ICanvasObjectDescriptor (yFiles-for-JavaFX-Complete-3.0 API)

All Known Implementing Classes:

DefaultPortCandidateDescriptor
```
public interface ICanvasObjectDescriptor
```
Central interface used by the CanvasControl to render elements from the scene graph.
Implementations will be queried using the user object obtained from UserObject for the corresponding implementations of the various aspects of the user object. Implementations of this interface need to be provided by the application programmer to ICanvasObjectGroup's ICanvasObjectGroup.addChild(Object, ICanvasObjectDescriptor) method.

See Also:

CanvasObjectDescriptors

Field Summary

Fields
Modifier and Type	Field and Description
`static ICanvasObjectDescriptor`	`ALWAYS_DIRTY_INSTANCE` An implementation that tries to cast the user object to the required interface.
`static ICanvasObjectDescriptor`	`ALWAYS_DIRTY_LOOKUP` An implementation that tries to lookup the instance from the user object if it is an `ILookup`.
`static ICanvasObjectDescriptor`	`DYNAMIC_DIRTY_INSTANCE` An implementation that tries to cast the user object to the required interface.
`static ICanvasObjectDescriptor`	`DYNAMIC_DIRTY_LOOKUP` An implementation that tries to lookup the instance from the user object if it is an `ILookup`.
`static ICanvasObjectDescriptor`	`VISUAL` An implementation that will cast the `UserObject` to `VISUAL` and use that to insert into the scene graph.
`static ICanvasObjectDescriptor`	`VOID` An implementation that returns an `ICanvasObjectDescriptor` that does nothing.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`IBoundsProvider`	`getBoundsProvider(Object forUserObject)` Returns an implementation of `IBoundsProvider` that can determine the visible bounds of the rendering of the user object.
`IHitTestable`	`getHitTestable(Object forUserObject)` Returns an implementation of `IHitTestable` that can determine whether the rendering of the user object has been hit at a given coordinate.
`IVisibilityTestable`	`getVisibilityTestable(Object forUserObject)` Returns an implementation of `IVisibilityTestable` that can determine if the rendering of the user object would be visible in a given context.
`IVisualCreator`	`getVisualCreator(Object forUserObject)` Returns an implementation of `IVisualCreator` that will create the `Node` tree for the user object.
`boolean`	`isDirty(ICanvasContext context, ICanvasObject canvasObject)` Determines whether the given canvas object is deemed dirty and needs updating.

- Field Detail
  - ALWAYS_DIRTY_INSTANCE
```
static final ICanvasObjectDescriptor ALWAYS_DIRTY_INSTANCE
```
    An implementation that tries to cast the user object to the required interface.
    This implementation will treat always update the Visual and will effectively ignore the Dirty flag.
  - ALWAYS_DIRTY_LOOKUP
```
static final ICanvasObjectDescriptor ALWAYS_DIRTY_LOOKUP
```
    An implementation that tries to lookup the instance from the user object if it is an ILookup.
    This implementation will treat always update the Visual and will effectively ignore the Dirty flag.
  - DYNAMIC_DIRTY_INSTANCE
```
static final ICanvasObjectDescriptor DYNAMIC_DIRTY_INSTANCE
```
    An implementation that tries to cast the user object to the required interface.
    This implementation will respect the Dirty flag.
  - DYNAMIC_DIRTY_LOOKUP
```
static final ICanvasObjectDescriptor DYNAMIC_DIRTY_LOOKUP
```
    An implementation that tries to lookup the instance from the user object if it is an ILookup.
    This implementation will respect the Dirty flag.
  - VISUAL
```
static final ICanvasObjectDescriptor VISUAL
```
    An implementation that will cast the UserObject to VISUAL and use that to insert into the scene graph.
  - VOID
```
static final ICanvasObjectDescriptor VOID
```
    An implementation that returns an ICanvasObjectDescriptor that does nothing.
- Method Detail
  - getBoundsProvider
```
IBoundsProvider getBoundsProvider(Object forUserObject)
```
    Returns an implementation of IBoundsProvider that can determine the visible bounds of the rendering of the user object.
    This method may always return the same instance. By contract, clients will not cache instances returned, but will always call this method before the methods on the instance will be called. This contract enables the use of the fly-weight design pattern. Implementations of this class can always return the same instance and reconfigure this instance upon each call to this method.
    
    Parameters:
    
    forUserObject - the user object to query the bounds for
    
    Returns:
    
    an implementation or null if the bounds are not known, in which case the bounds are treated as infinite
  - getHitTestable
```
IHitTestable getHitTestable(Object forUserObject)
```
    Returns an implementation of IHitTestable that can determine whether the rendering of the user object has been hit at a given coordinate.
    This method may always return the same instance. By contract, clients will not cache instances returned, but will always call this method before the methods on the instance will be called. This contract enables the use of the fly-weight design pattern. Implementations of this class can always return the same instance and reconfigure this instance upon each call to this method.
    
    Parameters:
    
    forUserObject - the user object to do the hit testing for
    
    Returns:
    
    an implementation or null if the rendering cannot be hit tested
  - getVisibilityTestable
```
IVisibilityTestable getVisibilityTestable(Object forUserObject)
```
    Returns an implementation of IVisibilityTestable that can determine if the rendering of the user object would be visible in a given context.
    This method may always return the same instance. By contract clients will not cache instances returned but will always call this method before the methods on the instance will be called. This contract enables the use of the fly-weight design pattern. Implementations of this class can always return the same instance and reconfigure this instance upon each call to this method.
    
    Parameters:
    
    forUserObject - the user object to query the bounds for
    
    Returns:
    
    an implementation or null if the bounds are not known, in which case the bounds are treated as infinite
  - getVisualCreator
```
IVisualCreator getVisualCreator(Object forUserObject)
```
    Returns an implementation of IVisualCreator that will create the Node tree for the user object.
    This method may always return the same instance. By contract, clients will not cache instances returned, but will always call this method before the methods on the instance will be called. This contract enables the use of the fly-weight design pattern. Implementations of this class can always return the same instance and reconfigure this instance upon each call to this method.
    
    Parameters:
    
    forUserObject - the user object to create a Visual for
    
    Returns:
    
    an implementation or null if nothing shall be rendered
  - isDirty
```
boolean isDirty(ICanvasContext context,
                ICanvasObject canvasObject)
```
    Determines whether the given canvas object is deemed dirty and needs updating.
    
    Parameters:
    
    context - The context that will be used for the update.
    
    canvasObject - The object to check.
    
    Returns:
    
    Whether an update is needed.

Interface ICanvasObjectDescriptor

Field Summary

Method Summary

Field Detail

ALWAYS_DIRTY_INSTANCE

ALWAYS_DIRTY_LOOKUP

DYNAMIC_DIRTY_INSTANCE

DYNAMIC_DIRTY_LOOKUP

VISUAL

VOID

Method Detail

getBoundsProvider

getHitTestable

getVisibilityTestable

getVisualCreator

isDirty