iOS: let QIOSScreen start/stop listening for device orientation

From the qpa docs, we only need to listen for device orientation
if orientationUpdateMask is non-zero

Change-Id: Id5e828cdff9a08794c8a029e11763cc037e1b959
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>

src/plugins/platforms/ios/qiosscreen.h

@@ -45,6 +45,7 @@
 #include <UIKit/UIKit.h>
 
 #include <qpa/qplatformscreen.h>
+#include <qiosorientationlistener.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -52,6 +53,7 @@ class QIOSScreen : public QPlatformScreen
 {
 public:
     QIOSScreen(unsigned int screenIndex);
+    ~QIOSScreen();
 
     enum ScreenIndex { MainScreen = 0 };
 
@@ -61,6 +63,10 @@ public:
     QImage::Format format() const;
     QSizeF physicalSize() const;
 
+    Qt::ScreenOrientation nativeOrientation() const;
+    Qt::ScreenOrientation orientation() const;
+    void setOrientationUpdateMask(Qt::ScreenOrientations mask);
+
     UIScreen *uiScreen() const;
 
 private:
@@ -68,6 +74,7 @@ private:
     QRect m_geometry;
     int m_depth;
     QSizeF m_physicalSize;
+    QIOSOrientationListener *m_orientationListener;
 };
 
 QT_END_NAMESPACE

src/plugins/platforms/ios/qiosscreen.mm

@@ -41,6 +41,7 @@
 
 #include "qiosscreen.h"
 #include "qioswindow.h"
+#include <qpa/qwindowsysteminterface.h>
 
 #include <sys/sysctl.h>
 
@@ -68,6 +69,7 @@ static QString deviceModelIdentifier()
 QIOSScreen::QIOSScreen(unsigned int screenIndex)
     : QPlatformScreen()
     , m_uiScreen([[UIScreen screens] objectAtIndex:qMin(screenIndex, [[UIScreen screens] count] - 1)])
+    , m_orientationListener(0)
 {
     NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
 
@@ -97,6 +99,11 @@ QIOSScreen::QIOSScreen(unsigned int screenIndex)
     [pool release];
 }
 
+QIOSScreen::~QIOSScreen()
+{
+    [m_orientationListener release];
+}
+
 QRect QIOSScreen::geometry() const
 {
     return m_geometry;
@@ -123,6 +130,26 @@ QSizeF QIOSScreen::physicalSize() const
     return m_physicalSize;
 }
 
+Qt::ScreenOrientation QIOSScreen::nativeOrientation() const
+{
+    return Qt::PortraitOrientation;
+}
+
+Qt::ScreenOrientation QIOSScreen::orientation() const
+{
+    return m_orientationListener ? m_orientationListener->m_orientation : nativeOrientation();
+}
+
+void QIOSScreen::setOrientationUpdateMask(Qt::ScreenOrientations mask)
+{
+    if (m_orientationListener && mask == Qt::PrimaryOrientation) {
+        [m_orientationListener release];
+        m_orientationListener = 0;
+    } else if (!m_orientationListener) {
+        m_orientationListener = [[QIOSOrientationListener alloc] initWithQIOSScreen:this];
+    }
+}
+
 UIScreen *QIOSScreen::uiScreen() const
 {
     return m_uiScreen;