diff --git a/.gitignore b/.gitignore
index ee4c926..513eaeb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
-/test
+build
+*.kdev4
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6bb3e57..4123d62 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8.11)
+cmake_minimum_required(VERSION 3.0.2 FATAL_ERROR)
 project(lxqt-qtplugin)
 
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
@@ -10,11 +10,7 @@ find_package(Qt5LinguistTools REQUIRED QUIET)
 
 find_package(lxqt REQUIRED QUIET)
 
-include(${LXQT_USE_FILE})
-
-if(CMAKE_COMPILER_IS_GNUCXX)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-exceptions -Wl,-no-undefined -Wall")
-endif()
+include(LXQtCompilerSettings NO_POLICY_SCOPE)
 
 add_subdirectory(src)
 
diff --git a/lxqt-qtplugin.kdev4 b/lxqt-qtplugin.kdev4
deleted file mode 100644
index 740812d..0000000
--- a/lxqt-qtplugin.kdev4
+++ /dev/null
@@ -1,3 +0,0 @@
-[Project]
-Manager=KDevCMakeManager
-Name=lxqt-qtplugin
diff --git a/src/lxqtplatformtheme.cpp b/src/lxqtplatformtheme.cpp
index a7b5edc..51f0166 100644
--- a/src/lxqtplatformtheme.cpp
+++ b/src/lxqtplatformtheme.cpp
@@ -43,6 +43,7 @@
 #include <QDir>
 #include <QFileInfo>
 #include <QFileSystemWatcher>
+#include <QStyle>
 #include "qiconloader_p.h"
 
 LXQtPlatformTheme::LXQtPlatformTheme():
@@ -157,7 +158,11 @@ void LXQtPlatformTheme::onSettingsChanged() {
     loadSettings(); // reload the config file
 
     if(style_ != oldStyle) // the widget style is changed
-        qApp->setStyle(style_); // ask Qt5 to apply the new style
+    {
+        // ask Qt5 to apply the new style
+        if (qobject_cast<QApplication *>(QCoreApplication::instance()))
+            QApplication::setStyle(style_);
+    }
 
     if(iconTheme_ != oldIconTheme) { // the icon theme is changed
         QIconLoader::instance()->updateSystemTheme(); // this is a private internal API of Qt5.
@@ -198,12 +203,15 @@ bool LXQtPlatformTheme::usePlatformNativeDialog(DialogType type) const {
 QPlatformDialogHelper *LXQtPlatformTheme::createPlatformDialogHelper(DialogType type) const {
     return 0;
 }
+#endif
 
 const QPalette *LXQtPlatformTheme::palette(Palette type) const {
-    return new QPalette();
-}
 
-#endif
+    if (type == QPlatformTheme::SystemPalette)
+        // the default constructor uses the default palette
+        return new QPalette;
+    return QPlatformTheme::palette(type);
+}
 
 const QFont *LXQtPlatformTheme::font(Font type) const {
 	// qDebug() << "font()" << type << SystemFont;
@@ -250,7 +258,7 @@ QVariant LXQtPlatformTheme::themeHint(ThemeHint hint) const {
     case ItemViewActivateItemOnSingleClick:
         return QVariant(singleClickActivate_);
     case SystemIconThemeName:
-        qDebug() << "iconTheme" << iconTheme_;
+        // qDebug() << "iconTheme" << iconTheme_;
         return iconTheme_;
     case SystemIconFallbackThemeName:
         return "hicolor";
diff --git a/src/lxqtplatformtheme.h b/src/lxqtplatformtheme.h
index abba806..42f8ccf 100644
--- a/src/lxqtplatformtheme.h
+++ b/src/lxqtplatformtheme.h
@@ -24,7 +24,7 @@
  * Boston, MA 02110-1301 USA
  *
  * END_COMMON_COPYRIGHT_HEADER */
- 
+
 #ifndef LXQTPLATFORMTHEME_H
 #define LXQTPLATFORMTHEME_H
 
@@ -48,7 +48,7 @@ public:
     virtual bool usePlatformNativeDialog(DialogType type) const;
     // virtual QPlatformDialogHelper *createPlatformDialogHelper(DialogType type) const;
 
-    // virtual const QPalette *palette(Palette type = SystemPalette) const;
+    virtual const QPalette *palette(Palette type = SystemPalette) const;
 
     virtual const QFont *font(Font type = SystemFont) const;