QDialogButtonBox: Don't set focus in a dialog with StrongFocus children

A QDialogButtonBox with the first accept button becoming default, didn't
explicitly set focus on such a button in a QDialog.
d44413d526ec12ed83acd7343c2005782178c7ad implemented this missing
functionality. It set focus to the automatic default button, unless the
QDialog had a focusWidget() set.

That has caused a regression, in cases where
- the QDialog has a QWidget child with a Qt::StrongFocus policy, and
- the QDialog is not yet visible, so focusWidget() returns nullptr.

Amend d44413d526ec12ed83acd7343c2005782178c7ad:

Implement a helper in QWidgetPrivate, that returns true, if a child
with a given focus policy is found.

Do not set focus to a QDialogButtonBox's automatic default button, when
- not located inside a QDialog, or
- a focusWidget() exists, or
- the dialog has QWidget child with Qt::StrongFocus, that is not a
child of the QDialogButtonBox.

Add an autotest function.

Pick-to: 6.7 6.6 6.5
Fixes: QTBUG-121514
Fixes: QTBUG-120049
Change-Id: I3c65ae36b56657f9af4a3a4b42f9b66e8bc5c534
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 37 insertions, 0 deletions

diff --git a/tests/auto/widgets/widgets/qdialogbuttonbox/tst_qdialogbuttonbox.cpp b/tests/auto/widgets/widgets/qdialogbuttonbox/tst_qdialogbuttonbox.cpp
index 65098f2fde..3e7dc92da1 100644
--- a/tests/auto/widgets/widgets/qdialogbuttonbox/tst_qdialogbuttonbox.cpp
+++ b/tests/auto/widgets/widgets/qdialogbuttonbox/tst_qdialogbuttonbox.cpp
@@ -6,6 +6,7 @@
 #include <QtWidgets/QStyle>
 #include <QtWidgets/QLayout>
 #include <QtWidgets/QDialog>
+#include <QtWidgets/QLineEdit>
 #include <QtGui/QAction>
 #include <QtGui/QStyleHints>
 #include <qdialogbuttonbox.h>
@@ -82,6 +83,8 @@ private slots:
     void task191642_default();
     void testDeletedStandardButton();
     void automaticDefaultButton();
+    void initialFocus_data();
+    void initialFocus();
 
 private:
     qint64 timeStamp;
@@ -958,5 +961,39 @@ void tst_QDialogButtonBox::automaticDefaultButton()
     }
 }
 
+void tst_QDialogButtonBox::initialFocus_data()
+{
+    QTest::addColumn<Qt::FocusPolicy>("focusPolicy");
+    QTest::addColumn<bool>("lineEditHasFocus");
+
+    QTest::addRow("TabFocus") << Qt::FocusPolicy::TabFocus << false;
+    QTest::addRow("StrongFocus") << Qt::FocusPolicy::StrongFocus << true;
+    QTest::addRow("NoFocus") << Qt::FocusPolicy::NoFocus << false;
+    QTest::addRow("ClickFocus") << Qt::FocusPolicy::ClickFocus << false;
+    QTest::addRow("WheelFocus") << Qt::FocusPolicy::WheelFocus << false;
+}
+
+void tst_QDialogButtonBox::initialFocus()
+{
+    QFETCH(const Qt::FocusPolicy, focusPolicy);
+    QFETCH(const bool, lineEditHasFocus);
+    QDialog dialog;
+    QVBoxLayout *layout = new QVBoxLayout(&dialog);
+    QLineEdit *lineEdit = new QLineEdit(&dialog);
+    lineEdit->setFocusPolicy(focusPolicy);
+    layout->addWidget(lineEdit);
+    QDialogButtonBox *dialogButtonBox = new QDialogButtonBox(&dialog);
+    layout->addWidget(dialogButtonBox);
+    dialogButtonBox->addButton(QDialogButtonBox::Reset);
+    const auto *firstAcceptButton = dialogButtonBox->addButton(QDialogButtonBox::Ok);
+    dialogButtonBox->addButton(QDialogButtonBox::Cancel);
+    dialog.show();
+    dialog.activateWindow();
+    if (lineEditHasFocus)
+        QTRY_VERIFY(lineEdit->hasFocus());
+    else
+        QTRY_VERIFY(firstAcceptButton->hasFocus());
+}
+
 QTEST_MAIN(tst_QDialogButtonBox)
 #include "tst_qdialogbuttonbox.moc"