QWidget: fix setTabOrder for compound widgets

81e298a51d08c510457b4a26b37c0d4aac5eba65 fixed a case where the focus
chain was screwed up when the order was already correct. This worked
correctly in most cases but not when the next focus widget of the first
one had Qt::NoFocus.
The optimization check if lastFocusChildOfFirst is the same as second is
thrown away since it now does not longer screw up the focus chain and
the save would only be four pointer assignments.

Fixes: QTBUG-75388
Task-number: QTBUG-10907
Task-number: QTBUG-68393
Task-number: QTBUG-69619
Change-Id: I581ed532156c34ea970123afd063194aab016304
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
 
 
 
 

1 files changed, 73 insertions, 0 deletions

diff --git a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
index c0dfaf80a3..489edb703c 100644
--- a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
+++ b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
@@ -180,6 +180,7 @@ private slots:
     void tabOrderWithProxy();
     void tabOrderWithCompoundWidgets();
     void tabOrderNoChange();
+    void tabOrderNoChange2();
 #if defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
     void activation();
 #endif
@@ -1940,6 +1941,24 @@ static QVector<QWidget*> getFocusChain(QWidget *start, bool bForward)
     return ret;
 }
 
+//#define DEBUG_FOCUS_CHAIN
+static void dumpFocusChain(QWidget *start, bool bForward, const char *desc = nullptr)
+{
+#ifdef DEBUG_FOCUS_CHAIN
+    qDebug() << "Dump focus chain, start:" << start << "isForward:" << bForward << desc;
+    QWidget *cur = start;
+    do {
+        qDebug() << cur;
+        auto widgetPrivate = static_cast<QWidgetPrivate *>(qt_widget_private(cur));
+        cur = bForward ? widgetPrivate->focus_next : widgetPrivate->focus_prev;
+    } while (cur != start);
+#else
+    Q_UNUSED(start)
+    Q_UNUSED(bForward)
+    Q_UNUSED(desc)
+#endif
+}
+
 void tst_QWidget::tabOrderNoChange()
 {
     QWidget w;
@@ -1951,7 +1970,61 @@ void tst_QWidget::tabOrderNoChange()
 
     const auto focusChainForward = getFocusChain(&w, true);
     const auto focusChainBackward = getFocusChain(&w, false);
+    dumpFocusChain(&w, true);
     QWidget::setTabOrder(tabWidget, tv);
+    dumpFocusChain(&w, true);
+    QCOMPARE(focusChainForward, getFocusChain(&w, true));
+    QCOMPARE(focusChainBackward, getFocusChain(&w, false));
+}
+
+void tst_QWidget::tabOrderNoChange2()
+{
+    QWidget w;
+    auto *verticalLayout = new QVBoxLayout(&w);
+    auto *tabWidget = new QTabWidget(&w);
+    tabWidget->setObjectName("tabWidget");
+    verticalLayout->addWidget(tabWidget);
+
+    auto *tab1 = new QWidget(tabWidget);
+    tab1->setObjectName("tab1");
+    auto *vLay1 = new QVBoxLayout(tab1);
+    auto *le1 = new QLineEdit(tab1);
+    le1->setObjectName("le1");
+    auto *le2 = new QLineEdit(tab1);
+    le2->setObjectName("le2");
+    vLay1->addWidget(le1);
+    vLay1->addWidget(le2);
+    tabWidget->addTab(tab1, QStringLiteral("Tab 1"));
+
+    auto *tab2 = new QWidget(tabWidget);
+    tab2->setObjectName("tab2");
+    auto *vLay2 = new QVBoxLayout(tab2);
+    auto *le3 = new QLineEdit(tab2);
+    le3->setObjectName("le3");
+    auto *le4 = new QLineEdit(tab2);
+    le4->setObjectName("le4");
+    vLay2->addWidget(le3);
+    vLay2->addWidget(le4);
+    tabWidget->addTab(tab2, QStringLiteral("Tab 2"));
+
+    const auto focusChainForward = getFocusChain(&w, true);
+    const auto focusChainBackward = getFocusChain(&w, false);
+    dumpFocusChain(&w, true);
+    dumpFocusChain(&w, false);
+    // this will screw up the focus chain order without visible changes,
+    // so don't call it here for the simplicity of the test
+    //QWidget::setTabOrder(tabWidget, le1);
+
+    QWidget::setTabOrder(le1, le2);
+    dumpFocusChain(&w, true, "QWidget::setTabOrder(le1, le2)");
+    QWidget::setTabOrder(le2, le3);
+    dumpFocusChain(&w, true, "QWidget::setTabOrder(le2, le3)");
+    QWidget::setTabOrder(le3, le4);
+    dumpFocusChain(&w, true, "QWidget::setTabOrder(le3, le4)");
+    QWidget::setTabOrder(le4, tabWidget);
+    dumpFocusChain(&w, true, "QWidget::setTabOrder(le4, tabWidget)");
+    dumpFocusChain(&w, false);
+
     QCOMPARE(focusChainForward, getFocusChain(&w, true));
     QCOMPARE(focusChainBackward, getFocusChain(&w, false));
 }