DAWorkFlowGraphicsScene.h

#ifndef DAWORKFLOWGRAPHICSSCENE_H
#define DAWORKFLOWGRAPHICSSCENE_H
#include <QGraphicsScene>
#include "DAGuiAPI.h"
#include <QHash>
#include <QUndoStack>
#include "DAWorkFlow.h"
#include "DANodeGraphicsScene.h"
 
class QGraphicsSceneWheelEvent;
namespace DA
{
class DAGraphicsPixmapItem;
class DAGUI_API DAWorkFlowGraphicsScene : public DANodeGraphicsScene
{
    Q_OBJECT
public:
    enum SceneActionFlag
    {
        AddRectItemAction,  
        AddTextItemAction   
    };
    Q_ENUM(SceneActionFlag)
public:
    DAWorkFlowGraphicsScene(QObject* parent = 0);
    ~DAWorkFlowGraphicsScene();
    // 设置鼠标动作，一旦设置鼠标动作，鼠标点击后就会触发此动作，continuous来标记动作结束后继续保持还是还原为无动作
    void setPreDefineSceneAction(SceneActionFlag mf);
    //===================================================
    // 背景图相关操作
    //===================================================
    // 设置背景item，如果外部调用getBackgroundPixmapItem并删除，需要通过此函数把保存的item设置为null
    void setBackgroundPixmapItem(DAGraphicsPixmapItem* item);
    DAGraphicsPixmapItem* removeBackgroundPixmapItem();
    // 允许item跟随背景图移动
    void enableItemMoveWithBackground(bool on);
    // 允许移动图元时，其它和此图元链接起来的图元跟随移动
    void setEnableItemLinkageMove(bool on);
    bool isEnableItemLinkageMove() const;
    // 是否item跟随背景图移动
    bool isEnableItemMoveWithBackground() const;
    // 添加一个背景图,如果多次调用，此函数返回的QGraphicsPixmapItem* 是一样的，也就是只会创建一个QGraphicsPixmapItem*
    DAGraphicsPixmapItem* setBackgroundPixmap(const QPixmap& pixmap);
    // 获取背景图item，如果没有设置返回一个nullptr
    DAGraphicsPixmapItem* getBackgroundPixmapItem() const;
 
    // 设置文本字体
    QFont getDefaultTextFont() const;
    void setDefaultTextFont(const QFont& f);
    // 设置文本颜色
    QColor getDefaultTextColor() const;
    void setDefaultTextColor(const QColor& c);
 
protected:
    DAGraphicsPixmapItem* ensureGetBackgroundPixmapItem();
    DAGraphicsPixmapItem* createBackgroundPixmapItem();
 
protected:
#if 0
    virtual void dragEnterEvent(QGraphicsSceneDragDropEvent* event) override;
    virtual void dragMoveEvent(QGraphicsSceneDragDropEvent* event) override;
    virtual void dragLeaveEvent(QGraphicsSceneDragDropEvent* event) override;
    virtual void dropEvent(QGraphicsSceneDragDropEvent* event) override;
#endif
 
private slots:
#if DA_USE_QGRAPHICSOBJECT
    void backgroundPixmapItemXChanged();
    void backgroundPixmapItemYChanged();
#endif
    void onItemsPositionChanged(const QList< QGraphicsItem* >& items,
                                const QList< QPointF >& oldPos,
                                const QList< QPointF >& newPos);
 
private:
    DAGraphicsPixmapItem* mBackgroundPixmapItem;
    SceneActionFlag mMouseAction;           
    bool mEnableItemMoveWithBackground;     
    bool mEnableItemLinkageMove { false };  
    QColor mTextColor;                      
    QFont mTextFont;                        
    QPointF mBackgroundPixmapItemLastPos;   
};
}  // end of namespace DA
#endif  // GGRAPHICSSCENE_H