com.trolltech.qt.gui
Class QGraphicsView.ViewportUpdateMode

java.lang.Object
  extended by java.lang.Enum
      extended by com.trolltech.qt.gui.QGraphicsView.ViewportUpdateMode
All Implemented Interfaces:
QtEnumerator, java.io.Serializable, java.lang.Comparable
Enclosing class:
QGraphicsView

public static final class QGraphicsView.ViewportUpdateMode
extends java.lang.Enum
implements QtEnumerator

This enum describes how QGraphicsView updates its viewport when the scene contents change or are exposed.

See also:
viewportUpdateMode.

See Also:
Serialized Form

Field Summary
static QGraphicsView.ViewportUpdateMode BoundingRectViewportUpdate
          The bounding rectangle of all changes in the viewport will be redrawn.
static QGraphicsView.ViewportUpdateMode FullViewportUpdate
          When any visible part of the scene changes or is reexposed, QGraphicsView will update the entire viewport.
static QGraphicsView.ViewportUpdateMode MinimalViewportUpdate
          QGraphicsView will determine the minimal viewport region that requires a redraw, minimizing the time spent drawing by avoiding a redraw of areas that have not changed.
static QGraphicsView.ViewportUpdateMode NoViewportUpdate
          QGraphicsView will never update its viewport when the scene changes; the user is expected to control all updates.
static QGraphicsView.ViewportUpdateMode SmartViewportUpdate
          QGraphicsView will attempt to find an optimal update mode by analyzing the areas that require a redraw.
 
Method Summary
static QGraphicsView.ViewportUpdateMode resolve(int value)
          Returns the QGraphicsView$ViewportUpdateMode constant with the specified int.
 int value()
          This function should return an integer value for the enum values of the enumeration that implements this interface.
static QGraphicsView.ViewportUpdateMode valueOf(java.lang.String name)
           
static QGraphicsView.ViewportUpdateMode[] values()
           
 
Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf
 
Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

FullViewportUpdate

public static final QGraphicsView.ViewportUpdateMode FullViewportUpdate
When any visible part of the scene changes or is reexposed, QGraphicsView will update the entire viewport. This approach is fastest when QGraphicsView spends more time figuring out what to draw than it would spend drawing (e.g., when very many small items are repeatedly updated). This is the preferred update mode for viewports that do not support partial updates, such as QGLWidget, and for viewports that need to disable scroll optimization.


MinimalViewportUpdate

public static final QGraphicsView.ViewportUpdateMode MinimalViewportUpdate
QGraphicsView will determine the minimal viewport region that requires a redraw, minimizing the time spent drawing by avoiding a redraw of areas that have not changed. This is QGraphicsView's default mode. Although this approach provides the best performance in general, if there are many small visible changes on the scene, QGraphicsView might end up spending more time finding the minimal approach than it will spend drawing.


SmartViewportUpdate

public static final QGraphicsView.ViewportUpdateMode SmartViewportUpdate
QGraphicsView will attempt to find an optimal update mode by analyzing the areas that require a redraw.


NoViewportUpdate

public static final QGraphicsView.ViewportUpdateMode NoViewportUpdate
QGraphicsView will never update its viewport when the scene changes; the user is expected to control all updates. This mode disables all (potentially slow) item visibility testing in QGraphicsView, and is suitable for scenes that either require a fixed frame rate, or where the viewport is otherwise updated externally.


BoundingRectViewportUpdate

public static final QGraphicsView.ViewportUpdateMode BoundingRectViewportUpdate
The bounding rectangle of all changes in the viewport will be redrawn. This mode has the advantage that QGraphicsView searches only one region for changes, minimizing time spent determining what needs redrawing. The disadvantage is that areas that have not changed also need to be redrawn.

Method Detail

values

public static QGraphicsView.ViewportUpdateMode[] values()

valueOf

public static QGraphicsView.ViewportUpdateMode valueOf(java.lang.String name)

value

public int value()
This function should return an integer value for the enum values of the enumeration that implements this interface.

Specified by:
value in interface QtEnumerator

resolve

public static QGraphicsView.ViewportUpdateMode resolve(int value)
Returns the QGraphicsView$ViewportUpdateMode constant with the specified int.