Packages This Package Prev Next Index
§1.41 Class Toolkit
public abstract class java.awt.Toolkit
extends java.lang.Object (I-§1.12)
{
// Constructors
public Toolkit(); §1.41.1
// Methods
public abstract int §1.41.2
checkImage(Image image, int width, int height,
ImageObserver observer);
protected abstract ButtonPeer §1.41.3
createButton(Button target);
protected abstract CanvasPeer §1.41.4
createCanvas(Canvas target);
protected abstract CheckboxPeer §1.41.5
createCheckbox(Checkbox target);
protected abstract CheckboxMenuItemPeer §1.41.6
createCheckboxMenuItem(CheckboxMenuItem target);
protected abstract ChoicePeer §1.41.7
createChoice(Choice target);
protected abstract DialogPeer §1.41.8
createDialog(Dialog target);
protected abstract FileDialogPeer §1.41.9
createFileDialog(FileDialog target);
protected abstract FramePeer createFrame(Frame target); §1.41.10
public abstract Image §1.41.11
createImage(ImageProducer producer);
protected abstract LabelPeer createLabel(Label target); §1.41.12
protected abstract ListPeer createList(List target); §1.41.13
protected abstract MenuPeer createMenu(Menu target); §1.41.14
protected abstract MenuBarPeer §1.41.15
createMenuBar(MenuBar target);
protected abstract MenuItemPeer §1.41.16
createMenuItem(MenuItem target);
protected abstract PanelPeer createPanel(Panel target); §1.41.17
protected abstract ScrollbarPeer §1.41.18
createScrollbar(Scrollbar target);
protected abstract TextAreaPeer §1.41.19
createTextArea(TextArea target);
protected abstract TextFieldPeer §1.41.20
createTextField(TextField target);
protected abstract WindowPeer §1.41.21
createWindow(Window target);
public abstract ColorModel getColorModel(); §1.41.22
public static Toolkit getDefaultToolkit(); §1.41.23
public abstract String[] getFontList(); §1.41.24
public abstract FontMetrics §1.41.25
getFontMetrics(Font font);
public abstract Image getImage(String filename); §1.41.26
public abstract Image getImage(URL url); §1.41.27
public abstract int getScreenResolution(); §1.41.28
public abstract Dimension getScreenSize(); §1.41.29
public abstract boolean §1.41.30
prepareImage(Image image, int width, int height,
ImageObserver observer);
public abstract void sync(); §1.41.31
}
This class is the abstract superclass of all actual implementations of the Abstract Window
Toolkit. Subclasses of the class are used to bind the various components to particular
native toolkit implementations.
Most applications should not call any of the methods is this class directly. These methods
are called by the addNotify methods of the various components in the Abstract Window
Toolkit.
Toolkit
public Toolkit()
- The default constructor for a toolkit.
checkImage
public abstract int
checkImage(Image image, int width, int height,
ImageObserver observer)
- If the width and height arguments are both -1, this method returns the status of the construction of a screen representaion of the specified image in
this toolkit. Otherwise, this method returns the status of the construction of
a scaled representation of the specified image at the specified width and
height.
- This method does not cause the image to begin loading. An application
must use the prepareImage (II-§1.41.30) method to force the loading of an
image.
- This toolkit method is used by the checkImage methods (II-§1.10.4,
§1.10.5) of Component.
- Information on the flags returned by this method can be found in II-§2.11.
- Parameters:
image
- the image whose status is being checked
width
- the width of the scaled version to check the status of
height
- the height of the scaled version to check the status of
observer
- the ImageObserver object to be notified as the image is being
prepared
- Returns:
- the bitwise inclusive OR of the ImageObserver (II-§2.11) flags indicating what information about the image is available.
createButton
protected abstract ButtonPeer createButton(Button target)
- Parameters:
target
- the button to be implemented
- Returns:
- this toolkit's implementation of a Button (II-§1.2).
createCanvas
protected abstract CanvasPeer createCanvas(Canvas target)
- Parameters:
target
- the canvas to be implemented
- Returns:
- this toolkit's implementation of a Canvas (II-§1.3).
createCheckbox
protected abstract CheckboxPeer
createCheckbox(Checkbox target)
- Parameters:
target
- the check box to be implemented
- Returns:
- this toolkit's implementation of a Checkbox (II-§1.5).
createCheckboxMenuItem
protected abstract CheckboxMenuItemPeer
createCheckboxMenuItem(CheckboxMenuItem target)
- Parameters:
target
- the check box menu item to be implemented
- Returns:
- this toolkit's implementation of a CheckboxMenuItem (II-§1.7).
createChoice
protected abstract ChoicePeer createChoice(Choice target)
- Parameters:
target
- the choice list to be implemented
- Returns:
- this toolkit's implementation of a Choice (II-§1.8).
createDialog
protected abstract DialogPeer createDialog(Dialog target)
- Parameters:
target
- the dialog window to be implemented
- Returns:
- this toolkit's implementation of a Dialog (II-§1.12).
createFileDialog
protected abstract FileDialogPeer
createFileDialog(FileDialog target)
- Parameters:
target
- the filie dialog window to be implemented
- Returns:
- this toolkit's implementation of a FileDialog (II-§1.15).
createFrame
protected abstract FramePeer createFrame(Frame target)
- Parameters:
target
- the frame to be implemented
- Returns:
- this toolkit's implementation of a Frame (II-§1.19).
createImage
public abstract Image createImage(ImageProducer producer)
- Parameters:
target
- the image to be implemented
- Returns:
- this toolkit's implementation of an Image (II-§1.24).
createLabel
protected abstract LabelPeer createLabel(Label target)
- Parameters:
target
- the label to be implemented
- Returns:
- this toolkit's implementation of a Label (II-§1.26).
createList
protected abstract ListPeer createList(List target)
- Parameters:
target
- the scrolling list to be implemented
- Returns:
- this toolkit's implementation of a List (II-§1.27).
createMenu
protected abstract MenuPeer createMenu(Menu target)
- Parameters:
target
- the menu to be implemented
- Returns:
- this toolkit's implementation of a Menu (II-§1.29).
createMenuBar
protected abstract MenuBarPeer
createMenuBar(MenuBar target)
- Parameters:
target
- the menu bar to be implemented
- Returns:
- this toolkit's implementation of a MenuBar (II-§1.30).
createMenuItem
protected abstract MenuItemPeer
createMenuItem(MenuItem target)
- Parameters:
target
- the menu item to be implemented
- Returns:
- this toolkit's implementation of a MenuItem (II-§1.32).
createPanel
protected abstract PanelPeer createPanel(Panel target)
- Parameters:
target
- the panel to be implemented
- Returns:
- this toolkit's of a Panel (II-§1.33).
createScrollbar
protected abstract ScrollbarPeer
createScrollbar(Scrollbar target)
- Parameters:
target
- the scroll bar to be implemented
- Returns:
- this toolkit's implementation of a ScrollBar (II-§1.37).
createTextArea
protected abstract TextAreaPeer
createTextArea(TextArea target)
- Parameters:
target
- the text area to be implemented
- Returns:
- this toolkit's implementation of a TextArea (II-§1.38).
createTextField
protected abstract TextFieldPeer
createTextField(TextField target)
- Parameters:
target
- the text field to be implemented
- Returns:
- this toolkit's implementation of a TextField (II-§1.40).
createWindow
protected abstract WindowPeer createWindow(Window target)
- Parameters:
target
- the window to be implemented
- Returns:
- this toolkit's implementation of a Window (II-§1.42).
getColorModel
public abstract ColorModel getColorModel()
- Determine's the color model of this toolkit's screen.
- The ColorModel (II-§2.1) is an abstract class that encapsulates how to translate between pixel values of an image and its red, green, blue, and alpha
components.
- This toolkit method is used by the getColorModel method (II-§1.10.13) of
Component.
- Returns:
- the color model of the tookit's screen.
getDefaultToolkit
public static Toolkit getDefaultToolkit()
- Gets the default toolkit.
- If there is a system property named "awt.toolkit", that property is treated as
the name of a class that is a subclass of Toolkit.
- If the system property does not exist, then the default toolkit used is the
class named "sun.awt.motif.MToolkit", which is a motif implementation of the
Abstract Window Toolkit.
- Returns:
- the default toolkit.
- Throws
- AWTError (II-§1.46)
- If a toolkit could not be found or could not be instantiated.
getFontList
public abstract String[] getFontList()
- Returns:
- the names of the available fonts in this toolkit.
getFontMetrics
public abstract FontMetrics getFontMetrics(Font font)
- Parameters:
font
- a font
- Returns:
- the screen metrics of the font argument in this toolkit.
getImage
public abstract Image getImage(String filename)
- Parameters:
filename
- a file containing pixel data in a recognized file format
- Returns:
- an image which gets its pixel data from the specified file
getImage
public abstract Image getImage(URL url)
- Parameters:
url
- a URL which specifies an image.
- Returns:
- an image which gets its pixel data from the specified URL.
getScreenResolution
public abstract int getScreenResolution()
- Returns:
- this toolkit's screen resolution in dots-per-inch.
getScreenSize
public abstract Dimension getScreenSize()
- Returns:
- the size of this toolkit's screen in pixels.
prepareImage
public abstract boolean
prepareImage(Image image, int width, int height,
ImageObserver observer)
- Prepares an image for rendering. If the width and height arguments are
both -1, this method prepares the image for rendering on the default
screen; otherwise, this method prepares an image for rendering on the
default screen at the specified width and height.
- The image data is downloaded asynchronously in another thread and an
appropriately scaled screen representation of the image is generated.
- This toolkit method is used by the prepareImage methods (II-§1.10.54,
§1.10.55) of Component.
- Information on the flags returned by this method can be found in II-§2.11.
- Parameters:
image
- the image to prepare a screen representation for
width
- the width of the desired screen representation
height
- the height of the desired screen representation
observer
- the ImageObserver object to be notified as the image is being
prepared
- Returns:
- true if the image has already been fully prepared; false otherwise
sync
public abstract void sync()
- Synchronizes this toolkit's graphics state. Some window systems may do
buffering of graphics events. This method ensures that the display is up to
date.
Packages This Package Prev Next Index
Java API Document (HTML generated by dkramer on April 22, 1996)
Copyright © 1996 Sun Microsystems, Inc.
All rights reserved
Please send any comments or corrections to doug.kramer@sun.com