diva.canvas.interactor
Class SelectionInteractor

java.lang.Object
  diva.canvas.interactor.AbstractInteractor
      diva.canvas.interactor.CompositeInteractor
          diva.canvas.interactor.SelectionInteractor

All Implemented Interfaces:

LayerListener, LayerMotionListener, Interactor, java.util.EventListener

Direct Known Subclasses:

EdgeInteractor, NodeInteractor

public class SelectionInteractor
extends CompositeInteractor

A SelectionInteractor is attached to an object that can be put into and out of a selection. Associated with each such role is a selection model, which is the selection that figures are added to or removed from. When a mouse pressed event has occurred, all figures associated with the same SelectionModel will be unselected before the new one is selected. So, to make sure only one figure is selected at a time, do this: SelectionModel m = new SelectionModel(); SelectionInteractor s1 = new SelectionInteractor(m); SelectionInteractor s2 = new SelectionInteractor(m);

When an item is selected, events are then forwarded to other interactors. If, however, the clicked-on figure has just been removed from the figure, do not forward events.

Version:

$Id: SelectionInteractor.java 53042 2009-04-10 20:31:21Z cxh $

Author:

John Reekie

Field Summary

private SelectionRenderer	_renderer The selection renderer
private SelectionModel	_selection The selection model
private MouseFilter	_selectionFilter The mouse filter for selecting items
private MouseFilter	_toggleFilter The mouse filter for toggling items

Constructor Summary

SelectionInteractor()
Create a new SelectionInteractor with a default selection model and a default selection renderer.

SelectionInteractor(SelectionModel model)
Create a new SelectionInteractor with the given selection model and a null selection renderer.

Method Summary

boolean	accept(LayerEvent e) Accept an event if it will be accepted by the selection filters.
MouseFilter	getSelectionFilter() Get the mouse filter that controls when this selection filter is activated.
SelectionModel	getSelectionModel() Get the selection model
SelectionRenderer	getSelectionRenderer() Get the selection renderer
MouseFilter	getToggleFilter() Get the mouse filter that controls the toggling of selections
static boolean	isSelected(LayerEvent e) Given a mouse event, check that the figure it contains as its event source is selected.
void	mousePressed(LayerEvent event) Handle a mouse press event.
void	setConsuming(boolean flag) Set the consuming flag of this interactor.
void	setPrototypeDecorator(FigureDecorator decorator) Set the prototype decorator for selected figures.
void	setSelectionFilter(MouseFilter f) Set the mouse filter that controls when this selection filter is activated.
void	setSelectionManipulator(Manipulator manipulator) Deprecated. Use setPrototypeDecorator instead
void	setSelectionModel(SelectionModel model) Set the selection model.
void	setSelectionRenderer(SelectionRenderer r) Set the selection renderer.
void	setToggleFilter(MouseFilter f) Set the mouse filter that controls the toggling of selections.

Methods inherited from class diva.canvas.interactor.CompositeInteractor

addInteractor, interactors, isMotionEnabled, mouseDragged, mouseEntered, mouseExited, mouseMoved, mouseReleased, removeInteractor

Methods inherited from class diva.canvas.interactor.AbstractInteractor

getMouseFilter, isConsuming, isEnabled, mouseClicked, setEnabled, setMotionEnabled, setMouseFilter

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_selection

private SelectionModel _selection

The selection model

_renderer

private SelectionRenderer _renderer

The selection renderer

_selectionFilter

private MouseFilter _selectionFilter

The mouse filter for selecting items

_toggleFilter

private MouseFilter _toggleFilter

The mouse filter for toggling items

Constructor Detail

SelectionInteractor

public SelectionInteractor()

Create a new SelectionInteractor with a default selection model and a default selection renderer.

SelectionInteractor

public SelectionInteractor(SelectionModel model)

Create a new SelectionInteractor with the given selection model and a null selection renderer.

Method Detail

accept

public boolean accept(LayerEvent e)

Accept an event if it will be accepted by the selection filters.

Specified by:

accept in interface Interactor

Overrides:

accept in class CompositeInteractor

getSelectionFilter

public MouseFilter getSelectionFilter()

Get the mouse filter that controls when this selection filter is activated.

getSelectionModel

public SelectionModel getSelectionModel()

Get the selection model

getSelectionRenderer

public SelectionRenderer getSelectionRenderer()

Get the selection renderer

getToggleFilter

public MouseFilter getToggleFilter()

Get the mouse filter that controls the toggling of selections

isSelected

public static boolean isSelected(LayerEvent e)

Given a mouse event, check that the figure it contains as its event source is selected. By selected, we mean that figure has a SelectionInteractor as its interactor, and that the figure is in the SelectionModel of that interactor.

mousePressed

public void mousePressed(LayerEvent event)

Handle a mouse press event. Add or remove the clicked-on item to or from the selection. If it's still in the selection, pass the event to the superclass to handle.

Specified by:

mousePressed in interface LayerListener

Overrides:

mousePressed in class CompositeInteractor

setConsuming

public void setConsuming(boolean flag)

Set the consuming flag of this interactor. This flag is a little more complicated than in simple interactors: if not set, then the event is consumed only if the clicked-on figure is added to or removed from the selection. Otherwise it is not consumed. If the flag is set, then the event is always consumed, thus making it effectively "opaque" to events.

Note that the behaviour when the flag is false is the desired behaviour when building panes that have an interactor attached to the background. That way, the event passes through to the background if a figure is hit on but the selection interactor's filters are set up to ignore that particular event.

There is a third possibility, which is not supported: never consume events. There is no way to do this currently, as the other two behaviors seemed more likely to be useful. (Also, that behaviour is harder to implement because of interaction with the superclass.)

Overrides:

setConsuming in class AbstractInteractor

setSelectionModel

public void setSelectionModel(SelectionModel model)

Set the selection model. The existing selection model is cleared first.

setSelectionFilter

public void setSelectionFilter(MouseFilter f)

Set the mouse filter that controls when this selection filter is activated.

setPrototypeDecorator

public void setPrototypeDecorator(FigureDecorator decorator)

Set the prototype decorator for selected figures. Selected figures will have a copy of this decorator wrapped around them. This call is a convenience short-hand for

    this.setSelectionRenderer(new BasicSelectionRenderer(decorator);
 

This method nullifies any previous renderers set with setSelectionRenderer();

setSelectionManipulator

public void setSelectionManipulator(Manipulator manipulator)

Deprecated. Use setPrototypeDecorator instead

Set the prototype selection manipulator. Selected figures will have a copy of this manipulator wrapped around them. This method nullifies any previous renderers set with setSelectionRenderer();

setSelectionRenderer

public void setSelectionRenderer(SelectionRenderer r)

Set the selection renderer. The object is not used in this class, but can be set here so that other objects that need to render selected objects know how to do so.

setToggleFilter

public void setToggleFilter(MouseFilter f)

Set the mouse filter that controls the toggling of selections.