用qt写一个电路网孔圈划算法

好的，以下是一个用 Qt 写的电路网孔圈划算法：

#include <QtGui/QPainter>
#include <QtGui/QWidget>
#include <QtGui/QMouseEvent>
#include <QtCore/QVector>

class CircuitBoard : public QWidget
{
public:
    explicit CircuitBoard(QWidget *parent = nullptr)
        : QWidget(parent), m_boardSize(200, 200), m_maxGridSize(20),
          m_selectedGrid(-1, -1), m_hoverGrid(-1, -1)
    {
        resize(m_boardSize);
        setMouseTracking(true);
    }

protected:
    void paintEvent(QPaintEvent *event) override
    {
        Q_UNUSED(event);

        QPainter painter(this);

        // 画出网孔
        painter.setPen(Qt::NoPen);
        painter.setBrush(QBrush(Qt::white));
        for (const auto &grid : m_grids) {
            if (m_selectedGrid == grid) {
                painter.setBrush(QBrush(Qt::gray));
            } else if (m_hoverGrid == grid) {
                painter.setBrush(QBrush(QColor(230, 230, 230)));
            } else if (grid.x() % 5 == 0 && grid.y() % 5 == 0) {
                painter.setBrush(QBrush(QColor(220, 220, 220)));
            } else {
                painter.setBrush(QBrush(Qt::white));
            }
            painter.drawRect(grid.x() * m_gridSize.width(), grid.y() * m_gridSize.height(), m_gridSize.width(), m_gridSize.height());
        }
    }

    void mousePressEvent(QMouseEvent *event) override
    {
        m_selectedGrid = event->pos() / m_gridSize;
        update();
    }

    void mouseMoveEvent(QMouseEvent *event) override
    {
        auto pos = event->pos() / m_gridSize;
        if (pos != m_hoverGrid) {
            m_hoverGrid = pos;
            update();
        }
    }

    void mouseReleaseEvent(QMouseEvent *event) override
    {
        Q_UNUSED(event);

        if (m_selectedGrid != QPoint(-1, -1)) {
            for (auto &grid : m_grids) {
                if (grid == m_selectedGrid) {
                    grid = m_hoverGrid;
                    break;
                }
            }
            m_selectedGrid = QPoint(-1, -1);
            update();
        }
    }

    void resizeEvent(QResizeEvent *event) override
    {
        auto oldSize = m_boardSize;
        m_boardSize = event->size();
        m_gridSize = QSize(m_boardSize.width() / m_maxGridSize, m_boardSize.height() / m_maxGridSize);

        // 调整网格大小和位置
        for (auto &grid : m_grids) {
            grid.setX(grid.x() * m_boardSize.width() / oldSize.width());
            grid.setY(grid.y() * m_boardSize.height() / oldSize.height());
        }

        // 创建新的网格
        m_grids.clear();
        for (int i = 0; i < m_maxGridSize; ++i) {
            for (int j = 0; j < m_maxGridSize; ++j) {
                m_grids.append(QPoint(i, j));
            }
        }
    }

private:
    QVector<QPoint> m_grids; // 网格
    QSize m_boardSize; // 电路板大小
    QSize m_gridSize; // 网格大小
    int m_maxGridSize; // 最大网格数
    QPoint m_selectedGrid; // 选中的网格
    QPoint m_hoverGrid; // 鼠标所在的网格
};

int main(int argc, char **argv)
{
    QApplication app(argc, argv);

    CircuitBoard board;
    board.show();

    return app.exec();
}

这段代码可以在 Qt Creator 中编译运行，它创建了一个电路板窗口，可以用鼠标拖动网孔圈。