commit e8b9e8e0faf85bb8b8a347c246226949cd009272
author Zhenkai Zhu <zhenkai@cs.ucla.edu> Mon Jun 04 21:55:14 2012 -0700
committer Zhenkai Zhu <zhenkai@cs.ucla.edu> Mon Jun 04 21:55:14 2012 -0700
tree f79b19233ee796ab8fa793c1af3de5f9e17840b4
parent 88380c133e3eea3243c6b3d7d535a6188453ad35

don't crash anymore;
all message received, but is not correctly displayed

demo/chatdialog.cpp

diff --git a/demo/chatdialog.cpp b/demo/chatdialog.cpp
index 0704ddd..5527f96 100644
--- a/demo/chatdialog.cpp
+++ b/demo/chatdialog.cpp
@@ -4,6 +4,7 @@
 #include <ctime>
 #include <iostream>
 #include <QTimer>
+#include <QMetaType>
 
 #define BROADCAST_PREFIX_FOR_SYNC_DEMO "/ndn/broadcast/sync-demo"
 
@@ -32,6 +33,9 @@
 ChatDialog::ChatDialog(QWidget *parent)
   : QDialog(parent), m_sock(NULL)
 {
+  // have to register this, otherwise
+  // the signal-slot system won't recognize this type
+  qRegisterMetaType<SyncDemo::ChatMessage>("SyncDemo::ChatMessage");
   setupUi(this);
   m_session = time(NULL);
 
@@ -57,7 +61,8 @@
 
   connect(lineEdit, SIGNAL(returnPressed()), this, SLOT(returnPressed()));
   connect(setButton, SIGNAL(pressed()), this, SLOT(buttonPressed()));
-  testDraw();
+  connect(this, SIGNAL(msgReceived(const SyncDemo::ChatMessage)), this, SLOT(appendMessage(const SyncDemo::ChatMessage)));
+  //testDraw();
 }
 
 ChatDialog::~ChatDialog()
@@ -70,7 +75,7 @@
 }
 
 void
-ChatDialog::appendMessage(const SyncDemo::ChatMessage &msg) 
+ChatDialog::appendMessage(const SyncDemo::ChatMessage msg) 
 {
 
   if (msg.type() != SyncDemo::ChatMessage::CHAT) {
@@ -85,6 +90,7 @@
     return;
   }
 
+  std::cout << "<<<< Received Message: " << msg.data() << std::endl;
   QTextCursor cursor(textEdit->textCursor());
   cursor.movePosition(QTextCursor::End);
   QTextTableFormat tableFormat;
@@ -95,6 +101,7 @@
   table->cellAt(0, 1).firstCursorPosition().insertText(msg.data().c_str());
   QScrollBar *bar = textEdit->verticalScrollBar();
   bar->setValue(bar->maximum());
+  std::cout << "<<<<, Message appended " << std::endl;
 }
 
 void
@@ -147,8 +154,12 @@
     abort();
   }
 
-  // display
-  appendMessage(msg);
+  // display msg received from network
+  // we have to do so; this function is called by ccnd thread
+  // so if we call appendMsg directly
+  // Qt crash as "QObject: Cannot create children for a parent that is in a different thread"
+  // the "cannonical" way to is use signal-slot
+  emit msgReceived(msg);
   
   // update the tree view
   std::string prefix = name.substr(0, name.find_last_of('/'));

demo/chatdialog.h

diff --git a/demo/chatdialog.h b/demo/chatdialog.h
index ea95873..df3de48 100644
--- a/demo/chatdialog.h
+++ b/demo/chatdialog.h
@@ -19,11 +19,13 @@
 public:
 	ChatDialog(QWidget *parent = 0);
   ~ChatDialog();
-  void appendMessage(const SyncDemo::ChatMessage &msg);
   void processTreeUpdate(const std::vector<Sync::MissingDataInfo> &, Sync::SyncAppSocket *);
   void processData(std::string, const char *buf, size_t len);
   void processRemove(const std::string);
 
+public slots:
+  void appendMessage(const SyncDemo::ChatMessage msg);
+
 private:
   void formChatMessage(const QString &text, SyncDemo::ChatMessage &msg);
   bool readSettings();
@@ -39,6 +41,9 @@
   void buttonPressed();
   void settingUpdated(QString, QString, QString);
 
+signals:
+  void msgReceived(const SyncDemo::ChatMessage msg);
+
 private:
   User m_user; 
   Sync::SyncAppSocket *m_sock;