diff --git a/src/core/UBDisplayManager.cpp b/src/core/UBDisplayManager.cpp
index 5aacc83a..59e858af 100644
--- a/src/core/UBDisplayManager.cpp
+++ b/src/core/UBDisplayManager.cpp
@@ -41,6 +41,8 @@
 
 #include "core/memcheck.h"
 
+#include "qdesktopwidget.h"
+
 UBDisplayManager::UBDisplayManager(QObject *parent)
     : QObject(parent)
     , mControlScreenIndex(-1)
@@ -55,8 +57,8 @@ UBDisplayManager::UBDisplayManager(QObject *parent)
 
     initScreenIndexes();
 
-    connect(mDesktop, SIGNAL(resized(int)), this, SLOT(adjustScreens(int)));
-    connect(mDesktop, SIGNAL(workAreaResized(int)), this, SLOT(adjustScreens(int)));
+    connect(mDesktop, &QDesktopWidget::resized, this, &UBDisplayManager::adjustScreens);
+    connect(mDesktop, &QDesktopWidget::workAreaResized, this, &UBDisplayManager::adjustScreens);
 }
 
 
diff --git a/src/core/UBDisplayManager.h b/src/core/UBDisplayManager.h
index e45044ca..a305716e 100644
--- a/src/core/UBDisplayManager.h
+++ b/src/core/UBDisplayManager.h
@@ -32,6 +32,7 @@
 
 class UBBlackoutWidget;
 class UBBoardView;
+class QDesktopWidget;
 
 class UBDisplayManager : public QObject
 {
diff --git a/src/core/UBPreferencesController.cpp b/src/core/UBPreferencesController.cpp
index 1c2dc591..f8d2ab90 100644
--- a/src/core/UBPreferencesController.cpp
+++ b/src/core/UBPreferencesController.cpp
@@ -44,6 +44,8 @@
 
 #include "core/memcheck.h"
 
+#include "qdesktopwidget.h"
+
 qreal UBPreferencesController::sSliderRatio = 10.0;
 qreal UBPreferencesController::sMinPenWidth = 0.5;
 qreal UBPreferencesController::sMaxPenWidth = 50.0;
@@ -78,7 +80,7 @@ UBPreferencesController::UBPreferencesController(QWidget *parent)
     mPreferencesUI = new Ui::preferencesDialog();  // deleted in
     mPreferencesUI->setupUi(mPreferencesWindow);
     adjustScreens(1);
-    connect(mDesktop, SIGNAL(screenCountChanged(int)), this, SLOT(adjustScreens(int)));
+    connect(mDesktop, &QDesktopWidget::screenCountChanged, this, &UBPreferencesController::adjustScreens);
 
     wire();
 }