diff --git a/src/app-itemdelegate.h b/src/app-itemdelegate.h
index d347373..27f3ab8 100644
--- a/src/app-itemdelegate.h
+++ b/src/app-itemdelegate.h
@@ -39,6 +39,6 @@ protected:
     virtual QSize sizeHint(const QStyleOptionViewItem& option, const QModelIndex& index) const;
 
 private:
-    int m_iconSize;
+    int m_iconSize = 32;
     int m_maxTextWidth = 0;
 };
diff --git a/src/app-model.h b/src/app-model.h
index 2a3e6e7..7dada81 100644
--- a/src/app-model.h
+++ b/src/app-model.h
@@ -31,7 +31,7 @@
 
 struct AppInfo
 {
-    WId     windowId;
+    WId     windowId = 0;
     QString name;
     QPixmap pixmap;
 };
diff --git a/src/main.cpp b/src/main.cpp
index b5e9e34..c904e99 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -51,11 +51,11 @@ int main(int argc, char* argv[])
     app.setQuitOnLastWindowClosed(false);
 
     LXQt::LXQtTheme theme = currentTheme();
-    if (QFile::exists(theme.path() + "/lxqt-app-switcher.qss")) {
-        app.setStyleSheet("file:///" + theme.path() + "/lxqt-app-switcher.qss");
+    if (QFile::exists(theme.path() + QLatin1String("/lxqt-app-switcher.qss"))) {
+        app.setStyleSheet(QLatin1String("file:///%1/lxqt-app-switcher.qss").arg(theme.path()));
     }
 
-    QWidget     hiddenPreviewParent(0, Qt::Tool);
+    QWidget     hiddenPreviewParent(nullptr, Qt::Tool);
     AppSwitcher switcher(&hiddenPreviewParent);
 
     return app.exec();