1 files changed, 6 insertions, 1 deletions
diff --git a/Swift/QtUI/Trellis/QtDynamicGridLayout.cpp b/Swift/QtUI/Trellis/QtDynamicGridLayout.cpp
index 5600cc8..b753ffa 100644
--- a/Swift/QtUI/Trellis/QtDynamicGridLayout.cpp
+++ b/Swift/QtUI/Trellis/QtDynamicGridLayout.cpp
@@ -263,61 +263,66 @@ void QtDynamicGridLayout::setDimensions(const QSize& dim) {
     int oldHeight = oldLayout->rowCount();
     int maxCol = qMax(oldWidth, dim.width());
     int minCol = qMin(oldWidth, dim.width());
     int maxRow = qMax(oldHeight, dim.height());
     int minRow = qMin(oldHeight, dim.height());
 
     for (int row = 0; row < maxRow; row++) {
         for (int col = 0; col < maxCol; col++) {
             QLayoutItem* oldItem = oldLayout->itemAtPosition(row, col);
             QLayoutItem* newItem = newLayout->itemAtPosition(row, col);
             bool removeRow = !(row < dim.height());
             bool removeCol = !(col < dim.width());
 
             if (removeCol || removeRow) {
                 if (oldItem) {
                     int squeezeRow = removeRow ? (minRow - 1) : row;
                     int squeezeCol = removeCol ? (minCol - 1) : col;
                     newItem = newLayout->itemAtPosition(squeezeRow, squeezeCol);
                     if (!newItem) {
                         newLayout->addWidget(createDNDTabWidget(this), squeezeRow, squeezeCol);
                         newItem = newLayout->itemAtPosition(squeezeRow, squeezeCol);
                     }
                     QtTabWidget* oldTabWidget = dynamic_cast<QtTabWidget*>(oldItem->widget());
                     QtTabWidget* newTabWidget = dynamic_cast<QtTabWidget*>(newItem->widget());
                     assert(oldTabWidget && newTabWidget);
 
                     oldTabWidget->hide();
                     while(oldTabWidget->count()) {
                         QIcon icon = oldTabWidget->tabIcon(0);
                         QString text = oldTabWidget->tabText(0);
-                        newTabWidget->addTab(oldTabWidget->widget(0), icon, text);
+                        QWidget* movingTab = oldTabWidget->widget(0);
+                        //If handling was allowed, QtChatTabs::handleWidgetShown() would be triggered when newTabWidget has no tabs.
+                        //That would access indices of the gridLayout_ that are null because they have been migrated to the newLayout.
+                        movingTab->blockSignals(true);
+                        newTabWidget->addTab(movingTab, icon, text);
+                        movingTab->blockSignals(false);
                     }
                     delete oldTabWidget;
                 }
             } else {
                 if (oldItem) {
                     newLayout->addWidget(oldItem->widget(), row, col);
                     newItem = newLayout->itemAtPosition(row, col);
                 } else {
                     newLayout->addWidget(createDNDTabWidget(this), row, col);
                 }
             }
         }
     }
 
     for (int col = 0; col < dim.width(); col++) {
         newLayout->setColumnStretch(col, 1);
     }
     for (int row = 0; row < dim.height(); row++) {
         newLayout->setRowStretch(row, 1);
     }
 
     setUpdatesEnabled(true);
     delete layout();
     setLayout(newLayout);
     gridLayout_ = newLayout;
 
     resizing_ = false;
     setCurrentWidget(restoredWidget);
 
     updateEmphasiseFocusOnTabs();