From 3f60bd305ad3b094356750c21e253704bbe62681 Mon Sep 17 00:00:00 2001
From: Friedemann Kleint <Friedemann.Kleint@digia.com>
Date: Fri, 4 Jul 2014 10:39:19 +0200
Subject: Add convenience function for checking screen changes to
 QPlatformWindow.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Add function returning the screen for a new geometry for geometry
change events. This ensures that the checking is done in platform
screen coordinates (which might differ from QScreen coordinates
due to high-DPI changes) and also that no screen changes are
emitted for child windows.

Change-Id: I406750f59f006f834c386d09c0c85a804014924a
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
---
 src/gui/kernel/qplatformwindow.cpp | 23 +++++++++++++++++++++++
 src/gui/kernel/qplatformwindow.h   |  1 +
 2 files changed, 24 insertions(+)

(limited to 'src/gui')

diff --git a/src/gui/kernel/qplatformwindow.cpp b/src/gui/kernel/qplatformwindow.cpp
index faaf418522..bb7b690992 100644
--- a/src/gui/kernel/qplatformwindow.cpp
+++ b/src/gui/kernel/qplatformwindow.cpp
@@ -473,6 +473,29 @@ QString QPlatformWindow::formatWindowTitle(const QString &title, const QString &
     return fullTitle;
 }
 
+/*!
+    Helper function for finding the new screen for \a newGeometry in response to
+    a geometry changed event. Returns the new screen if the window was moved to
+    another virtual sibling. If the screen changes, the platform plugin should call
+    QWindowSystemInterface::handleWindowScreenChanged().
+    \note: The current screen will always be returned for child windows since
+    they should never signal screen changes.
+
+    \since 5.4
+    \sa QWindowSystemInterface::handleWindowScreenChanged()
+*/
+QPlatformScreen *QPlatformWindow::screenForGeometry(const QRect &newGeometry) const
+{
+    QPlatformScreen *currentScreen = screen();
+    if (!parent() && !currentScreen->geometry().intersects(newGeometry)) {
+        Q_FOREACH (QPlatformScreen* screen, currentScreen->virtualSiblings()) {
+            if (screen->geometry().intersects(newGeometry))
+                return screen;
+        }
+    }
+    return currentScreen;
+}
+
 /*!
     Reimplement this method to set whether the window demands attention
     (for example, by flashing the taskbar icon) depending on \a enabled.
diff --git a/src/gui/kernel/qplatformwindow.h b/src/gui/kernel/qplatformwindow.h
index 39bd8324a0..8f0e5ff352 100644
--- a/src/gui/kernel/qplatformwindow.h
+++ b/src/gui/kernel/qplatformwindow.h
@@ -139,6 +139,7 @@ public:
 
 protected:
     static QString formatWindowTitle(const QString &title, const QString &separator);
+    QPlatformScreen *screenForGeometry(const QRect &newGeometry) const;
 
     QScopedPointer<QPlatformWindowPrivate> d_ptr;
 private:
-- 
cgit v1.2.3