Added QWindow::setTransientParent().

Make the transient parent relationship explicit instead of having it
encoded through the window flags.

5 files changed, 63 insertions, 18 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index b5bcc72d10..e53a205e88 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -105,7 +105,7 @@ void QWindow::create()
             QObject *object = childObjects.at(i);
             if(object->isWindowType()) {
                 QWindow *window = static_cast<QWindow *>(object);
-                if (window->d_func()->platformWindow && !window->isTopLevel())
+                if (window->d_func()->platformWindow)
                     window->d_func()->platformWindow->setParent(d->platformWindow);
             }
         }
@@ -138,7 +138,7 @@ void QWindow::setParent(QWindow *parent)
     QObject::setParent(parent);
 
     if (d->platformWindow) {
-        if (parent && parent->d_func()->platformWindow && !isTopLevel()) {
+        if (parent && parent->d_func()->platformWindow) {
             d->platformWindow->setParent(parent->d_func()->platformWindow);
         } else {
             d->platformWindow->setParent(0);
@@ -149,12 +149,12 @@ void QWindow::setParent(QWindow *parent)
 }
 
 /*!
-   Returns whether the window is top level.
+   Returns whether the window is top level, i.e. has no parent window.
  */
 bool QWindow::isTopLevel() const
 {
     Q_D(const QWindow);
-    return d->windowFlags & Qt::Window;
+    return d->parentWindow != 0;
 }
 
 bool QWindow::isModal() const
@@ -293,6 +293,21 @@ void QWindow::setWindowState(Qt::WindowState state)
         d->windowState = state;
 }
 
+/*!
+  Sets the transient parent, which is a hint to the window manager that this window is a dialog or pop-up on behalf of the given window.
+*/
+void QWindow::setTransientParent(QWindow *parent)
+{
+    Q_D(QWindow);
+    d->transientParent = parent;
+}
+
+QWindow *QWindow::transientParent() const
+{
+    Q_D(const QWindow);
+    return d->transientParent.data();
+}
+
 QSize QWindow::minimumSize() const
 {
     Q_D(const QWindow);
diff --git a/src/gui/kernel/qwindow.h b/src/gui/kernel/qwindow.h
index 998a48fb42..5b002a4791 100644
--- a/src/gui/kernel/qwindow.h
+++ b/src/gui/kernel/qwindow.h
@@ -119,6 +119,9 @@ public:
     Qt::WindowState windowState() const;
     void setWindowState(Qt::WindowState state);
 
+    void setTransientParent(QWindow *parent);
+    QWindow *transientParent() const;
+
     QSize minimumSize() const;
     QSize maximumSize() const;
     QSize baseSize() const;
diff --git a/src/gui/kernel/qwindow_p.h b/src/gui/kernel/qwindow_p.h
index f52dd559f1..aca26089ce 100644
--- a/src/gui/kernel/qwindow_p.h
+++ b/src/gui/kernel/qwindow_p.h
@@ -68,6 +68,7 @@ public:
         , surface(0)
         , windowState(Qt::WindowNoState)
         , maximumSize(QWINDOWSIZE_MAX, QWINDOWSIZE_MAX)
+        , transientParent(0)
     {
         isWindow = true;
     }
@@ -94,6 +95,7 @@ public:
     QSize sizeIncrement;
 
     Qt::WindowModality modality;
+    QPointer<QWindow> transientParent;
 };
 
 
diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 2a7594ee9b..0f1375d764 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -136,7 +136,7 @@ void QXcbWindow::create()
     QRect rect = window()->geometry();
 
     xcb_window_t xcb_parent_id = m_screen->root();
-    if (parent() && !window()->isTopLevel())
+    if (parent())
         xcb_parent_id = static_cast<QXcbWindow *>(parent())->xcb_window();
 
 #if defined(XCB_USE_GLX) || defined(XCB_USE_EGL)
@@ -322,14 +322,17 @@ void QXcbWindow::show()
         propagateSizeHints();
 
         // update WM_TRANSIENT_FOR
-        if (isTransient(window()) && parent()) {
-            // ICCCM 4.1.2.6
-            xcb_window_t parentWindow = static_cast<QXcbWindow *>(parent())->xcb_window();
-
-            // todo: set transient for group (wm_client_leader) if no parent, a la qwidget_x11.cpp
-            Q_XCB_CALL(xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, m_window,
-                                           XCB_ATOM_WM_TRANSIENT_FOR, XCB_ATOM_WINDOW, 32,
-                                           1, &parentWindow));
+        if (window()->transientParent() && isTransient(window())) {
+            QXcbWindow *transientXcbParent = static_cast<QXcbWindow *>(window()->transientParent()->handle());
+            if (transientXcbParent) {
+                // ICCCM 4.1.2.6
+                xcb_window_t parentWindow = transientXcbParent->xcb_window();
+
+                // todo: set transient for group (wm_client_leader) if no parent, a la qwidget_x11.cpp
+                Q_XCB_CALL(xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE, m_window,
+                                               XCB_ATOM_WM_TRANSIENT_FOR, XCB_ATOM_WINDOW, 32,
+                                               1, &parentWindow));
+            }
         }
 
         // update _MOTIF_WM_HINTS
diff --git a/src/widgets/kernel/qwidget_qpa.cpp b/src/widgets/kernel/qwidget_qpa.cpp
index 02487679bf..b4ed00d36d 100644
--- a/src/widgets/kernel/qwidget_qpa.cpp
+++ b/src/widgets/kernel/qwidget_qpa.cpp
@@ -65,8 +65,12 @@ void q_createNativeChildrenAndSetParent(QWindow *parentWindow, const QWidget *pa
                 if (childWidget->testAttribute(Qt::WA_NativeWindow)) {
                     if (!childWidget->windowHandle())
                         childWidget->winId();
-                    if (childWidget->windowHandle())
-                        childWidget->windowHandle()->setParent(parentWindow);
+                    if (childWidget->windowHandle()) {
+                        if (childWidget->isTopLevel())
+                            childWidget->windowHandle()->setTransientParent(parentWindow);
+                        else
+                            childWidget->windowHandle()->setParent(parentWindow);
+                    }
                 } else {
                     q_createNativeChildrenAndSetParent(parentWindow,childWidget);
                 }
@@ -103,8 +107,15 @@ void QWidgetPrivate::create_sys(WId window, bool initializeWindow, bool destroyO
     }
 
     if (QWidget *nativeParent = q->nativeParentWidget()) {
-        if (nativeParent->windowHandle())
-            win->setParent(nativeParent->windowHandle());
+        if (nativeParent->windowHandle()) {
+            if (flags & Qt::Window) {
+                win->setTransientParent(nativeParent->windowHandle());
+                win->setParent(0);
+            } else {
+                win->setTransientParent(0);
+                win->setParent(nativeParent->windowHandle());
+            }
+        }
     }
 
     win->create();
@@ -185,7 +196,18 @@ void QWidgetPrivate::setParent_sys(QWidget *newparent, Qt::WindowFlags f)
             q->windowHandle()->setWindowFlags(f);
             QWidget *parentWithWindow =
                 newparent ? (newparent->windowHandle() ? newparent : newparent->nativeParentWidget()) : 0;
-            q->windowHandle()->setParent(parentWithWindow ? parentWithWindow->windowHandle() : 0);
+            if (parentWithWindow) {
+                if (f & Qt::Window) {
+                    q->windowHandle()->setTransientParent(parentWithWindow->windowHandle());
+                    q->windowHandle()->setParent(0);
+                } else {
+                    q->windowHandle()->setTransientParent(0);
+                    q->windowHandle()->setParent(parentWithWindow->windowHandle());
+                }
+            } else {
+                q->windowHandle()->setTransientParent(0);
+                q->windowHandle()->setParent(0);
+            }
         }
     }