gnu.awt.xlib

Class XCanvasPeer

Implemented Interfaces:
CanvasPeer, ComponentPeer
Known Direct Subclasses:
XFramePeer, XPanelPeer

public class XCanvasPeer
extends Object
implements CanvasPeer

Field Summary

//
temporaryWindowwindow

Constructor Summary

XCanvasPeer(Component component)

Method Summary

boolean
canDetermineObscurity()
Returns true if this component peer can determine if the component has been obscured, false otherwise.
void
cancelPendingPaint(int x, int y, int width, int height)
int
checkImage(Image img, int width, int height, ImageObserver o)
Returns the construction status of the specified image.
void
coalescePaintEvent(PaintEvent e)
Coalesces the specified paint event.
void
createBuffers(int x, BufferCapabilities capabilities)
Create a number of image buffers that implement a buffering strategy according to the given capabilities.
Image
createImage(int width, int height)
Creates an empty image with the specified width and height.
Image
createImage(ImageProducer prod)
Creates an image by starting the specified image producer.
VolatileImage
createVolatileImage(int width, int height)
A convenience method that creates a volatile image.
void
destroyBuffers()
Destroy the resources created by createBuffers.
void
disable()
Disables the component.
void
dispose()
Disposes the component peer.
void
enable()
Enables the component.
protected void
ensureFlush()
void
flip(BufferCapabilities.FlipContents contents)
Perform a page flip, leaving the contents of the back buffer in the specified state.
Image
getBackBuffer()
Return the back buffer of this component.
Rectangle
getBounds()
ColorModel
getColorModel()
Returns the color model of the component.
Component
getComponent()
FontMetrics
getFontMetrics(Font f)
Returns the font metrics for the specified font.
Graphics
getGraphics()
Returns a Graphics object suitable for drawing on this component.
GraphicsConfiguration
getGraphicsConfiguration()
Get the graphics configuration of the component.
Point
getLocationOnScreen()
Returns the location of this component in screen coordinates.
Dimension
getMinimumSize()
Returns the minimum size for the component.
Dimension
getPreferredSize()
Returns the preferred size for the component.
Toolkit
getToolkit()
Returns the toolkit that created this peer.
void
handleEvent(AWTEvent event)
Handles the given event.
boolean
handlesWheelScrolling()
Returns true, if this component can handle wheel scrolling, false otherwise.
void
hide()
Makes the component invisible.
boolean
isFocusTraversable()
Returns true if the component can receive keyboard input focus.
boolean
isFocusable()
Returns true if the component can receive keyboard input focus.
boolean
isObscured()
Returns true if this component has been obscured, false otherwise.
boolean
isReparentSupported()
boolean
isRestackSupported()
void
layout()
Dimension
minimumSize()
Returns the minimum size for the component.
void
paint(Graphics gfx)
Dimension
preferredSize()
Returns the preferred size for the component.
boolean
prepareImage(Image img, int width, int height, ImageObserver o)
Prepares an image for rendering on this component.
void
print(Graphics graphics)
void
repaint(long tm, int x, int y, int w, int h)
Repaints the specified rectangle of this component.
void
reparent(ContainerPeer parent)
void
requestFocus()
Requests that this component receives the focus.
boolean
requestFocus(Component source, boolean b1, boolean b2, long x)
Requests that this component receives the focus.
boolean
requestFocus(Component source, boolean b1, boolean b2, long x, CausedFocusEvent.Cause cause)
Requests the focus on the component.
void
reshape(int x, int y, int width, int height)
Notifies the peer that the bounds of this component have changed.
void
restack()
void
setBackground(Color color)
Sets the background color of the component.
void
setBounds(int x, int y, int width, int height)
Notifies the peer that the bounds of this component have changed.
void
setBounds(int x, int y, int width, int height, int z)
void
setCursor(Cursor cursor)
Sets the cursor of the component.
void
setEnabled(boolean enabled)
Sets the enabled/disabled state of this component.
void
setEventMask(long eventMask)
Part of an older API, no longer needed.
void
setFont(Font font)
Sets the font of the component.
void
setForeground(Color color)
Sets the foreground color of the component.
void
setVisible(boolean visible)
Sets the visibility state of the component.
void
show()
Makes the component visible.
void
updateCursorImmediately()
Updates the cursor.

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

temporaryWindowwindow

public // temporaryWindowwindow

Constructor Details

XCanvasPeer

public XCanvasPeer(Component component)

Method Details

canDetermineObscurity

public boolean canDetermineObscurity()
Returns true if this component peer can determine if the component has been obscured, false otherwise.
Specified by:
canDetermineObscurity in interface ComponentPeer
Returns:
true if this component peer can determine if the component has been obscured, false otherwise

cancelPendingPaint

public void cancelPendingPaint(int x,
                               int y,
                               int width,
                               int height)
Since:
1.5

checkImage

public int checkImage(Image img,
                      int width,
                      int height,
                      ImageObserver o)
Returns the construction status of the specified image. This is called by Component.checkImage(Image,int,int,ImageObserver).
Specified by:
checkImage in interface ComponentPeer
Parameters:
img - the image
width - the width of the image
height - the height of the image
Returns:
a bitwise ORed set of ImageObserver flags

coalescePaintEvent

public void coalescePaintEvent(PaintEvent e)
Coalesces the specified paint event.
Specified by:
coalescePaintEvent in interface ComponentPeer
Parameters:
e - the paint event

createBuffers

public void createBuffers(int x,
                          BufferCapabilities capabilities)
            throws AWTException
Create a number of image buffers that implement a buffering strategy according to the given capabilities.
Specified by:
createBuffers in interface ComponentPeer
Parameters:
Throws:
AWTException - if the specified buffering strategy is not implemented
Since:
1.2

createImage

public Image createImage(int width,
                         int height)
Creates an empty image with the specified width and height.
Specified by:
createImage in interface ComponentPeer
Parameters:
width - the width of the image to be created
height - the height of the image to be created
Returns:
the created image

createImage

public Image createImage(ImageProducer prod)
Creates an image by starting the specified image producer. This is called by Component.createImage(ImageProducer).
Specified by:
createImage in interface ComponentPeer
Parameters:
prod - the image producer to be used to create the image
Returns:
the created image

createVolatileImage

public VolatileImage createVolatileImage(int width,
                                         int height)
A convenience method that creates a volatile image. The volatile image is created on the screen device on which this component is displayed, in the device's current graphics configuration.
Specified by:
createVolatileImage in interface ComponentPeer
Parameters:
width - width of the image
height - height of the image
Since:
1.2
See Also:
VolatileImage

destroyBuffers

public void destroyBuffers()
Destroy the resources created by createBuffers.
Specified by:
destroyBuffers in interface ComponentPeer
Since:
1.2

disable

public void disable()
Disables the component. This is called by Component.disable().
Specified by:
disable in interface ComponentPeer

dispose

public void dispose()
Disposes the component peer. This should release all resources held by the peer. This is called when the component is no longer in use.
Specified by:
dispose in interface ComponentPeer

enable

public void enable()
Enables the component. This is called by Component.enable().
Specified by:
enable in interface ComponentPeer

ensureFlush

protected void ensureFlush()

flip

public void flip(BufferCapabilities.FlipContents contents)
Perform a page flip, leaving the contents of the back buffer in the specified state.
Specified by:
flip in interface ComponentPeer
Parameters:
contents - the state in which to leave the back buffer
Since:
1.2

getBackBuffer

public Image getBackBuffer()
Return the back buffer of this component.
Specified by:
getBackBuffer in interface ComponentPeer
Returns:
the back buffer of this component.
Since:
1.2

getBounds

public Rectangle getBounds()
Specified by:
getBounds in interface ComponentPeer
Since:
1.5

getColorModel

public ColorModel getColorModel()
Returns the color model of the component. This is currently not used.
Specified by:
getColorModel in interface ComponentPeer
Returns:
the color model of the component

getComponent

public Component getComponent()

getFontMetrics

public FontMetrics getFontMetrics(Font f)
Returns the font metrics for the specified font. This is called by Component.getFontMetrics(Font).
Specified by:
getFontMetrics in interface ComponentPeer
Parameters:
f - the font for which to query the font metrics
Returns:
the font metrics for the specified font

getGraphics

public Graphics getGraphics()
Returns a Graphics object suitable for drawing on this component. This is called by Component.getGraphics().
Specified by:
getGraphics in interface ComponentPeer
Returns:
a graphics object suitable for drawing on this component

getGraphicsConfiguration

public GraphicsConfiguration getGraphicsConfiguration()
Get the graphics configuration of the component. The color model of the component can be derived from the configuration.
Specified by:
getGraphicsConfiguration in interface ComponentPeer
Returns:
the graphics configuration of the component

getLocationOnScreen

public Point getLocationOnScreen()
Returns the location of this component in screen coordinates. This is called by Component.getLocationOnScreen().
Specified by:
getLocationOnScreen in interface ComponentPeer
Returns:
the location of this component in screen coordinates

getMinimumSize

public Dimension getMinimumSize()
Returns the minimum size for the component. This is called by Component.getMinimumSize().
Specified by:
getMinimumSize in interface ComponentPeer
Returns:
the minimum size for the component

getPreferredSize

public Dimension getPreferredSize()
Returns the preferred size for the component. This is called by Component.getPreferredSize().
Specified by:
getPreferredSize in interface ComponentPeer
Returns:
the preferred size for the component

getToolkit

public Toolkit getToolkit()
Returns the toolkit that created this peer.
Specified by:
getToolkit in interface ComponentPeer
Returns:
the toolkit that created this peer

handleEvent

public void handleEvent(AWTEvent event)
Handles the given event. This is called from Component.dispatchEvent(AWTEvent) to give the peer a chance to react to events for the component.
Specified by:
handleEvent in interface ComponentPeer
Parameters:

handlesWheelScrolling

public boolean handlesWheelScrolling()
Returns true, if this component can handle wheel scrolling, false otherwise.
Specified by:
handlesWheelScrolling in interface ComponentPeer
Returns:
true, if this component can handle wheel scrolling, false otherwise

hide

public void hide()
Makes the component invisible. This is called from Component.hide().
Specified by:
hide in interface ComponentPeer

isFocusTraversable

public boolean isFocusTraversable()
Returns true if the component can receive keyboard input focus. This is called from Component.isFocusTraversable().
Specified by:
isFocusTraversable in interface ComponentPeer

isFocusable

public boolean isFocusable()
Returns true if the component can receive keyboard input focus. This is called from Component.isFocusable().
Specified by:
isFocusable in interface ComponentPeer

isObscured

public boolean isObscured()
Returns true if this component has been obscured, false otherwise. This will only work if ComponentPeer.canDetermineObscurity() also returns true.
Specified by:
isObscured in interface ComponentPeer
Returns:
true if this component has been obscured, false otherwise.

isReparentSupported

public boolean isReparentSupported()
Specified by:
isReparentSupported in interface ComponentPeer
Since:
1.5

isRestackSupported

public boolean isRestackSupported()
Since:
1.5

layout

public void layout()
Specified by:
layout in interface ComponentPeer
Since:
1.5

minimumSize

public Dimension minimumSize()
Returns the minimum size for the component. This is called by Component.minimumSize().
Specified by:
minimumSize in interface ComponentPeer
Returns:
the minimum size for the component

paint

public void paint(Graphics gfx)
Specified by:
paint in interface ComponentPeer

preferredSize

public Dimension preferredSize()
Returns the preferred size for the component. This is called by Component.getPreferredSize().
Specified by:
preferredSize in interface ComponentPeer
Returns:
the preferred size for the component

prepareImage

public boolean prepareImage(Image img,
                            int width,
                            int height,
                            ImageObserver o)
Prepares an image for rendering on this component. This is called by Component.prepareImage(Image,int,int,ImageObserver).
Specified by:
prepareImage in interface ComponentPeer
Parameters:
img - the image to prepare
width - the desired width of the rendered image
height - the desired height of the rendered image
Returns:
true if the image has been fully prepared, false otherwise (in which case the image observer receives updates)

print

public void print(Graphics graphics)
Specified by:
print in interface ComponentPeer

repaint

public void repaint(long tm,
                    int x,
                    int y,
                    int w,
                    int h)
Repaints the specified rectangle of this component. This is called from Component.repaint(long,int,int,int,int).
Specified by:
repaint in interface ComponentPeer
Parameters:
tm - number of milliseconds to wait with repainting
x - the X coordinate of the upper left corner of the damaged rectangle
y - the Y coordinate of the upper left corner of the damaged rectangle

reparent

public void reparent(ContainerPeer parent)
Specified by:
reparent in interface ComponentPeer
Since:
1.5

requestFocus

public void requestFocus()
Requests that this component receives the focus. This is called from Component.requestFocus().
Specified by:
requestFocus in interface ComponentPeer

requestFocus

public boolean requestFocus(Component source,
                            boolean b1,
                            boolean b2,
                            long x)
Requests that this component receives the focus. This is called from Component.requestFocus(). This method is only called for heavyweight component's peers. Lightweight components ask their nearest heavyweight component to request focus. It's up to the heavyweight peer to decide if any of it's lightweight descendants are allowed to receive keyboard input focus or not. If the focus request is finally approved, then the peer must post a FOCUS_GAINED event for the requested component.
Specified by:
requestFocus in interface ComponentPeer
Parameters:

requestFocus

public boolean requestFocus(Component source,
                            boolean b1,
                            boolean b2,
                            long x,
                            CausedFocusEvent.Cause cause)
Requests the focus on the component.
Specified by:
requestFocus in interface ComponentPeer

reshape

public void reshape(int x,
                    int y,
                    int width,
                    int height)
Notifies the peer that the bounds of this component have changed. This is called by Component.reshape(int,int,int,int).
Specified by:
reshape in interface ComponentPeer
Parameters:
x - the X coordinate of the upper left corner of the component
y - the Y coordinate of the upper left corner of the component
width - the width of the component
height - the height of the component

restack

public void restack()
Since:
1.5

setBackground

public void setBackground(Color color)
Sets the background color of the component. This is called by Component.setBackground(Color).
Specified by:
setBackground in interface ComponentPeer
Parameters:
color - the background color to set

setBounds

public void setBounds(int x,
                      int y,
                      int width,
                      int height)
Notifies the peer that the bounds of this component have changed. This is called by Component.setBounds(int,int,int,int).
Specified by:
setBounds in interface ComponentPeer
Parameters:
x - the X coordinate of the upper left corner of the component
y - the Y coordinate of the upper left corner of the component
width - the width of the component
height - the height of the component

setBounds

public void setBounds(int x,
                      int y,
                      int width,
                      int height,
                      int z)
Specified by:
setBounds in interface ComponentPeer
Since:
1.5

setCursor

public void setCursor(Cursor cursor)
Sets the cursor of the component. This is called by Component.setCursor(Cursor).
Specified by:
setCursor in interface ComponentPeer

setEnabled

public void setEnabled(boolean enabled)
Sets the enabled/disabled state of this component. This is called by Component.setEnabled(boolean).
Specified by:
setEnabled in interface ComponentPeer
Parameters:
enabled - true to enable the component, false to disable it

setEventMask

public void setEventMask(long eventMask)
Part of an older API, no longer needed.
Specified by:
setEventMask in interface ComponentPeer

setFont

public void setFont(Font font)
Sets the font of the component. This is called by Component.setFont(Font).
Specified by:
setFont in interface ComponentPeer
Parameters:
font - the font to set

setForeground

public void setForeground(Color color)
Sets the foreground color of the component. This is called by Component.setForeground(Color).
Specified by:
setForeground in interface ComponentPeer
Parameters:
color - the foreground color to set

setVisible

public void setVisible(boolean visible)
Sets the visibility state of the component. This is called by Component.setVisible(boolean).
Specified by:
setVisible in interface ComponentPeer
Parameters:
visible - true to make the component visible, false to make it invisible

show

public void show()
Makes the component visible. This is called by Component.show().
Specified by:
show in interface ComponentPeer

updateCursorImmediately

public void updateCursorImmediately()
Updates the cursor.
Specified by:
updateCursorImmediately in interface ComponentPeer

Copyright (C) 2000, 2002, 2003 Free Software Foundation This file is part of libgcj. This software is copyrighted work licensed under the terms of the Libgcj License. Please consult the file "LIBGCJ_LICENSE" for details.