java.lang.Object | +--java.awt.Component | +--java.awt.Canvas
Unsafe: A Canvas component represents a blank rectangular
area of the screen onto which the application can draw or from
which the application can trap input events from the user.
An application must subclass the Canvas class in
order to get useful functionality such as creating a custom
component. The paint method must be overridden
in order to perform custom graphics on the canvas.
accessibleContext, actionListenerK, adjustmentListenerK, appContext, background, BOTTOM_ALIGNMENT, bufferStrategy, CENTER_ALIGNMENT, componentListener, componentListenerK, componentOrientation, containerListenerK, cursor, dropTarget, enabled, eventMask, focusListener, focusListenerK, focusTraversalKeys, font, foreground, graphicsConfig, height, hierarchyBoundsListener, hierarchyBoundsListenerK, hierarchyListener, hierarchyListenerK, ignoreRepaint, incRate, inputMethodListener, inputMethodListenerK, isInc, isPacked, itemListenerK, keyListener, keyListenerK, LEFT_ALIGNMENT, locale, LOCK, metrics, minSize, mouseListener, mouseListenerK, mouseMotionListener, mouseMotionListenerK, mouseWheelListener, mouseWheelListenerK, newEventsOnly, ownedWindowK, parent, peer, peerFont, popups, prefSize, RIGHT_ALIGNMENT, textListenerK, TOP_ALIGNMENT, valid, visible, width, windowClosingException, windowFocusListenerK, windowListenerK, windowStateListenerK, x, y
Canvas()
Canvas(GraphicsConfiguration config)
void
createBufferStrategy(int numBuffers)
void
createBufferStrategy(int numBuffers,
BufferCapabilities caps)
AccessibleContext
getAccessibleContext()
java.awt.image.BufferStrategy
getBufferStrategy()
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, adjustListeningChildrenOnParent, applyComponentOrientation, areFocusTraversalKeysSet, areInputMethodsEnabled, autoProcessMouseWheel, autoTransferFocus, bounds, checkGD, checkImage, checkImage, checkWindowClosingException, clearCurrentFocusCycleRootOnHide, clearMostRecentFocusOwnerOnHide, coalesceEvents, contains, contains, containsFocus, countHierarchyMembers, createChildHierarchyEvents, createHierarchyEvents, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, dispatchEventImpl, dispatchMouseWheelToAncestor, doLayout, enable, enable, enableEvents, enableInputMethods, eventEnabled, eventTypeEnabled, firePropertyChange, firePropertyChange, firePropertyChange, getAccessibleIndexInParent, getAccessibleStateSet, getAlignmentX, getAlignmentY, getBackBuffer, getBackground, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys_NoIDCheck, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont_NoClientCode, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getListeners, getLocale, getLocation, getLocation, getLocationOnScreen_NoTreeLock, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMouseWheelListeners, getName, getNativeContainer, getParent_NoClientCode, getParent, getPeer, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getToolkitImpl, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, initializeFocusTraversalKeys, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isEnabledImpl, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFocusTraversableOverridden, isFontSet, isForegroundSet, isLightweight, isOpaque, isRecursivelyVisible, isShowing, isValid, isVisible, iterate, keyDown, keyUp, layout, lightweightPaint, lightweightPrint, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, nextFocusHelper, numListening, paintAll, paintHeavyweightComponents, paramString, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, printHeavyweightComponents, processComponentEvent, processEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusHelper, requestFocusInWindow, requestFocusInWindow, resetGC, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys_NoIDCheck, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setGCFromPeer, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocus, transferFocusBackward, transferFocusUpCycle, updateCursorImmediately, validate
private static final String base
private static int nameCounter
private static final long serialVersionUID
public Canvas()
public Canvas(GraphicsConfiguration config)
config - a reference to a GraphicsConfiguration object.GraphicsConfigurationString constructComponentName()
constructComponentName in class Componentpublic void addNotify()
java.awt.Toolkit#createCanvas(java.awt.Canvas),
java.awt.Component#getToolkit()public void paint(Graphics g)
Most applications that subclass Canvas should
override this method in order to perform some useful operation
(typically, custom painting of the canvas).
The default operation is simply to clear the canvas.
Applications that override this method need not call
super.paint(g).
g - the specified Graphics contextupdate(Graphics),
Component.paint(Graphics)public void update(Graphics g)
This method is called in response to a call to repaint.
The canvas is first cleared by filling it with the background
color, and then completely redrawn by calling this canvas's
paint method.
Note: applications that override this method should either call
super.update(g) or incorporate the functionality described
above into their own code.
g - the specified Graphics contextpaint(Graphics),
Component.update(Graphics)boolean postsOldMouseEvents()
postsOldMouseEvents in class Componentpublic void createBufferStrategy(int numBuffers)
BufferStrategy
with that number of buffers.
A page-flipping strategy is attempted first, then a blitting strategy
using accelerated buffers. Finally, an unaccelerated blitting
strategy is used.
Each time this method is called, the existing buffer strategy for this component is discarded.
createBufferStrategy in class ComponentnumBuffers - number of buffers to create, including the front bufferComponent.isDisplayable(),
getBufferStrategy()public void createBufferStrategy(int numBuffers, BufferCapabilities caps) throws AWTException
Each time this method is called, the existing buffer strategy for this component is discarded.
createBufferStrategy in class ComponentnumBuffers - number of buffers to createcaps - the required capabilities for creating the buffer strategy;
cannot be null
AWTExceptiongetBufferStrategy()public java.awt.image.BufferStrategy getBufferStrategy()
getBufferStrategy in class ComponentcreateBufferStrategy(int)public AccessibleContext getAccessibleContext()
getAccessibleContext in interface AccessiblegetAccessibleContext in class Component