Modifying geometric properties of objects

> > > > >

For every operation that leads to a modification of the bounding box of a graphic object, you must use the applyToObject method of the IlvManager class. As this method notifies the manager of the modification of the bounding box, you never directly call the moveObject and reshapeObject methods of IlvGraphic :

void moveObject(IlvGraphic obj, float x, float y, boolean redraw)

void reshapeObject(IlvGraphic obj, IlvRect newrect, boolean redraw)

For these basic operations, the manager has methods that call applyToObject for you:

Example: Moving an object

The following code gets a reference to an object named test from the manager. If the object exists, it is moved to the point (10, 20) and redrawn (fourth parameter set to true ).

IlvGraphic object = manager.getObject("test");
if (object != null) 
  manager.moveObject(object, 10, 20, true);

The moveObject method is equivalent to the following code:

manager.applyToObject(object,
  new IlvApplyObject()
  {
   public void apply(IlvGraphic obj, Object arg){
     IlvPoint p = (IlvPoint) arg;
     obj.move(p.x, p.y);
   }
  }, 
  new IlvPoint(10,20), true);

This code calls the applyToObject method with object as a parameter and an anonymous class that implements the IlvApplyObject interface. The arg parameter is an IlvPoint object that gives the new location of the object.

The method applyToObject is defined in the IlvGraphicBag interface, so you may call applyToObject directly from a graphic object using:

obj.getGraphicBag().applyToObject(obj, ...);

Modifying multiple graphic objects

To apply an operation to many graphic objects repeatedly, call:

void applyToObjects(IlvGraphicVector vector,
                      IlvApplyObject f,
                      Object arg,
                      boolean redraw)

This applies the operation specified by the IlvApplyObject f to each graphic object contained in the input vector.

To apply complex operations that affect the bounding box of many graphic objects to many objects once only, call:

void applyToObjects(IlvGraphicVector vector,
                      IlvApplyObjects f,
                      Object arg,
                      boolean redraw)

This applies the operation specified by the IlvApplyObjects f once only. This is useful for complex operations that affect the bounding box of many objects.

Note

The applyToObjects method is overloaded. In the first example it takes an IlvApplyObject object as a parameter. In the second example it takes an IlvApplyObjects (plural) object as a parameter.

Current section

Managing graphic objects