QGraphicsview and mouse press event

[eva2002]

Hi all,

I have a problem which need help.

I have a graphicsview which contains a graphicsscene. I want to do something on a mouse click on the graphicsview object.
How can I do this?

mainwindow .h

private:
    QGraphicsEllipseItem *item;
    QGraphicsView *view;
    QGraphicsScene *scene;

private:
    QGraphicsEllipseItem *item;
    QGraphicsView *view;
    QGraphicsScene *scene;

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mainwindow.cpp

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    item = new QGraphicsEllipseItem;
    item->setRect(50, 100, 5, 5); //for setting position and size
    item->setBrush(Qt::red);
 
    scene = new QGraphicsScene;
    scene->setSceneRect(0, 0, 600, 600);
    scene->addItem(item);
 
    view = new QGraphicsView(scene);
    view->setDragMode(QGraphicsView::ScrollHandDrag);
    view->setBackgroundBrush(QPixmap(":/image/map.jpg"));
   ...
}

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    item = new QGraphicsEllipseItem;
    item->setRect(50, 100, 5, 5); //for setting position and size
    item->setBrush(Qt::red);

    scene = new QGraphicsScene;
    scene->setSceneRect(0, 0, 600, 600);
    scene->addItem(item);

    view = new QGraphicsView(scene);
    view->setDragMode(QGraphicsView::ScrollHandDrag);
    view->setBackgroundBrush(QPixmap(":/image/map.jpg"));
   ...
}

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[wagmare]

reimplement the QGraphicsScen
void QGraphicsScene::keyPressEvent ( QKeyEvent * keyEvent ) [virtual protected]

[aamer4yu]

reimplement the QGraphicsScen
void QGraphicsScene::keyPressEvent ( QKeyEvent * keyEvent ) [virtual protected]

I guess you meant QGraphicsScene::mousePressEvent
@Eva
May be if you tell what you want to do on click, we can help you better

[eva2002]

actually I wanted to have something like when I click the mouse on the graphicsview, I will display a circle on that spot and remove any other previously over items items on the scene (except for the background).

which mousepressevent should I edit? the graphicsview, graphicsscene or the graphicellipse?

I have another problem. How can I prevent tiling of the Qpixmap in graphivew if my pixmap is smaller than the scene rect?

[eva2002]

I manage to get the mouse press event to work. However I still have the tiled background issue.

I loaded map onto the graphicsview by using setbackgroundbrush. but I notice that it got tiled if the graphicsScene scene rect is bigger than the map.

How can I prevent this? I want to just white/ block out the areas that is not covered by the map.

Furthermore, I have this scrollbar which will change the size of the map (via matrix transform). I would like the white/black out area to not show after the map is large enough to cover the graphicsScene.

[aamer4yu]

Dont set the brush. Draw the background yourself using QGraphicsScene::drawBackground or QGraphicsView::drawBackground

[eva2002]

thx. by the way, is there any way to remove the background brush after involving setBackgroundBrush?