chore: baseline usable version

libs/qwindowkit/examples/mainwindow/mainwindow.h

@@ -0,0 +1,42 @@
+// Copyright (C) 2023-2024 Stdware Collections (https://www.github.com/stdware)
+// Copyright (C) 2021-2023 wangwenx190 (Yuhang Zhao)
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef MAINWINDOW_H
+#define MAINWINDOW_H
+
+#include <QtWidgets/QMainWindow>
+
+namespace QWK {
+    class WidgetWindowAgent;
+    class StyleAgent;
+}
+
+class MainWindow : public QMainWindow {
+    Q_OBJECT
+public:
+    explicit MainWindow(QWidget *parent = nullptr);
+    ~MainWindow() override;
+
+    enum Theme {
+        Dark,
+        Light,
+    };
+    Q_ENUM(Theme)
+
+Q_SIGNALS:
+    void themeChanged();
+
+protected:
+    bool event(QEvent *event) override;
+
+private:
+    void installWindowAgent();
+    void loadStyleSheet(Theme theme);
+
+    Theme currentTheme{};
+
+    QWK::WidgetWindowAgent *windowAgent;
+};
+
+#endif // MAINWINDOW_H