Optimize the connection steps

src/connectiontablemodel.cpp

@@ -149,3 +149,15 @@ void ConnectionTableModel::onConnectionLatencyChanged()
     int row = items.indexOf(item);
     emit dataChanged(this->index(row, 3), this->index(row, 3));
 }
+
+ConnectionItem* ConnectionTableModel::getRunningItem() const
+{
+    for (auto &i : items) {
+        Connection *conn = i->getConnection();
+        if (conn && conn->isRunning()) {
+            return i;
+        }
+    }
+
+    return NULL;
+}

src/connectiontablemodel.h

@@ -32,6 +32,7 @@ class ConnectionTableModel : public QAbstractTableModel
     ~ConnectionTableModel();
 
     ConnectionItem *getItem(const int &row) const;
+    ConnectionItem* getRunningItem() const;
     int rowCount(const QModelIndex &parent = QModelIndex()) const Q_DECL_OVERRIDE;
     int columnCount(const QModelIndex &parent = QModelIndex()) const Q_DECL_OVERRIDE;
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const Q_DECL_OVERRIDE;

src/mainwindow.cpp

@@ -296,6 +296,12 @@ void MainWindow::onConnect()
 {
     int row = proxyModel->mapToSource(ui->connectionView->currentIndex()).row();
     Connection *con = model->getItem(row)->getConnection();
+
+    ConnectionItem* item = model->getRunningItem();
+    if (item && item != model->getItem(row)) {
+        item->getConnection()->stop();
+    }
+
     if (con->isValid()) {
         con->start();
     } else {