qt 绘制流程图示例程序——Diagram

#include <QGraphicsScene> #include <QGraphicsView> #include <QColorDialog> #include <QMenu> #include <QClipboard> #include <QMenuBar> #include <QToolBar> #include "diagramwindow.h" #include "link.h" #include "node.h" #include "propertiesdialog.h" DiagramWindow::DiagramWindow() { scene = new QGraphicsScene(0, 0, 600, 500); view = new QGraphicsView; view->setScene(scene); view->setDragMode(QGraphicsView::RubberBandDrag); view->setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing); view->setContextMenuPolicy(Qt::ActionsContextMenu); setCentralWidget(view); minZ = 0; maxZ = 0; seqNumber = 0; createActions(); createMenus(); createToolBars(); connect(scene, SIGNAL(selectionChanged()), this, SLOT(updateActions())); setWindowTitle(tr("Diagram")); updateActions(); } void DiagramWindow::addNode() { Node *node = new Node; node->setText(tr("Node %1").arg(seqNumber + 1)); setupNode(node); } void DiagramWindow::addLink() { NodePair nodes = selectedNodePair(); if (nodes == NodePair()) return; Link *link = new Link(nodes.first, nodes.second); scene->addItem(link); } void DiagramWindow::del() { QList<QGraphicsItem *> items = scene->selectedItems(); QMutableListIterator<QGraphicsItem *> i(items); while (i.hasNext()) { Link *link = dynamic_cast<Link *>(i.next()); if (link) { delete link; i.remove(); } } qDeleteAll(items); } void DiagramWindow::cut() { Node *node = selectedNode(); if (!node) return; copy(); delete node; } void DiagramWindow::copy() { Node *node = selectedNode(); if (!node) return; QString str = QString("Node %1 %2 %3 %4") .arg(node->textColor().name()) .arg(node->outlineColor().name()) .arg(node->backgroundColor().name()) .arg(node->text()); QApplication::clipboard()->setText(str); } void DiagramWindow::paste() { QString str = QApplication::clipboard()->text(); QStringList parts = str.split(" "); if (parts.count() >= 5 && parts.first() == "Node") { Node *node = new Node; node->setText(QStringList(parts.mid(4)).join(" ")); node->setTextColor(QColor(parts[1])); node->setOutlineColor(QColor(parts[2])); node->setBackgroundColor(QColor(parts[3])); setupNode(node); } } void DiagramWindow::bringToFront() { ++maxZ; setZValue(maxZ); } void DiagramWindow::sendToBack() { --minZ; setZValue(minZ); } void DiagramWindow::properties() { Node *node = selectedNode(); Link *link = selectedLink(); if (node) { PropertiesDialog dialog(node, this); dialog.exec(); } else if (link) { QColor color = QColorDialog::getColor(link->color(), this); if (color.isValid()) link->setColor(color); } } void DiagramWindow::updateActions() { bool hasSelection = !scene->selectedItems().isEmpty(); bool isNode = (selectedNode() != 0); bool isNodePair = (selectedNodePair() != NodePair()); cutAction->setEnabled(isNode); copyAction->setEnabled(isNode); addLinkAction->setEnabled(isNodePair); deleteAction->setEnabled(hasSelection); bringToFrontAction->setEnabled(isNode); sendToBackAction->setEnabled(isNode); propertiesAction->setEnabled(isNode); foreach (QAction *action, view->actions()) view->removeAction(action); foreach (QAction *action, editMenu->actions()) { if (action->isEnabled()) view->addAction(action); } } void DiagramWindow::createActions() { exitAction = new QAction(tr("E&xit"), this); exitAction->setShortcut(tr("Ctrl+Q")); connect(exitAction, SIGNAL(triggered()), this, SLOT(close())); addNodeAction = new QAction(tr("Add &Node"), this); addNodeAction->setIcon(QIcon(":/images/node.png")); addNodeAction->setShortcut(tr("Ctrl+N")); connect(addNodeAction, SIGNAL(triggered()), this, SLOT(addNode())); addLinkAction = new QAction(tr("Add &Link"), this); addLinkAction->setIcon(QIcon(":/images/link.png")); addLinkAction->setShortcut(tr("Ctrl+L")); connect(addLinkAction, SIGNAL(triggered()), this, SLOT(addLink())); deleteAction = new QAction(tr("&Delete"), this); deleteAction->setIcon(QIcon(":/images/delete.png")); deleteAction->setShortcut(tr("Del")); connect(deleteAction, SIGNAL(triggered()), this, SLOT(del())); cutAction = new QAction(tr("Cu&t"), this); cutAction->setIcon(QIcon(":/images/cut.png")); cutAction->setShortcut(tr("Ctrl+X")); connect(cutAction, SIGNAL(triggered()), this, SLOT(cut())); copyAction = new QAction(tr("&Copy"), this); copyAction->setIcon(QIcon(":/images/copy.png")); copyAction->setShortcut(tr("Ctrl+C")); connect(copyAction, SIGNAL(triggered()), this, SLOT(copy())); pasteAction = new QAction(tr("&Paste"), this); pasteAction->setIcon(QIcon(":/images/paste.png")); pasteAction->setShortcut(tr("Ctrl+V")); connect(pasteAction, SIGNAL(triggered()), this, SLOT(paste())); bringToFrontAction = new QAction(tr("Bring to &Front"), this); bringToFrontAction->setIcon(QIcon(":/images/bringtofront.png")); connect(bringToFrontAction, SIGNAL(triggered()), this, SLOT(bringToFront())); sendToBackAction = new QAction(tr("&Send to Back"), this); sendToBackAction->setIcon(QIcon(":/images/sendtoback.png")); connect(sendToBackAction, SIGNAL(triggered()), this, SLOT(sendToBack())); propertiesAction = new QAction(tr("P&roperties..."), this); connect(propertiesAction, SIGNAL(triggered()), this, SLOT(properties())); } void DiagramWindow::createMenus() { fileMenu = menuBar()->addMenu(tr("&File")); fileMenu->addAction(exitAction); editMenu = menuBar()->addMenu(tr("&Edit")); editMenu->addAction(addNodeAction); editMenu->addAction(addLinkAction); editMenu->addAction(deleteAction); editMenu->addSeparator(); editMenu->addAction(cutAction); editMenu->addAction(copyAction); editMenu->addAction(pasteAction); editMenu->addSeparator(); editMenu->addAction(bringToFrontAction); editMenu->addAction(sendToBackAction); editMenu->addSeparator(); editMenu->addAction(propertiesAction); } void DiagramWindow::createToolBars() { editToolBar = addToolBar(tr("Edit")); editToolBar->addAction(addNodeAction); editToolBar->addAction(addLinkAction); editToolBar->addAction(deleteAction); editToolBar->addSeparator(); editToolBar->addAction(cutAction); editToolBar->addAction(copyAction); editToolBar->addAction(pasteAction); editToolBar->addSeparator(); editToolBar->addAction(bringToFrontAction); editToolBar->addAction(sendToBackAction); } void DiagramWindow::setZValue(int z) { Node *node = selectedNode(); if (node) node->setZValue(z); } void DiagramWindow::setupNode(Node *node) { node->setPos(QPoint(80 + (100 * (seqNumber % 5)), 80 + (50 * ((seqNumber / 5) % 7)))); scene->addItem(node); ++seqNumber; scene->clearSelection(); node->setSelected(true); bringToFront(); } Node *DiagramWindow::selectedNode() const { QList<QGraphicsItem *> items = scene->selectedItems(); if (items.count() == 1) { return dynamic_cast<Node *>(items.first()); } else { return 0; } } Link *DiagramWindow::selectedLink() const { QList<QGraphicsItem *> items = scene->selectedItems(); if (items.count() == 1) { return dynamic_cast<Link *>(items.first()); } else { return 0; } } DiagramWindow::NodePair DiagramWindow::selectedNodePair() const { QList<QGraphicsItem *> items = scene->selectedItems(); if (items.coun