Core: Add ICore::dialogParent() specific for use as dialog parent

Change-Id: I72dca0f95b418a32ac3859f086053f91b9e9ec67
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

src/plugins/coreplugin/icore.cpp

@@ -33,6 +33,7 @@
 #include <extensionsystem/pluginmanager.h>
 
 #include <QSysInfo>
+#include <QApplication>
 
 /*!
     \namespace Core
@@ -170,9 +171,15 @@
 
     Returns the main application window.
 
-    For use as dialog parent, and so on.
+    For dialog parents use \c dialogParent().
 */
 
+/*!
+    \fn QWidget *ICore::dialogParent()
+
+    Returns a widget pointer suitable to use as parent for QDialogs.
+ */
+
 /*!
     \fn IContext *ICore::currentContextObject()
 
@@ -451,6 +458,12 @@ QWidget *ICore::mainWindow()
     return m_mainwindow;
 }
 
+QWidget *ICore::dialogParent()
+{
+    QWidget *active = QApplication::activeModalWidget();
+    return active ? active : m_mainwindow;
+}
+
 QStatusBar *ICore::statusBar()
 {
     return m_mainwindow->statusBar();

src/plugins/coreplugin/icore.h

@@ -94,6 +94,7 @@ public:
     static QString buildCompatibilityString();
 
     static QWidget *mainWindow();
+    static QWidget *dialogParent();
     static QStatusBar *statusBar();
     /* Raises and activates the window for the widget. This contains workarounds for X11. */
     static void raiseWindow(QWidget *widget);