fix: delay connect native state change signal

Change-Id: I0ed487799fb233db476f97a6036a315732a2ad1d

src/widgets/dthememanager.cpp

@@ -231,6 +231,7 @@ class DThemeManagerPrivate : public DCORE_NAMESPACE::DObjectPrivate
     void registerWidget(QWidget *widget, const QString &filename, const QStringList &propertys)
     {
         if (filename.isEmpty()) {
+            qWarning() << "can not load qss with out filename" << widget;
             return;
         }
 

src/widgets/dtitlebar.cpp

@@ -66,6 +66,7 @@ class DTitlebarPrivate : public DTK_CORE_NAMESPACE::DObjectPrivate
     void updateButtonsState(Qt::WindowFlags type);
     void updateButtonsFunc();
     void handleParentWindowStateChange();
+    void handleParentWindowIdChange();
     void _q_toggleWindowState();
     void _q_showMinimized();
     void _q_onTopWindowMotifHintsChanged(quint32 winId);
@@ -216,12 +217,9 @@ void DTitlebarPrivate::init()
     q->connect(DWindowManagerHelper::instance(), SIGNAL(windowMotifWMHintsChanged(quint32)),
                q, SLOT(_q_onTopWindowMotifHintsChanged(quint32)));
 
-    if (targetWindow()) {
-        q->connect(targetWindow()->windowHandle(), &QWindow::windowStateChanged,
-        q, [ = ](Qt::WindowState) {
-            handleParentWindowStateChange();
-        });
-    }
+    // connect state change if parent has native window
+    // or connect when parent winid change
+    handleParentWindowIdChange();
 }
 
 QWidget *DTitlebarPrivate::targetWindow()
@@ -341,6 +339,22 @@ void DTitlebarPrivate::handleParentWindowStateChange()
     updateButtonsState(targetWindow()->windowFlags());
 }
 
+//!
+//! \brief DTitlebarPrivate::handleParentWindowIdChange
+//! Them WindowStateChnage Event will miss some state changed message,
+//! So use windowHandle::windowStateChanged instead
+void DTitlebarPrivate::handleParentWindowIdChange()
+{
+    D_Q(DTitlebar);
+    if (targetWindow()->windowHandle()) {
+        q->disconnect(targetWindow()->windowHandle(), &QWindow::windowStateChanged, q, Q_NULLPTR);
+        q->connect(targetWindow()->windowHandle(), &QWindow::windowStateChanged,
+        q, [ = ](Qt::WindowState) {
+            handleParentWindowStateChange();
+        });
+    }
+}
+
 void DTitlebarPrivate::_q_toggleWindowState()
 {
     QWidget *parentWindow = targetWindow();
@@ -623,8 +637,8 @@ bool DTitlebar::eventFilter(QObject *obj, QEvent *event)
 
         switch (event->type()) {
         // !!! NO state change when fullscreen state change to nostate ?
-        case QEvent::WindowStateChange: {
-            d->handleParentWindowStateChange();
+        case QEvent::WinIdChange: {
+            d->handleParentWindowIdChange();
             break;
         }
         case QEvent::ShowToParent: