Graphics View major class structure comprising: view class QGraphicsView, scene classes QGraphicsScene, and various graphical item class (classes are QGraphicsItem yl)
1. QGraphicsView physical window for viewing a scene
View the scene is less than the entire scene visible in the view; view when a scene is greater than an attempt to automatically provide volumes of the roller
QGraphicsView viewport coordinates equal to the coordinates of the physical display device, but may be a translation of coordinates QGraphicsView, rotation and scaling
Interface function is provided as follows:
| Scenes | void setScene（） | // set the scene associated |
| void setSceneRect（） | // scene visible in the view area of the rectangular portion | |
| Exterior | setAlignment void () | // set the alignment of the scene in view |
| void setBackgroundBrush（） | ||
| void setForegroundBrush（） | ||
| void setRenderHints（ ） | // Set drawing options | |
| Alternately | void setInteractive（） | Interactive |
| QRect rubberBandRect | Back to selection rectangle | |
| void setRubberBandSelectionMode（） | Selection Mode | |
| QGraphicsItem *itemAt（） | Get the view coordinate system at a location graphical items | |
| QList<QGraphicsItem *> items() | Get a list of all or a selected area of the graphic item in the scene | |
| coordinate | QPoint mapFormScene | Converting a coordinate of a view of the scene coordinates |
| Mapping | QPointF mapToScene | The coordinate conversion view a scene coordinates |
2 QGraphicsScene mainly used for scene management graphic item, the item is a container for graphics, there are add, delete function, a variety of management functions of graphical items graphic item.
| Scenes | void setSceneRect（） | A scene set rectangular region |
| Packet | QGraphicsItemGroup* createItemGroup（） | Create a graphic item groups |
| void destroyItemGroup（） | Group released a graphic item | |
| Input focus | QGraphicsItem * focusItem | Returns the current graphic item has focus |
| void clearFocus | Remove the selection focus | |
| bool hasFocus | Whether it has the focus when the view is | |
| Graphic term operation | void addItem（） | Adding a graphical items that have been created |
| void removeItem（） | Delete graphic item | |
| void clear（） | Clear all graphical items | |
| QGraphicesItem* mouseGrabberItem（） |
Returns the graphical items mouse crawl | |
| QList<QGraphicsITEM *>selectedItems（） | Returns a list of graphical items selected | |
| QGraphicsItem *itemAt（） | Get top-level graphical item at a certain location | |
| QList<QGraphicsITEM *> items（） | Returns a list of items in the selected area pattern | |
3 QGraphicsItem pattern is the base class for all classes
Note coordinate mapping
