public class Canvas extends Component implements Accessible
Canvas
组件是一个空白的矩形区域的屏幕上的应用程序可以绘制或从应用程序可以捕获用户输入事件。
应用程序必须子类的Canvas
阶级为了得到有用的功能,如创建一个自定义组件。的paint
方法必须被重写以帆布上执行自定义的图形。
Modifier and Type | Class and Description |
---|---|
protected class |
Canvas.AccessibleAWTCanvas
这个类实现了对
Canvas 类可访问性支持。
|
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
Constructor and Description |
---|
Canvas()
构建一个新的画布。
|
Canvas(GraphicsConfiguration config)
构建了一种新的画布了graphicsconfiguration对象。
|
Modifier and Type | Method and Description |
---|---|
void |
addNotify()
创建画布的对等点。
|
void |
createBufferStrategy(int numBuffers)
为这个组件创建一个新的多缓冲策略。
|
void |
createBufferStrategy(int numBuffers, BufferCapabilities caps)
为这个组件创建一个新的策略,该组件具有所需的缓冲能力。
|
AccessibleContext |
getAccessibleContext()
获取与此相关的accessiblecontext帆布。
|
BufferStrategy |
getBufferStrategy()
该组件使用的
BufferStrategy 返回。
|
void |
paint(Graphics g)
油漆这画布。
|
void |
update(Graphics g)
更新这个画布。
|
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, 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, 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, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, validate
public Canvas()
public Canvas(GraphicsConfiguration config)
config
-参考一graphicsconfiguration对象。
GraphicsConfiguration
public void addNotify()
addNotify
方法重写,继承类
Component
Toolkit.createCanvas(java.awt.Canvas)
,
Component.getToolkit()
public void paint(Graphics g)
大多数应用Canvas
类应重写此方法以执行一些有用的操作(通常,风俗画的画布)。默认操作是简单地清除画布。重写此方法的应用程序不需要调用超级。
paint
方法重写,继承类
Component
g
-指定的图形上下文
update(Graphics)
,
Component.paint(Graphics)
public void update(Graphics g)
这种方法被称为响应号召repaint
。画布是先用背景色填充它清除,然后通过调用这画布的paint
方法完全重画。注:重写此方法的应用程序应该调用超级。更新(G)或将上面所述的功能加入到自己的代码中。
update
方法重写,继承类
Component
g
-指定的图形上下文
paint(Graphics)
,
Component.update(Graphics)
public void createBufferStrategy(int numBuffers)
BufferStrategy
。一个页面翻转的策略是首先,然后一个位图使用加速缓冲策略。最后,一个加速blitting策略应用。
每次这种方法被调用时,这个组件的现有缓冲策略将被丢弃。
numBuffers
-数量的缓冲区的创建,包括前台缓冲区
IllegalArgumentException
-如果numbuffers小于1。
IllegalStateException
如果组件不显示
Component.isDisplayable()
,
getBufferStrategy()
public void createBufferStrategy(int numBuffers, BufferCapabilities caps) throws AWTException
每次这种方法被调用时,这个组件的现有缓冲策略将被丢弃。
numBuffers
-缓冲区数目
caps
-所需能力创建缓存策略;不能
null
AWTException
如果能力提供不能支持或满足;这可能发生,例如,如果没有足够的记忆加速目前可用的,或者如果页面翻转是不可能指定。
IllegalArgumentException
-如果numbuffers小于1,或者是
null
帽
getBufferStrategy()
public BufferStrategy getBufferStrategy()
BufferStrategy
返回。这个方法如果
BufferStrategy
尚未创建或已设置返回null。
createBufferStrategy(int)
public AccessibleContext getAccessibleContext()
getAccessibleContext
接口
Accessible
getAccessibleContext
方法重写,继承类
Component
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2014, Oracle and/or its affiliates. All rights reserved.