editor/customgraphicsscene.cpp

#include "customgraphicsscene.h"
#include <QGraphicsSceneMouseEvent>
#include <QGraphicsView>
#include <QKeyEvent>
#include <QGuiApplication>
#include <QMenu>

// 实现新的构造函数
CustomGraphicsScene::CustomGraphicsScene(QGraphicsView* view, QObject *parent)
    : QGraphicsScene(parent), m_mode(Normal), m_view(view)
{
    // 断言确保传入的 view 是有效的
    Q_ASSERT(m_view);
}

void CustomGraphicsScene::setMode(Mode mode)
{
    if (m_mode == mode) return;

    m_mode = mode;

    // 根据模式设置光标
    if (m_mode == CreateItem) {
        m_view->setCursor(Qt::CrossCursor);
    } else {
        m_view->setCursor(Qt::ArrowCursor); // 恢复为标准箭头光标
    }
}

// setComponentTypeToCreate 函数无需改动
void CustomGraphicsScene::setComponentTypeToCreate(ComponentType type)
{
    m_componentTypeToCreate = type;
}

// mousePressEvent 函数无需改动
void CustomGraphicsScene::mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
    if (mouseEvent->button() != Qt::LeftButton) {
        QGraphicsScene::mousePressEvent(mouseEvent);
        return;
    }

    if (m_mode == CreateItem) {
        HmiComponent* item = nullptr;

        switch (m_componentTypeToCreate) {
        case ComponentType::Button:
            item = new HmiButton();
            break;
        case ComponentType::Indicator:
            item = new HmiIndicator();
            break;
        }

        if (item)
        {
            item->setPos(mouseEvent->scenePos());
            if (item->scene() == nullptr)
            {
                addItem(item);
                emit componentCreated(item);
            }
            else
            {
                // 如果 item 已经被添加到场景中，则删除它，避免内存泄漏
                delete item;
            }
        }

        setMode(Normal);
    }
    else
    {
        QGraphicsScene::mousePressEvent(mouseEvent);
    }
}

// mouseMoveEvent 函数无需改动
void CustomGraphicsScene::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
    QGraphicsScene::mouseMoveEvent(mouseEvent);
}


// 修改或新增 keyPressEvent
void CustomGraphicsScene::keyPressEvent(QKeyEvent *keyEvent)
{
    // 退出创建模式
    if (keyEvent->key() == Qt::Key_Escape && m_mode == CreateItem) {
        setMode(Normal);
        keyEvent->accept();
        return;
    }

    // 处理删除、复制、粘贴
    if (selectedItems().isEmpty()) {
        QGraphicsScene::keyPressEvent(keyEvent);
        return;
    }

    switch (keyEvent->key()) {
    case Qt::Key_Delete:
        emit deleteRequestFromScene();
        keyEvent->accept();
        break;
    case Qt::Key_C:
        if (keyEvent->modifiers() & Qt::ControlModifier) {
            emit copyRequestFromScene();
            keyEvent->accept();
        }
        break;
    case Qt::Key_V:
        if (keyEvent->modifiers() & Qt::ControlModifier) {
            // 使用与 contextMenuEvent 相同的方式获取粘贴位置
            QPointF pastePos = views().first()->mapToScene(views().first()->viewport()->mapFromGlobal(QCursor::pos()));
            emit pasteRequestFromScene(pastePos);
            keyEvent->accept();
        }
        break;
    default:
        break;
    }

    QGraphicsScene::keyPressEvent(keyEvent);
}

void CustomGraphicsScene::contextMenuEvent(QGraphicsSceneContextMenuEvent *contextMenuEvent)
{
    // 检查鼠标下方是否有图形项
    QGraphicsItem *item = itemAt(contextMenuEvent->scenePos(), views().first()->transform());

    if (!item) {
        // 如果点击在空白处，则显示我们的粘贴菜单
        contextMenuEvent->accept();

        QMenu menu;
        QAction *pasteAction = menu.addAction("粘贴");

        // 将菜单动作连接到场景的粘贴请求信号
        connect(pasteAction, &QAction::triggered, this, [this, contextMenuEvent]() {
            emit pasteRequestFromScene(contextMenuEvent->scenePos());
        });

        menu.exec(contextMenuEvent->screenPos());
    } else {
        // 如果点击在图形项上，则将事件传递给该图形项处理(这会调用 HmiComponent::contextMenuEvent)
        QGraphicsScene::contextMenuEvent(contextMenuEvent);
    }
}