qt设计如何创建彩色面板？

#include <QWidget>
#include <QPainter>
#include <QColor>
#include <QMouseEvent>

class ColorPanel : public QWidget {
    Q_OBJECT

public:
    ColorPanel(QWidget *parent = nullptr) : QWidget(parent), currentColor(Qt::white) {}

protected:
    void paintEvent(QPaintEvent *event) override {
        QPainter painter(this);
        painter.fillRect(rect(), currentColor);
    }

    void mousePressEvent(QMouseEvent *event) override {
        if (event->button() == Qt::LeftButton) {
            changeColor();
            update(); // 请求重绘
        }
    }

private:
    QColor currentColor;

    void changeColor() {
        // 简单的颜色变化逻辑，可以根据需要调整
        int r = qrand() % 256;
        int g = qrand() % 256;
        int b = qrand() % 256;
        currentColor = QColor(r, g, b);
    }
};

// 在主函数中使用ColorPanel
#include <QApplication>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    ColorPanel panel;
    panel.resize(400, 300);
    panel.show();
    return app.exec();
}