Return focus to correct widget after showing menu

By the time we call setKeyboardMode(true), the menu may
already have taken focus. This change sets keyboardFocusWidget
before opening the popup, and makes sure that keyboardFocusWidget
is not set to the popup. (We cannot remove the assignment from
setKeyboardMode(), since it's called from several places.)

[ChangeLog][QtWidgets] Fixed widget losing focus after showing
menu second time.

Task-number: QTBUG-56860
Change-Id: Ic01726bf694e6f365dd7b601ad555156e0fdf6c5
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 48 insertions, 0 deletions

diff --git a/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp b/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp
index 9a0ca0565e..251a351cc1 100644
--- a/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp
+++ b/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp
@@ -39,6 +39,7 @@
 #include <qstyleoption.h>
 #include <QVBoxLayout>
 #include <QLabel>
+#include <QPlainTextEdit>
 #include <qscreen.h>
 
 #include <qobject.h>
@@ -106,6 +107,7 @@ private slots:
     void allowActiveAndDisabled();
 #endif
 
+    void taskQTBUG56860_focus();
     void check_endKey();
     void check_homeKey();
 
@@ -710,6 +712,52 @@ void tst_QMenuBar::check_cursorKeys3()
 }
 #endif
 
+void tst_QMenuBar::taskQTBUG56860_focus()
+{
+#if defined(Q_OS_DARWIN)
+    QSKIP("Native key events are needed to test menu action activation on macOS.");
+#endif
+    QMainWindow w;
+    QMenuBar *mb = w.menuBar();
+
+    if (mb->platformMenuBar())
+        QSKIP("This test requires the Qt menubar.");
+
+    QMenu *em = mb->addMenu("&Edit");
+    em->setObjectName("EditMenu");
+    em->addAction("&Cut");
+    em->addAction("C&opy");
+    QPlainTextEdit *e = new QPlainTextEdit;
+    e->setObjectName("edit");
+
+    w.setCentralWidget(e);
+    w.show();
+    QApplication::setActiveWindow(&w);
+    QVERIFY(QTest::qWaitForWindowActive(&w));
+
+    QTRY_COMPARE(QApplication::focusWidget(), e);
+
+    // Open menu
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_E, Qt::AltModifier );
+    QTRY_COMPARE(QApplication::activePopupWidget(), em);
+    // key down to trigger focus
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_Down );
+    // and press ENTER to close
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_Enter );
+    QTRY_COMPARE(QApplication::activePopupWidget(), nullptr);
+    // focus should have returned to the editor by now
+    QTRY_COMPARE(QApplication::focusWidget(), e);
+
+    // Now do it all over again...
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_E, Qt::AltModifier );
+    QTRY_COMPARE(QApplication::activePopupWidget(), em);
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_Down );
+    QTest::keyClick(static_cast<QWidget *>(0), Qt::Key_Enter );
+    QTRY_COMPARE(QApplication::activePopupWidget(), nullptr);
+    QTRY_COMPARE(QApplication::focusWidget(), e);
+
+}
+
 /*!
     If a popupmenu is active you can use home to go quickly to the first item in the menu.
 */