diff --git a/tools/cabana/mainwin.cc b/tools/cabana/mainwin.cc
index be643c58d9..d3d7ff4156 100644
--- a/tools/cabana/mainwin.cc
+++ b/tools/cabana/mainwin.cc
@@ -1,7 +1,13 @@
 #include "tools/cabana/mainwin.h"
 
 #include <QApplication>
+#include <QCompleter>
+#include <QDialogButtonBox>
+#include <QFile>
+#include <QFileDialog>
+#include <QFileInfo>
 #include <QHBoxLayout>
+#include <QPushButton>
 #include <QScreen>
 #include <QVBoxLayout>
 
@@ -23,8 +29,38 @@ MainWindow::MainWindow() : QWidget() {
 
   splitter = new QSplitter(Qt::Horizontal, this);
   splitter->setHandleWidth(11);
+
+  // DBC file selector
+  QWidget *messages_container = new QWidget(this);
+  QVBoxLayout *messages_layout = new QVBoxLayout(messages_container);
+  messages_layout->setContentsMargins(0, 0, 0, 0);
+  QHBoxLayout *dbc_file_layout = new QHBoxLayout();
+  dbc_combo = new QComboBox(this);
+  auto dbc_names = dbc()->allDBCNames();
+  for (const auto &name : dbc_names) {
+    dbc_combo->addItem(QString::fromStdString(name));
+  }
+  dbc_combo->model()->sort(0);
+  dbc_combo->setEditable(true);
+  dbc_combo->setCurrentText(QString());
+  dbc_combo->setInsertPolicy(QComboBox::NoInsert);
+  dbc_combo->completer()->setCompletionMode(QCompleter::PopupCompletion);
+  QFont font;
+  font.setBold(true);
+  dbc_combo->lineEdit()->setFont(font);
+  dbc_file_layout->addWidget(dbc_combo);
+
+  QPushButton *load_from_paste = new QPushButton(tr("Load from paste"), this);
+  dbc_file_layout->addWidget(load_from_paste);
+
+  dbc_file_layout->addStretch();
+  QPushButton *save_btn = new QPushButton(tr("Save DBC"), this);
+  dbc_file_layout->addWidget(save_btn);
+  messages_layout->addLayout(dbc_file_layout);
+
   messages_widget = new MessagesWidget(this);
-  splitter->addWidget(messages_widget);
+  messages_layout->addWidget(messages_widget);
+  splitter->addWidget(messages_container);
 
   charts_widget = new ChartsWidget(this);
   detail_widget = new DetailWidget(charts_widget, this);
@@ -78,16 +114,55 @@ MainWindow::MainWindow() : QWidget() {
     emit updateProgressBar(cur, total, success);
   });
 
+  main_win = this;
+  qInstallMessageHandler(qLogMessageHandler);
+  QFile json_file("./car_fingerprint_to_dbc.json");
+  if (json_file.open(QIODevice::ReadOnly)) {
+    fingerprint_to_dbc = QJsonDocument::fromJson(json_file.readAll());
+  }
+
+  QObject::connect(dbc_combo, SIGNAL(activated(const QString &)), SLOT(loadDBCFromName(const QString &)));
+  QObject::connect(load_from_paste, &QPushButton::clicked, this, &MainWindow::loadDBCFromPaste);
+  QObject::connect(save_btn, &QPushButton::clicked, this, &MainWindow::saveDBC);
   QObject::connect(this, &MainWindow::showMessage, status_bar, &QStatusBar::showMessage);
   QObject::connect(this, &MainWindow::updateProgressBar, this, &MainWindow::updateDownloadProgress);
   QObject::connect(messages_widget, &MessagesWidget::msgSelectionChanged, detail_widget, &DetailWidget::setMessage);
   QObject::connect(charts_widget, &ChartsWidget::dock, this, &MainWindow::dockCharts);
   QObject::connect(charts_widget, &ChartsWidget::rangeChanged, video_widget, &VideoWidget::rangeChanged);
   QObject::connect(settings_btn, &QPushButton::clicked, this, &MainWindow::setOption);
+  QObject::connect(can, &CANMessages::streamStarted, this, &MainWindow::loadDBCFromFingerprint);
   QObject::connect(can, &CANMessages::streamStarted, [=]() { fingerprint_label->setText(can->carFingerprint() ); });
+}
 
-  main_win = this;
-  qInstallMessageHandler(qLogMessageHandler);
+void MainWindow::loadDBCFromName(const QString &name) {
+  if (name != dbc()->name()) {
+    dbc()->open(name);
+    dbc_combo->setCurrentText(name);
+  }
+}
+
+void MainWindow::loadDBCFromPaste() {
+  LoadDBCDialog dlg(this);
+  if (dlg.exec()) {
+    dbc()->open("from paste", dlg.dbc_edit->toPlainText());
+    dbc_combo->setCurrentText("loaded from paste");
+  }
+}
+
+void MainWindow::loadDBCFromFingerprint() {
+  auto fingerprint = can->carFingerprint();
+  if (!fingerprint.isEmpty() && dbc()->name().isEmpty()) {
+    auto dbc_name = fingerprint_to_dbc[fingerprint];
+    if (dbc_name != QJsonValue::Undefined) {
+      loadDBCFromName(dbc_name.toString());
+    }
+  }
+}
+
+void MainWindow::saveDBC() {
+  SaveDBCDialog dlg(this);
+  dlg.dbc_edit->setText(dbc()->generateDBC());
+  dlg.exec();
 }
 
 void MainWindow::updateDownloadProgress(uint64_t cur, uint64_t total, bool success) {
@@ -127,3 +202,60 @@ void MainWindow::setOption() {
   SettingsDlg dlg(this);
   dlg.exec();
 }
+
+// LoadDBCDialog
+
+LoadDBCDialog::LoadDBCDialog(QWidget *parent) : QDialog(parent) {
+  QVBoxLayout *main_layout = new QVBoxLayout(this);
+  dbc_edit = new QTextEdit(this);
+  dbc_edit->setAcceptRichText(false);
+  dbc_edit->setPlaceholderText(tr("paste DBC file here"));
+  main_layout->addWidget(dbc_edit);
+  auto buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
+  main_layout->addWidget(buttonBox);
+
+  setMinimumSize({640, 480});
+  QObject::connect(buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept);
+  QObject::connect(buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject);
+}
+
+// SaveDBCDialog
+
+SaveDBCDialog::SaveDBCDialog(QWidget *parent) : QDialog(parent) {
+  setWindowTitle(tr("Save DBC"));
+  QVBoxLayout *main_layout = new QVBoxLayout(this);
+  dbc_edit = new QTextEdit(this);
+  dbc_edit->setAcceptRichText(false);
+  main_layout->addWidget(dbc_edit);
+
+  QPushButton *copy_to_clipboard = new QPushButton(tr("Copy To Clipboard"), this);
+  QPushButton *save_as = new QPushButton(tr("Save As"), this);
+
+  QHBoxLayout *btn_layout = new QHBoxLayout();
+  btn_layout->addStretch();
+  btn_layout->addWidget(copy_to_clipboard);
+  btn_layout->addWidget(save_as);
+  main_layout->addLayout(btn_layout);
+  setMinimumSize({640, 480});
+
+  QObject::connect(copy_to_clipboard, &QPushButton::clicked, this, &SaveDBCDialog::copytoClipboard);
+  QObject::connect(save_as, &QPushButton::clicked, this, &SaveDBCDialog::saveAs);
+}
+
+void SaveDBCDialog::copytoClipboard() {
+  dbc_edit->selectAll();
+  dbc_edit->copy();
+  QDialog::accept();
+}
+
+void SaveDBCDialog::saveAs() {
+  QString file_name = QFileDialog::getSaveFileName(this, tr("Save File"),
+                                                   QDir::homePath() + "/untitled.dbc", tr("DBC (*.dbc)"));
+  if (!file_name.isEmpty()) {
+    QFile file(file_name);
+    if (file.open(QIODevice::WriteOnly)) {
+      file.write(dbc_edit->toPlainText().toUtf8());
+    }
+    QDialog::accept();
+  }
+}
diff --git a/tools/cabana/mainwin.h b/tools/cabana/mainwin.h
index b77744ba9c..f6853a5ea3 100644
--- a/tools/cabana/mainwin.h
+++ b/tools/cabana/mainwin.h
@@ -1,8 +1,12 @@
 #pragma once
 
+#include <QComboBox>
+#include <QDialog>
+#include <QJsonDocument>
 #include <QProgressBar>
 #include <QSplitter>
 #include <QStatusBar>
+#include <QTextEdit>
 
 #include "tools/cabana/chartswidget.h"
 #include "tools/cabana/detailwidget.h"
@@ -17,6 +21,12 @@ public:
   void dockCharts(bool dock);
   void showStatusMessage(const QString &msg, int timeout = 0) { status_bar->showMessage(msg, timeout); }
 
+public slots:
+  void loadDBCFromName(const QString &name);
+  void loadDBCFromFingerprint();
+  void loadDBCFromPaste();
+  void saveDBC();
+
 signals:
   void showMessage(const QString &msg, int timeout);
   void updateProgressBar(uint64_t cur, uint64_t total, bool success);
@@ -35,4 +45,25 @@ protected:
   QVBoxLayout *r_layout;
   QProgressBar *progress_bar;
   QStatusBar *status_bar;
+  QJsonDocument fingerprint_to_dbc;
+  QComboBox *dbc_combo;
+};
+
+
+class LoadDBCDialog : public QDialog {
+  Q_OBJECT
+
+public:
+  LoadDBCDialog(QWidget *parent);
+  QTextEdit *dbc_edit;
+};
+
+class SaveDBCDialog : public QDialog {
+  Q_OBJECT
+
+public:
+  SaveDBCDialog(QWidget *parent);
+  void copytoClipboard();
+  void saveAs();
+  QTextEdit *dbc_edit;
 };
diff --git a/tools/cabana/messageswidget.cc b/tools/cabana/messageswidget.cc
index 9444ea9c48..b2e8e50b55 100644
--- a/tools/cabana/messageswidget.cc
+++ b/tools/cabana/messageswidget.cc
@@ -1,15 +1,8 @@
 #include "tools/cabana/messageswidget.h"
 
-#include <QCompleter>
-#include <QDialogButtonBox>
-#include <QFile>
-#include <QFileDialog>
-#include <QFileInfo>
 #include <QFontDatabase>
 #include <QHeaderView>
 #include <QLineEdit>
-#include <QPushButton>
-#include <QTextEdit>
 #include <QVBoxLayout>
 
 #include "tools/cabana/dbcmanager.h"
@@ -18,31 +11,6 @@ MessagesWidget::MessagesWidget(QWidget *parent) : QWidget(parent) {
   QVBoxLayout *main_layout = new QVBoxLayout(this);
   main_layout->setContentsMargins(0, 0, 0, 0);
 
-  // DBC file selector
-  QHBoxLayout *dbc_file_layout = new QHBoxLayout();
-  dbc_combo = new QComboBox(this);
-  auto dbc_names = dbc()->allDBCNames();
-  for (const auto &name : dbc_names) {
-    dbc_combo->addItem(QString::fromStdString(name));
-  }
-  dbc_combo->model()->sort(0);
-  dbc_combo->setEditable(true);
-  dbc_combo->setCurrentText(QString());
-  dbc_combo->setInsertPolicy(QComboBox::NoInsert);
-  dbc_combo->completer()->setCompletionMode(QCompleter::PopupCompletion);
-  QFont font;
-  font.setBold(true);
-  dbc_combo->lineEdit()->setFont(font);
-  dbc_file_layout->addWidget(dbc_combo);
-
-  QPushButton *load_from_paste = new QPushButton(tr("Load from paste"), this);
-  dbc_file_layout->addWidget(load_from_paste);
-
-  dbc_file_layout->addStretch();
-  QPushButton *save_btn = new QPushButton(tr("Save DBC"), this);
-  dbc_file_layout->addWidget(save_btn);
-  main_layout->addLayout(dbc_file_layout);
-
   // message filter
   QLineEdit *filter = new QLineEdit(this);
   filter->setClearButtonEnabled(true);
@@ -67,55 +35,13 @@ MessagesWidget::MessagesWidget(QWidget *parent) : QWidget(parent) {
 
   // signals/slots
   QObject::connect(filter, &QLineEdit::textChanged, model, &MessageListModel::setFilterString);
-  QObject::connect(can, &CANMessages::streamStarted, this, &MessagesWidget::loadDBCFromFingerprint);
   QObject::connect(can, &CANMessages::updated, [this]() { model->updateState(); });
-  QObject::connect(dbc_combo, SIGNAL(activated(const QString &)), SLOT(loadDBCFromName(const QString &)));
-  QObject::connect(load_from_paste, &QPushButton::clicked, this, &MessagesWidget::loadDBCFromPaste);
-  QObject::connect(save_btn, &QPushButton::clicked, this, &MessagesWidget::saveDBC);
+  QObject::connect(dbc(), &DBCManager::DBCFileChanged, [this]() { model->updateState(true); });
   QObject::connect(table_widget->selectionModel(), &QItemSelectionModel::currentChanged, [=](const QModelIndex &current, const QModelIndex &previous) {
     if (current.isValid()) {
       emit msgSelectionChanged(current.data(Qt::UserRole).toString());
     }
   });
-
-  QFile json_file("./car_fingerprint_to_dbc.json");
-  if (json_file.open(QIODevice::ReadOnly)) {
-    fingerprint_to_dbc = QJsonDocument::fromJson(json_file.readAll());
-  }
-}
-
-void MessagesWidget::loadDBCFromName(const QString &name) {
-  if (name != dbc()->name()) {
-    dbc()->open(name);
-    dbc_combo->setCurrentText(name);
-    // re-sort model to refresh column 'Name'
-    model->updateState(true);
-  }
-}
-
-void MessagesWidget::loadDBCFromPaste() {
-  LoadDBCDialog dlg(this);
-  if (dlg.exec()) {
-    dbc()->open("from paste", dlg.dbc_edit->toPlainText());
-    dbc_combo->setCurrentText("loaded from paste");
-    model->updateState(true);
-  }
-}
-
-void MessagesWidget::loadDBCFromFingerprint() {
-  auto fingerprint = can->carFingerprint();
-  if (!fingerprint.isEmpty() && dbc()->name().isEmpty()) {
-    auto dbc_name = fingerprint_to_dbc[fingerprint];
-    if (dbc_name != QJsonValue::Undefined) {
-      loadDBCFromName(dbc_name.toString());
-    }
-  }
-}
-
-void MessagesWidget::saveDBC() {
-  SaveDBCDialog dlg(this);
-  dlg.dbc_edit->setText(dbc()->generateDBC());
-  dlg.exec();
 }
 
 // MessageListModel
@@ -235,60 +161,3 @@ void MessageListModel::sort(int column, Qt::SortOrder order) {
     updateState(true);
   }
 }
-
-// LoadDBCDialog
-
-LoadDBCDialog::LoadDBCDialog(QWidget *parent) : QDialog(parent) {
-  QVBoxLayout *main_layout = new QVBoxLayout(this);
-  dbc_edit = new QTextEdit(this);
-  dbc_edit->setAcceptRichText(false);
-  dbc_edit->setPlaceholderText(tr("paste DBC file here"));
-  main_layout->addWidget(dbc_edit);
-  auto buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
-  main_layout->addWidget(buttonBox);
-
-  setMinimumSize({640, 480});
-  QObject::connect(buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept);
-  QObject::connect(buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject);
-}
-
-// SaveDBCDialog
-
-SaveDBCDialog::SaveDBCDialog(QWidget *parent) : QDialog(parent) {
-  setWindowTitle(tr("Save DBC"));
-  QVBoxLayout *main_layout = new QVBoxLayout(this);
-  dbc_edit = new QTextEdit(this);
-  dbc_edit->setAcceptRichText(false);
-  main_layout->addWidget(dbc_edit);
-
-  QPushButton *copy_to_clipboard = new QPushButton(tr("Copy To Clipboard"), this);
-  QPushButton *save_as = new QPushButton(tr("Save As"), this);
-
-  QHBoxLayout *btn_layout = new QHBoxLayout();
-  btn_layout->addStretch();
-  btn_layout->addWidget(copy_to_clipboard);
-  btn_layout->addWidget(save_as);
-  main_layout->addLayout(btn_layout);
-  setMinimumSize({640, 480});
-
-  QObject::connect(copy_to_clipboard, &QPushButton::clicked, this, &SaveDBCDialog::copytoClipboard);
-  QObject::connect(save_as, &QPushButton::clicked, this, &SaveDBCDialog::saveAs);
-}
-
-void SaveDBCDialog::copytoClipboard() {
-  dbc_edit->selectAll();
-  dbc_edit->copy();
-  QDialog::accept();
-}
-
-void SaveDBCDialog::saveAs() {
-  QString file_name = QFileDialog::getSaveFileName(this, tr("Save File"),
-                                                   QDir::homePath() + "/untitled.dbc", tr("DBC (*.dbc)"));
-  if (!file_name.isEmpty()) {
-    QFile file(file_name);
-    if (file.open(QIODevice::WriteOnly)) {
-      file.write(dbc_edit->toPlainText().toUtf8());
-    }
-    QDialog::accept();
-  }
-}
diff --git a/tools/cabana/messageswidget.h b/tools/cabana/messageswidget.h
index 255dce7dc8..450c7003b7 100644
--- a/tools/cabana/messageswidget.h
+++ b/tools/cabana/messageswidget.h
@@ -1,32 +1,9 @@
 #pragma once
 
 #include <QAbstractTableModel>
-#include <QComboBox>
-#include <QDialog>
-#include <QJsonDocument>
 #include <QTableView>
-#include <QTextEdit>
 
 #include "tools/cabana/canmessages.h"
-
-class LoadDBCDialog : public QDialog {
-  Q_OBJECT
-
-public:
-  LoadDBCDialog(QWidget *parent);
-  QTextEdit *dbc_edit;
-};
-
-class SaveDBCDialog : public QDialog {
-  Q_OBJECT
-
-public:
-  SaveDBCDialog(QWidget *parent);
-  void copytoClipboard();
-  void saveAs();
-  QTextEdit *dbc_edit;
-};
-
 class MessageListModel : public QAbstractTableModel {
 Q_OBJECT
 
@@ -58,18 +35,10 @@ class MessagesWidget : public QWidget {
 public:
   MessagesWidget(QWidget *parent);
 
-public slots:
-  void loadDBCFromName(const QString &name);
-  void loadDBCFromFingerprint();
-  void loadDBCFromPaste();
-  void saveDBC();
-
 signals:
   void msgSelectionChanged(const QString &message_id);
 
 protected:
   QTableView *table_widget;
-  QComboBox *dbc_combo;
   MessageListModel *model;
-  QJsonDocument fingerprint_to_dbc;
 };