cabana: use monospace font for hex string (#26102)

specify monospace font for hex string

tools/cabana/detailwidget.cc

@@ -1,6 +1,7 @@
 #include "tools/cabana/detailwidget.h"
 
 #include <QDialogButtonBox>
+#include <QFontDatabase>
 #include <QFormLayout>
 #include <QHeaderView>
 #include <QMessageBox>
@@ -179,7 +180,7 @@ void BinaryView::setMessage(const QString &message_id) {
       item->setFlags(item->flags() ^ Qt::ItemIsEditable);
       item->setTextAlignment(Qt::AlignCenter);
       if (j == 8) {
-        QFont font;
+        QFont font = QFontDatabase::systemFont(QFontDatabase::FixedFont);
         font.setBold(true);
         item->setFont(font);
         item->setFlags(item->flags() ^ Qt::ItemIsSelectable);

tools/cabana/historylog.cc

@@ -1,20 +1,25 @@
 #include "tools/cabana/historylog.h"
 
+#include <QFontDatabase>
 #include <QHeaderView>
 #include <QVBoxLayout>
 
 QVariant HistoryLogModel::data(const QModelIndex &index, int role) const {
+  auto msg = dbc()->msg(msg_id);
   if (role == Qt::DisplayRole) {
     const auto &can_msgs = can->messages(msg_id);
     if (index.row() < can_msgs.size()) {
       const auto &can_data = can_msgs[index.row()];
-      auto msg = dbc()->msg(msg_id);
       if (msg && index.column() < msg->sigs.size()) {
         return get_raw_value((uint8_t *)can_data.dat.begin(), can_data.dat.size(), msg->sigs[index.column()]);
       } else {
         return toHex(can_data.dat);
       }
     }
+  } else if (role == Qt::FontRole) {
+    if (index.column() == 0 && !(msg && msg->sigs.size() > 0)) {
+      return QFontDatabase::systemFont(QFontDatabase::FixedFont);
+    }
   }
   return {};
 }

tools/cabana/messageswidget.cc

@@ -2,6 +2,7 @@
 
 #include <QComboBox>
 #include <QCompleter>
+#include <QFontDatabase>
 #include <QHeaderView>
 #include <QLineEdit>
 #include <QPushButton>
@@ -107,6 +108,10 @@ QVariant MessageListModel::data(const QModelIndex &index, int role) const {
     }
   } else if (role == Qt::UserRole) {
     return std::next(can->can_msgs.begin(), index.row()).key();
+  } else if (role == Qt::FontRole) {
+    if (index.column() == 3) {
+      return QFontDatabase::systemFont(QFontDatabase::FixedFont);
+    }
   }
   return {};
 }