edu.brook.ascape.view
Class CanvasView

java.lang.Object
  |
  +--java.awt.Component
        |
        +--java.awt.Canvas
              |
              +--edu.brook.ascape.view.CanvasView

Direct Known Subclasses:

BaseCellView, CounterView, SimplexView

public abstract class CanvasView

extends java.awt.Canvas

implements ComponentView

A base class for a canvas that acts as an observer of scapes. Provides for double buffer and notifiation of scape updates.

Since:

1.0

Version:

1.5

See Also:

Serialized Form

Field Summary

protected boolean	awaitingUpdate Has the buffer been modified? Are we waiting for the paint method to update it to the onscreen image?
protected java.awt.Graphics	bufferedGraphics The garphics for double-buffering.
protected java.awt.Image	bufferedImage The image for double-buffering.
protected int	currentUpdate The update currently being drawn.
protected int	drawEveryNUpdates Specifies the number of updates that occur between each draw.
protected ViewFrameBridge	frame The frame this view is displayed in.
protected java.lang.String	name The name of the view.
protected GraphicsRecorder	recorder A recorder for the graphic of this view.
protected boolean	recordNext Are we waiting for a record to occur?
protected Scape	scape The scape being viewed.

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Constructor Summary

CanvasView()
Constructs a canvas view.

CanvasView(java.lang.String name)
Constructs a canvas view.

Method Summary

void	addNotify() Override addNotify to build buffer.
void	addScape(Scape scape) Add a scape to this listener.
void	build() Prepare the component view, once the view's scape has been created.
void	finalize() Attempts to free buffer memory as soon as possible upon canvas destruction.
int	getDrawEveryNUpdates() Returns a name for the view as defined by set name.
GraphicsRecorder	getGraphicsRecorder() Returns a recorder that can be used to record the graphics of this view.
java.lang.String	getName() Returns a name for the view as defined by set name.
java.awt.Dimension	getPreferredSize() Returns default preferred size of width 300 and height 200.
Scape	getScape() Returns the scape this canvas views.
ViewFrameBridge	getViewFrame() Returns the frame this view occupies, null if none.
protected void	initializeBuffer(int width, int height) Initialize the buffer to the supplied width and height.
void	onIterate() Called when scape is iterated.
void	onSetup() Method called when the scape is ready for setup.
void	onStart() Method called when the scape is started.
void	onStop() Method called when the scape is stopped.
void	onUpdate() Called when scape reports an update event.
void	paint(java.awt.Graphics g) Paints the canvas.
void	removeScape(Scape scape) Removes the scape from this listener.
void	scapeUpdated(ScapeEvent scapeEvent) Notifies this view that its scape has been updated.
void	setDrawEveryNUpdates(int drawEveryNUpdates) Sets the name of this view.
void	setGraphicsRecorder(GraphicsRecorder recorder) Sets the recorder that can be used to record the graphics of this view.
void	setName(java.lang.String name) Sets the name of this view.
void	setViewFrame(ViewFrameBridge frame) Sets the frame this view appears in.
java.lang.String	toString() Returns a short description of this view.
void	update(java.awt.Graphics g) Override the Canvas update method so that the canvas is not automatically cleared before painting.
void	updated() Called (typically from paint) when this view has been updated.

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addPropertyChangeListener, addPropertyChangeListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getInputContext, getInputMethodRequests, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getParent, getPeer, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, paramString, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processEvent, processFocusEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFont, setForeground, setLocale, setLocation, setLocation, setSize, setSize, setVisible, show, show, size, transferFocus, validate

Methods inherited from class java.lang.Object

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

Field Detail

bufferedImage

protected transient java.awt.Image bufferedImage

The image for double-buffering.

bufferedGraphics

protected transient java.awt.Graphics bufferedGraphics

The garphics for double-buffering.

scape

protected Scape scape

The scape being viewed.

frame

protected ViewFrameBridge frame

The frame this view is displayed in. Null if this view isn't in a frame.

recorder

protected GraphicsRecorder recorder

A recorder for the graphic of this view. Usually null, unless this view is being recorded.

awaitingUpdate

protected boolean awaitingUpdate

Has the buffer been modified? Are we waiting for the paint method to update it to the onscreen image?

drawEveryNUpdates

protected int drawEveryNUpdates

Specifies the number of updates that occur between each draw. Default is 1, so that every update is drawn.

currentUpdate

protected int currentUpdate

The update currently being drawn.

name

protected java.lang.String name

The name of the view.

recordNext

protected boolean recordNext

Are we waiting for a record to occur?

Constructor Detail

CanvasView

public CanvasView()

Constructs a canvas view.

CanvasView

public CanvasView(java.lang.String name)

Constructs a canvas view.

Parameters:

name - a user relevant name for this view

Method Detail

build

public void build()

Prepare the component view, once the view's scape has been created.

Specified by:

build in interface ComponentView

addNotify

public void addNotify()

Override addNotify to build buffer.

Overrides:

addNotify in class java.awt.Canvas

initializeBuffer

protected void initializeBuffer(int width,
                                int height)

Initialize the buffer to the supplied width and height. Used by scapeUpdated.

Parameters:

width - the width of the buffer

height - the height of the buffer

getPreferredSize

public java.awt.Dimension getPreferredSize()

Returns default preferred size of width 300 and height 200.

Overrides:

getPreferredSize in class java.awt.Component

getScape

public Scape getScape()

Returns the scape this canvas views.

Specified by:

getScape in interface ComponentView

addScape

public void addScape(Scape scape)
              throws java.util.TooManyListenersException

Add a scape to this listener. A listener can be assigned only one scape.

Parameters:

scape - the scape to make this canvas the observer of

Throws:

java.util.TooManyListenersException - on attempt to add a scape when one is allready added

removeScape

public void removeScape(Scape scape)

Removes the scape from this listener. Null expected.

Parameters:

scape - the scape to remove

getViewFrame

public ViewFrameBridge getViewFrame()

Returns the frame this view occupies, null if none.

Specified by:

getViewFrame in interface ComponentView

setViewFrame

public void setViewFrame(ViewFrameBridge frame)

Sets the frame this view appears in.

Specified by:

setViewFrame in interface ComponentView

onIterate

public void onIterate()

Called when scape is iterated.

onSetup

public void onSetup()

Method called when the scape is ready for setup.

onUpdate

public void onUpdate()

Called when scape reports an update event.

onStart

public void onStart()

Method called when the scape is started.

onStop

public void onStop()

Method called when the scape is stopped.

scapeUpdated

public void scapeUpdated(ScapeEvent scapeEvent)

Notifies this view that its scape has been updated. This view then has a chance to update itself, and this super method then notifies the scape that the view itself has been updated. By default, calls the onStart, onUpdate, or onStop method as appropriate, and then notifies scape.

Parameters:

scapeEvent - a scape event update

updated

public void updated()

Called (typically from paint) when this view has been updated. The view calls its observed scape and notifies it that the view has finished updating its state.

getDrawEveryNUpdates

public int getDrawEveryNUpdates()

Returns a name for the view as defined by set name.

setDrawEveryNUpdates

public void setDrawEveryNUpdates(int drawEveryNUpdates)

Sets the name of this view.

Parameters:

name - a user relevant name for this view

getName

public java.lang.String getName()

Returns a name for the view as defined by set name.

Overrides:

getName in class java.awt.Component

setName

public void setName(java.lang.String name)

Sets the name of this view.

Parameters:

name - a user relevant name for this view

Overrides:

setName in class java.awt.Component

getGraphicsRecorder

public GraphicsRecorder getGraphicsRecorder()

Returns a recorder that can be used to record the graphics of this view. If null (default, and typical), there is no recorder for this view.

Specified by:

getGraphicsRecorder in interface ComponentView

setGraphicsRecorder

public void setGraphicsRecorder(GraphicsRecorder recorder)

Sets the recorder that can be used to record the graphics of this view. If null, do not record.

Specified by:

setGraphicsRecorder in interface ComponentView

toString

public java.lang.String toString()

Returns a short description of this view. Sames as name unless overridden.

Overrides:

toString in class java.awt.Component

update

public void update(java.awt.Graphics g)

Override the Canvas update method so that the canvas is not automatically cleared before painting. (Clearing is unneccesary, because we are repainting entire canvas from buffer.)

Overrides:

update in class java.awt.Component

paint

public void paint(java.awt.Graphics g)

Paints the canvas. Ordinarily, you should not do painting here, but into the buffer in the scape updated method. Paint draws the buffer into the canvas. By default, we just copy the buffer in. Override to provide some other kind of behavior, making sure to call this super method, so that the view can report that it has been updated. Otherwise, the whole model will stop, waiting in vain for this view to update.

Specified by:

paint in interface ComponentView

Parameters:

g - the graphics context.

Overrides:

paint in class java.awt.Canvas

finalize

public void finalize()

Attempts to free buffer memory as soon as possible upon canvas destruction.

Overrides:

finalize in class java.lang.Object