 public slots:
     void broadcast(const QString& id, const QString& data);