added a hander for returnPressed() in QLineEdit of GUI

chat_window.hpp

@@ -10,17 +10,24 @@ class chat_window : public QWidget
 {
     Q_OBJECT
 
-public:
-    explicit chat_window(QWidget* parent = 0)
-    :QWidget(parent)
-    { setupUi(); }
-
-private:
     QGridLayout* _layout;
     QListWidget* _chat;
     QListWidget* _people;
     QLineEdit* _msg;
 
+public:
+    explicit chat_window(QWidget* parent = 0)
+    :QWidget(parent)
+    { setupUi(); }
+
+public slots:
+    void return_handler()
+    {
+        _chat->addItem(_msg->text());
+        _msg->clear();
+    };
+
+private:
     void setupUi()
     {
         this->setWindowTitle("C++11Chat");
@@ -31,6 +38,7 @@ private:
         _people = new QListWidget();
 
         _msg = new QLineEdit();
+        connect(_msg, &QLineEdit::returnPressed, this, &chat_window::return_handler);
 
         _layout->addWidget(_chat, 0, 0, 1, 1);
         _layout->addWidget(_people, 0, 1, 1, 2);