Add dependency on QtQuickControls2 to correctly style timeline controls

CMakeLists.txt

@@ -57,7 +57,7 @@ find_package(KF5 REQUIRED COMPONENTS Archive Bookmarks CoreAddons Config ConfigW
 
 # Qt
 set(QT_MIN_VERSION 5.11.0)
-find_package(Qt5 REQUIRED COMPONENTS Core DBus Widgets Svg Quick Concurrent QuickWidgets Multimedia)
+find_package(Qt5 REQUIRED COMPONENTS Core DBus Widgets Svg Quick QuickControls2 Concurrent QuickWidgets Multimedia)
 add_definitions(-DQT_NO_CAST_TO_ASCII -DQT_NO_URL_CAST_FROM_STRING)
 set(DEFAULT_CXX_FLAGS "${DEFAULT_CXX_FLAGS} ${Qt5Widgets_EXECUTABLE_COMPILE_FLAGS}")
 

src/CMakeLists.txt

@@ -131,6 +131,7 @@ target_link_libraries(kdenliveLib
     KF5::Solid
     Qt5::Svg
     Qt5::Quick
+    Qt5::QuickControls2
     Qt5::QuickWidgets
     Qt5::Concurrent
     Qt5::Multimedia

src/core.cpp

@@ -36,7 +36,7 @@ the Free Software Foundation, either version 3 of the License, or
 #include <QCoreApplication>
 #include <QInputDialog>
 #include <QDir>
-
+#include <QQuickStyle>
 #include <locale>
 #ifdef Q_OS_MAC
 #include <xlocale.h>
@@ -127,6 +127,13 @@ void Core::initGUI(const QUrl &Url, const QString &clipsToLoad)
     m_currentProfile = m_profile;
     profileChanged();
     m_mainWindow = new MainWindow();
+    QStringList styles = QQuickStyle::availableStyles();
+    if (styles.contains(QLatin1String("org.kde.desktop"))) {
+        QQuickStyle::setStyle("org.kde.desktop");
+    } else if (styles.contains(QLatin1String("Fusion"))) {
+        QQuickStyle::setStyle("Fusion");
+    }
+
     connect(this, &Core::showConfigDialog, m_mainWindow, &MainWindow::slotPreferences);
 
     // load default profile and ask user to select one if not found.