#8 - Undo move and add components

logicsim.pro

@@ -22,7 +22,8 @@ SOURCES += src/main.cpp \
     src/gates.cpp \
     src/connectionline.cpp \
     src/workspacetab.cpp \
-    src/pin.cpp
+    src/pin.cpp \
+    src/commands.cpp
 
 HEADERS += src/mainwindow.h \
     src/canvas.h \
@@ -35,7 +36,8 @@ HEADERS += src/mainwindow.h \
     src/connectionline.h \
     src/gates.h \
     src/workspacetab.h \
-    src/pin.h
+    src/pin.h \
+    src/commands.h
 
 FORMS += src/mainwindow.ui
 

src/canvas.cpp

@@ -8,6 +8,7 @@
 // Local includes
 
 #include "pin.h"
+#include "commands.h"
 #include "logicsim_global.h"
 
 namespace Logicsim
@@ -36,6 +37,12 @@ class Canvas::Private
 Canvas::Canvas(QObject *parent)
     : QGraphicsScene(parent), d(new Private)
 {
+    undoStack = new QUndoStack(this);
+    createUndoView();
+
+    connect(this, SIGNAL(itemMoved(Component*,QPointF)),this,SLOT(itemMovedS(Component*,QPointF)));
+    connect(this,SIGNAL(itemAdded(Component*,QPointF)),this,SLOT(itemAddedS(Component*,QPointF)));
+
     d->view = new QGraphicsView(this);
     d->view->setSceneRect(0,0,CANVAS_WIDTH,CANVAS_HEIGHT);
 
@@ -94,6 +101,7 @@ void Canvas::dropEvent(QGraphicsSceneDragDropEvent * event)
 
         Component* component = static_cast<Component*>(QMetaType::create(typeId));
         d->mCanvasManager->addComponent(component, event->scenePos());
+        emit itemAdded(component,component->pos());
     }
     else
     {
@@ -174,6 +182,12 @@ void Canvas::mousePressEvent(QGraphicsSceneMouseEvent *event)
         {
             d->mCanvasManager->pinPressed(p);
         }
+
+        Component *component = dynamic_cast<Component*>(mouseGrabberItem());
+        if(component)
+        {
+         oldpt = component->pos();
+        }
     }
     else
     {
@@ -215,6 +229,7 @@ void Canvas::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
             d->mCanvasManager->movingComponent(component);
             d->mCanvasManager->componentMoved(component, event->scenePos());
             d->view->setCursor(Qt::ArrowCursor);
+            emit itemMoved(component,component->pos());
         }
     }
     QGraphicsScene::mouseReleaseEvent(event);
@@ -248,5 +263,31 @@ void Canvas::drawBackground(QPainter *painter, const QRectF &rect)
     }
 }
 
+void Canvas::itemMovedS(Component *item, const QPointF &pos)
+{
+    Q_UNUSED(pos);
+    pushInStack(new MoveCommand(item,oldpt));
+    update();
+}
+
+void Canvas::itemAddedS(Component *addedItem, const QPointF &position)
+{
+    Q_UNUSED(position);
+    pushInStack(new AddCommand(addedItem,this));
+}
+
+void Canvas::pushInStack(QUndoCommand* command)
+{
+    undoStack->push(command);
+    qDebug()<<"..............pushed";
+}
+
+void Canvas::createUndoView()
+{
+    undoView = new QUndoView(undoStack);
+    undoView->show();
+    undoView->setAttribute(Qt::WA_QuitOnClose, false);
+}
+
 } // namespace Logicsim
 

src/canvas.h

@@ -31,6 +31,8 @@ class Canvas : public QGraphicsScene
     int tabIndex() const;
     void setTabIndex(int index);
     CanvasManager *canvasManager();
+    void createUndoView();
+    void pushInStack(QUndoCommand* command);
 
 protected:
     void dropEvent(QGraphicsSceneDragDropEvent * event);
@@ -52,6 +54,18 @@ public Q_SLOTS:
 private:
     class Private;
     Private* const d;
+
+    QUndoStack *undoStack;
+    QUndoView *undoView;
+    QPointF oldpt;
+
+signals:
+    void itemMoved(Component *movedItem, const QPointF &movedFromPosition);
+    void itemAdded(Component *addedItem, const QPointF &position);
+
+private slots:
+    void itemMovedS(Component *item, const QPointF &pos);
+    void itemAddedS(Component *item, const QPointF &pos);
 };
 
 } // namespace Logicsim

src/commands.cpp

@@ -0,0 +1,63 @@
+#include "commands.h"
+
+namespace Logicsim
+{
+
+MoveCommand::MoveCommand(Component *Mcomponent, const QPointF &MOldPos,QUndoCommand *parent) : QUndoCommand(parent)
+{
+    draggedComponent = Mcomponent;
+    newPos = Mcomponent->pos();
+    oldPos = MOldPos;
+}
+
+void MoveCommand::undo()
+{
+    draggedComponent->setPos(oldPos);
+    setText(QObject::tr("Move %1").arg(createCommandString(draggedComponent, newPos)));
+}
+
+void MoveCommand::redo()
+{
+    draggedComponent->setPos(newPos);
+    setText(QObject::tr("Move %1").arg(createCommandString(draggedComponent, newPos)));
+}
+
+AddCommand::AddCommand(Component *Acomponent, Canvas *Acanvas,QUndoCommand *parent) : QUndoCommand(parent)
+{
+    static int itemCount = 0;
+
+    canvas = Acanvas;
+    addedComponent = Acomponent;
+    pos = Acomponent->pos();
+
+    Acanvas->update();
+    ++itemCount;
+    setText(QObject::tr("Add %1").arg(createCommandString(addedComponent, pos)));
+}
+
+AddCommand::~AddCommand()
+{
+    if (!addedComponent->scene())
+        delete addedComponent;
+}
+
+void AddCommand::undo()
+{
+    canvas->removeItem(addedComponent);
+    canvas->update();
+}
+
+void AddCommand::redo()
+{
+    canvas->addItem(addedComponent);
+    addedComponent->setPos(pos);
+    canvas->clearSelection();
+    canvas->update();
+}
+
+QString createCommandString(Component *item, const QPointF &pos)
+{
+    return QObject::tr("%2, %3").arg(pos.x()).arg(pos.y());
+}
+
+} //LogicSim

src/commands.h

@@ -0,0 +1,42 @@
+#ifndef COMMANDS_H
+#define COMMANDS_H
+
+#include <QUndoCommand>
+
+#include "component.h"
+#include "canvas.h"
+
+namespace Logicsim
+{
+
+class MoveCommand : public QUndoCommand
+{
+public:
+    MoveCommand(Component *Mcomponent, const QPointF &MOldPos,QUndoCommand *parent = 0);
+    void undo() Q_DECL_OVERRIDE;
+    void redo() Q_DECL_OVERRIDE;
+
+private:
+    Component *draggedComponent;
+    QPointF oldPos;
+    QPointF newPos;
+};
+
+class AddCommand : public QUndoCommand
+{
+public:
+    AddCommand(Component *Acomponent, Canvas *Acanvas,QUndoCommand *parent = 0);
+    ~AddCommand();
+    void undo() Q_DECL_OVERRIDE;
+    void redo() Q_DECL_OVERRIDE;
+
+private:
+    Component *addedComponent;
+    Canvas *canvas;
+    QPointF pos;
+};
+
+QString createCommandString(Component *item, const QPointF &point);
+
+}
+#endif // COMMANDS_H