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# QGraphicsSceneEvent Class Reference
[com.trolltech.qt.gui module]

The `QGraphicsSceneEvent` class provides a base class for all graphics view related events. More...

Inherits `QEvent`.

Inherited by `QGraphicsSceneContextMenuEvent`, `QGraphicsSceneDragDropEvent`, `QGraphicsSceneHelpEvent`, `QGraphicsSceneHoverEvent`, `QGraphicsSceneMouseEvent`, and `QGraphicsSceneWheelEvent`.

## Detailed Description

The `QGraphicsSceneEvent` class provides a base class for all graphics view related events.

When a `QGraphicsView` receives Qt mouse, keyboard, and drag and drop events (`QMouseEvent`, `QKeyEvent`, QDragEvent, etc.), it translates them into instances of `QGraphicsSceneEvent` subclasses and forwards them to the `QGraphicsScene` it displays. The scene then forwards the events to the relevant items.

For example, when a `QGraphicsView` receives a `QMouseEvent` of type MousePress as a response to a user click, the view sends a `QGraphicsSceneMouseEvent` of type `GraphicsSceneMousePress` to the underlying `QGraphicsScene` through its mousePressEvent() function. The default QGraphicsScene::mousePressEvent() implementation determines which item was clicked and forwards the event to QGraphicsItem::mousePressEvent().

Subclasses such as `QGraphicsSceneMouseEvent` and `QGraphicsSceneContextMenuEvent` provide the coordinates from the original `QEvent` in screen, scene, and item coordinates (see screenPos(), scenePos(), and pos()). The item coordinates are set by the `QGraphicsScene` before it forwards the event to the event to a `QGraphicsItem`. The mouse events also add the possibility to retrieve the coordinates from the last event received by the view (see lastScreenPos(), lastScenePos(), and lastPos()).

See also `QEvent`.