Block input to a window shown while an application modal dialog is visible

Although the window is refused input for the most part from the system,
it does not act like that it is blocked by the application modal dialog.
This ensures that it is the case and prevents things like being able to
double click on the title bar to maximize the window on Windows.

Task-number: QTBUG-49102
Change-Id: If1582819b90cb2ec9d891f664da24f13bfec7103
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

2 files changed, 44 insertions, 0 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index cf4a75dfce..eb9d7a8868 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -576,6 +576,8 @@ void QWindow::setVisible(bool visible)
             QGuiApplicationPrivate::showModalWindow(this);
         else
             QGuiApplicationPrivate::hideModalWindow(this);
+    } else if (visible && QGuiApplication::modalWindow()) {
+        QGuiApplicationPrivate::updateBlockedStatus(this);
     }
 
 #ifndef QT_NO_CURSOR
diff --git a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
index 92f7182249..e1366ce2eb 100644
--- a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
+++ b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
@@ -105,6 +105,7 @@ private slots:
     void stateChange();
     void flags();
     void cleanup();
+    void testBlockingWindowShownAfterModalDialog();
 
 private:
     QPoint m_availableTopLeft;
@@ -2241,6 +2242,47 @@ void tst_QWindow::flags()
     QCOMPARE(window.flags(), baseFlags | Qt::WindowStaysOnTopHint);
 }
 
+class EventWindow : public QWindow
+{
+public:
+    EventWindow() : QWindow(), gotBlocked(false) {}
+    bool gotBlocked;
+protected:
+    bool event(QEvent *e)
+    {
+        if (e->type() == QEvent::WindowBlocked)
+            gotBlocked = true;
+        return QWindow::event(e);
+    }
+};
+
+void tst_QWindow::testBlockingWindowShownAfterModalDialog()
+{
+    EventWindow normalWindow;
+    normalWindow.setFramePosition(m_availableTopLeft + QPoint(80, 80));
+    normalWindow.resize(m_testWindowSize);
+    normalWindow.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&normalWindow));
+    QVERIFY(!normalWindow.gotBlocked);
+
+    QWindow dialog;
+    dialog.setFramePosition(m_availableTopLeft + QPoint(200, 200));
+    dialog.resize(m_testWindowSize);
+    dialog.setModality(Qt::ApplicationModal);
+    dialog.setFlags(Qt::Dialog);
+    dialog.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&dialog));
+    QVERIFY(normalWindow.gotBlocked);
+
+    EventWindow normalWindowAfter;
+    normalWindowAfter.setFramePosition(m_availableTopLeft + QPoint(80, 80));
+    normalWindowAfter.resize(m_testWindowSize);
+    QVERIFY(!normalWindowAfter.gotBlocked);
+    normalWindowAfter.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&normalWindowAfter));
+    QVERIFY(normalWindowAfter.gotBlocked);
+}
+
 #include <tst_qwindow.moc>
 QTEST_MAIN(tst_QWindow)