view.cpp Example File

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  #include "informationwindow.h"
  #include "imageitem.h"
  #include "view.h"

  View::View(const QString &items, const QString &images, QWidget *parent)
      : QGraphicsView(parent)
  {
      itemTable = new QSqlRelationalTableModel(this);
      itemTable->setTable(items);
      itemTable->setRelation(1, QSqlRelation(images, "itemid", "file"));
      itemTable->select();

      scene = new QGraphicsScene(this);
      scene->setSceneRect(0, 0, 465, 365);
      setScene(scene);

      addItems();

      setMinimumSize(470, 370);
      setMaximumSize(470, 370);

      QLinearGradient gradient(QPointF(0, 0), QPointF(0, 370));
      gradient.setColorAt(0, QColor("#868482"));
      gradient.setColorAt(1, QColor("#5d5b59"));
      setBackgroundBrush(gradient);
  }

  void View::addItems()
  {
      int itemCount = itemTable->rowCount();

      int imageOffset = 150;
      int leftMargin = 70;
      int topMargin = 40;

      for (int i = 0; i < itemCount; i++) {
          ImageItem *image;
          QGraphicsTextItem *label;
          QSqlRecord record = itemTable->record(i);

          int id = record.value("id").toInt();
          QString file = record.value("file").toString();
          QString item = record.value("itemtype").toString();

          int columnOffset = ((i % 2) * 37);
          int x = ((i % 2) * imageOffset) + leftMargin + columnOffset;
          int y = ((i / 2) * imageOffset) + topMargin;

          image = new ImageItem(id, QPixmap(":/" + file));
          image->setData(0, i);
          image->setPos(x, y);
          scene->addItem(image);

          label = scene->addText(item);
          label->setDefaultTextColor(QColor("#d7d6d5"));
          QPointF labelOffset((120 - label->boundingRect().width()) / 2, 120.0);
          label->setPos(QPointF(x, y) + labelOffset);
      }
  }

  void View::mouseReleaseEvent(QMouseEvent *event)
  {
      if (QGraphicsItem *item = itemAt(event->pos())) {
          if (ImageItem *image = qgraphicsitem_cast<ImageItem *>(item))
              showInformation(image);
      }
      QGraphicsView::mouseReleaseEvent(event);
  }

  void View::showInformation(ImageItem *image)
  {
      int id = image->id();
      if (id < 0 || id >= itemTable->rowCount())
          return;

      InformationWindow *window = findWindow(id);
      if (window && window->isVisible()) {
          window->raise();
          window->activateWindow();
      } else if (window && !window->isVisible()) {
          window->show();
      } else {
          InformationWindow *window;
          window = new InformationWindow(id, itemTable, this);

          connect(window, SIGNAL(imageChanged(int,QString)),
                  this, SLOT(updateImage(int,QString)));

          window->move(pos() + QPoint(20, 40));
          window->show();
          informationWindows.append(window);
      }
  }

  void View::updateImage(int id, const QString &fileName)
  {
      QList<QGraphicsItem *> items = scene->items();

      while(!items.empty()) {
          QGraphicsItem *item = items.takeFirst();

          if (ImageItem *image = qgraphicsitem_cast<ImageItem *>(item)) {
              if (image->id() == id){
                  image->setPixmap(QPixmap(":/" +fileName));
                  image->adjust();
                  break;
              }
          }
      }
  }

  InformationWindow* View::findWindow(int id)
  {
      QList<InformationWindow*>::iterator i, beginning, end;

      beginning = informationWindows.begin();
      end = informationWindows.end();

      for (i = beginning; i != end; ++i) {
          InformationWindow *window = (*i);
          if (window && (window->id() == id))
              return window;
      }
      return 0;
  }