TabBar: fix mixing of fixed and implicitly resized tabs

Don't calculate the implicit item width based on the total width of
the whole control, but based on the available width that is left after
subtracting the items that have an explicit width and won't be resized.

Change-Id: Iae18dd9c9756b6f2afa143baab7d2501ce9d4697
Task-number: QTBUG-56265
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 17 insertions, 5 deletions

diff --git a/src/quicktemplates2/qquicktabbar.cpp b/src/quicktemplates2/qquicktabbar.cpp
index 6fe734bb..bf6c4e74 100644
--- a/src/quicktemplates2/qquicktabbar.cpp
+++ b/src/quicktemplates2/qquicktabbar.cpp
@@ -113,16 +113,28 @@ void QQuickTabBarPrivate::updateLayout()
     Q_Q(QQuickTabBar);
     const int count = contentModel->count();
     if (count > 0 && contentItem) {
-        const qreal itemWidth = (contentItem->width() - qMax(0, count - 1) * spacing) / count;
+        qreal reservedWidth = 0;
+        QVector<QQuickItem *> resizableItems;
+        resizableItems.reserve(count);
 
         for (int i = 0; i < count; ++i) {
             QQuickItem *item = q->itemAt(i);
             if (item) {
                 QQuickItemPrivate *p = QQuickItemPrivate::get(item);
-                if (!p->widthValid) {
-                    item->setWidth(itemWidth);
-                    p->widthValid = false;
-                }
+                if (!p->widthValid)
+                    resizableItems += item;
+                else
+                    reservedWidth += item->width();
+            }
+        }
+
+        if (!resizableItems.isEmpty()) {
+            const qreal totalSpacing = qMax(0, count - 1) * spacing;
+            const qreal itemWidth = (contentItem->width() - reservedWidth - totalSpacing) / resizableItems.count();
+
+            for (QQuickItem *item : qAsConst(resizableItems)) {
+                item->setWidth(itemWidth);
+                QQuickItemPrivate::get(item)->widthValid = false;
             }
         }
     }