cabana: fix button geometries (#27659)

old-commit-hash: 1a560a1a6c

tools/cabana/signaledit.cc

@@ -415,7 +415,7 @@ SignalView::SignalView(ChartsWidget *charts, QWidget *parent) : charts(charts),
   hl->addWidget(collapse_btn);
 
   // tree view
-  tree = new QTreeView(this);
+  tree = new TreeView(this);
   tree->setModel(model = new SignalModel(this));
   tree->setItemDelegate(new SignalItemDelegate(this));
   tree->setFrameShape(QFrame::NoFrame);
@@ -439,7 +439,6 @@ SignalView::SignalView(ChartsWidget *charts, QWidget *parent) : charts(charts),
   QObject::connect(tree, &QTreeView::viewportEntered, [this]() { emit highlight(nullptr); });
   QObject::connect(tree, &QTreeView::entered, [this](const QModelIndex &index) { emit highlight(model->getItem(index)->sig); });
   QObject::connect(model, &QAbstractItemModel::modelReset, this, &SignalView::rowsChanged);
-  QObject::connect(model, &QAbstractItemModel::rowsInserted, this, &SignalView::rowsChanged);
   QObject::connect(model, &QAbstractItemModel::rowsRemoved, this, &SignalView::rowsChanged);
   QObject::connect(dbc(), &DBCManager::signalAdded, [this](MessageId id, const cabana::Signal *sig) { selectSignal(sig); });
 

tools/cabana/signaledit.h

@@ -108,8 +108,17 @@ private:
   void rowsChanged();
   void leaveEvent(QEvent *event);
 
+  struct TreeView : public QTreeView {
+    TreeView(QWidget *parent) : QTreeView(parent) {}
+    void rowsInserted(const QModelIndex &parent, int start, int end) override {
+      ((SignalView *)parentWidget())->rowsChanged();
+      // update widget geometries in QTreeView::rowsInserted
+      QTreeView::rowsInserted(parent, start, end);
+    }
+  };
+
   MessageId msg_id;
-  QTreeView *tree;
+  TreeView *tree;
   QLineEdit *filter_edit;
   ChartsWidget *charts;
   QLabel *signal_count_lb;