Class KeyBufferer

java.lang.Object

java.awt.event.MouseAdapter

VASSAL.build.module.map.KeyBufferer

All Implemented Interfaces:

MouseListener, MouseMotionListener, MouseWheelListener, EventListener, Buildable, Drawable

public class KeyBufferer
extends MouseAdapter
implements Buildable, MouseMotionListener, Drawable

Selects and unselects pieces on the map, using the mouse.

The KeyBufferer listens for mouse clicks and drags on its parent Map, determines whether the user is performing a "lasso"/"band-select" or just clicking, draws the selection rectangle where appropriate, and at the end of each relevant mouse action updates the KeyBuffer to maintain the list of which pieces are currently "Selected" in the UI for the parent map.

Its rather misleading name derives from the fact that the selected units are kept in a KeyBuffer, with the idea being that if the player now presses a key, any resulting key command would be applied to all the selected pieces, even though the actual tracking of keys getting pressed and key commands getting applied all happens elsewhere, i.e. in the KeyBuffer class). A more appropriate name might have been e.g. "MouseSelection".

If the user clicks on a GamePiece, that piece is added to the KeyBuffer. draw(Graphics, Map) is responsible for drawing the mouse selection rectangle, and mouseDragged(MouseEvent) is responsible for triggering repaint events as the selection rectangle is moved.

If you are looking for the drag-and-drop handler for dragging pieces on or between maps, instead see PieceMover.

See Also:

• Map.addLocalMouseListener(java.awt.event.MouseListener)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	KeyBufferer.KBDeckVisitor	This "Visitor" dispatcher receives a method call for EVERY piece on the map (one by one), and must filter the pieces based on their presence in the appropriate selection bounds and take the correct action vis-a-vis that piece's selection status.

Field Summary

Fields

Modifier and Type	Field	Description
protected Point	anchor
protected GamePiece	bandSelectPiece
protected Color	color
protected boolean	isLasso
protected Map	map
protected Rectangle	selection
protected int	thickness

Constructor Summary

Constructors

Constructor	Description
KeyBufferer()

Method Summary

Modifier and Type	Method	Description
void	add(Buildable b)	Adds a child component.
void	addTo(Buildable b)	Adds us to our parent map - we register as a mouse listener and a drawable component
void	build(Element e)	Build the object from the XML representation of the Buildable
protected PieceVisitorDispatcher	createDragSelector(boolean selecting, boolean altDown, Rectangle mapsel)	This PieceVisitorDispatcher determines what to do with pieces on the map when the player finished dragging a rectangle to select pieces.
void	dragStarted()	If a drag operation begins, we clear any click-specific information
void	draw(Graphics g, Map map)	Draws our current selection box
boolean	drawAboveCounters()	Selection box is always drawn "above counters'
Element	getBuildElement(Document doc)
boolean	isLasso()
boolean	isMandatory()	Is this component a reqired component within its parent?
boolean	isUnique()	Does this component need to be unique within it's parent?
void	mouseDragged(MouseEvent e)	If the mouse has dragged WHILE a band-select is in progress, sets the new location of the selection rectangle.
void	mouseMoved(MouseEvent e)
void	mousePressed(MouseEvent e)	Process mouse-pressed events.
void	mouseReleased(MouseEvent e)	When the mouse button is released while doing a band-select, we handle updating the selection based on the final size of the selection box.
protected void	repaintSelectionRect()	Initiates a repaint on the selection rectangle

Methods inherited from class java.awt.event.MouseAdapter

mouseClicked, mouseEntered, mouseExited, mouseWheelMoved

Methods inherited from class java.lang.Object

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

Methods inherited from interface VASSAL.build.Buildable

isMovable

Field Details

map

protected Map map

selection

protected Rectangle selection

anchor

protected Point anchor

color

protected Color color

thickness

protected int thickness

bandSelectPiece

protected GamePiece bandSelectPiece

isLasso

protected boolean isLasso

Constructor Details

KeyBufferer

public KeyBufferer()

Method Details

addTo

public void addTo(Buildable b)

Adds us to our parent map - we register as a mouse listener and a drawable component

Specified by:

addTo in interface Buildable

Parameters:

b - Parent map

dragStarted

public void dragStarted()

If a drag operation begins, we clear any click-specific information

add

public void add(Buildable b)

Description copied from interface: Buildable

Adds a child component. Both this method and Buildable.addTo(VASSAL.build.Buildable) are invoked when adding a child to a parent

Specified by:

add in interface Buildable

Parameters:

b - Child to attach to this buildable as a subcomponent

getBuildElement

public Element getBuildElement(Document doc)

Specified by:

getBuildElement in interface Buildable

Parameters:

doc - XML file

Returns:

an XML element from which this component can be built

build

public void build(Element e)

Description copied from interface: Buildable

Build the object from the XML representation of the Buildable

Specified by:

build in interface Buildable

Parameters:

e - the XML element containing the object data

isLasso

public boolean isLasso()

Returns:

true if we've got a valid "selection lasso" drag operation going on (must have breached dragThreshold)

mousePressed

public void mousePressed(MouseEvent e)

Process mouse-pressed events. Depending on what's present where the button became pressed (i.e. movable piece? immovable piece? nothing?) we will determine whether this mouse event will be eligible to be a band-select action.

Specified by:

mousePressed in interface MouseListener

Overrides:

mousePressed in class MouseAdapter

Parameters:

e - Mouse Event

mouseReleased

public void mouseReleased(MouseEvent e)

When the mouse button is released while doing a band-select, we handle updating the selection based on the final size of the selection box.

Specified by:

mouseReleased in interface MouseListener

Overrides:

mouseReleased in class MouseAdapter

Parameters:

e - Mouse event at point of release

createDragSelector

protected PieceVisitorDispatcher createDragSelector(boolean selecting,
 boolean altDown,
 Rectangle mapsel)

This PieceVisitorDispatcher determines what to do with pieces on the map when the player finished dragging a rectangle to select pieces.

Returns:

the "DeckVisitor" used to process each piece.

repaintSelectionRect

protected void repaintSelectionRect()

Initiates a repaint on the selection rectangle

mouseDragged

public void mouseDragged(MouseEvent e)

If the mouse has dragged WHILE a band-select is in progress, sets the new location of the selection rectangle.

Specified by:

mouseDragged in interface MouseMotionListener

Overrides:

mouseDragged in class MouseAdapter

mouseMoved

public void mouseMoved(MouseEvent e)

Specified by:

mouseMoved in interface MouseMotionListener

Overrides:

mouseMoved in class MouseAdapter

draw

public void draw(Graphics g,
 Map map)

Draws our current selection box

Specified by:

draw in interface Drawable

Parameters:

g - graphics object

map - map

drawAboveCounters

public boolean drawAboveCounters()

Selection box is always drawn "above counters'

Specified by:

drawAboveCounters in interface Drawable

Returns:

true

isMandatory

public boolean isMandatory()

Description copied from interface: Buildable

Is this component a reqired component within its parent?

Specified by:

isMandatory in interface Buildable

Returns:

true if component is mandatory

isUnique

public boolean isUnique()

Description copied from interface: Buildable

Does this component need to be unique within it's parent?

Specified by:

isUnique in interface Buildable

Returns: