java.awt
Class FileDialog

java.lang.Object
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  +--java.awt.Component
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        +--java.awt.Container
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              +--java.awt.Window
                    |
                    +--java.awt.Dialog
                          |
                          +--java.awt.FileDialog

public class FileDialog

extends Dialog

The FileDialog class displays a dialog window from which the user can select a file.

Since it is a modal dialog, when the application calls its show method to display the dialog, it blocks the rest of the application until the user has chosen a file.

Since:

JDK1.0

See Also:

Window.show(), Serialized Form

Field Summary

static int	LOAD This constant value indicates that the purpose of the file dialog window is to locate a file from which to read.
static int	SAVE This constant value indicates that the purpose of the file dialog window is to locate a file to which to write.

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Constructor Summary

FileDialog(Frame parent)
Creates a file dialog for loading a file.

FileDialog(Frame parent, String title)
Creates a file dialog window with the specified title for loading a file.

FileDialog(Frame parent, String title, int mode)
Creates a file dialog window with the specified title for loading or saving a file.

Method Summary

void	addNotify() Creates the file dialog's peer.
String	getDirectory() Gets the directory of this file dialog.
String	getFile() Gets the selected file of this file dialog.
FilenameFilter	getFilenameFilter() Determines this file dialog's filename filter.
int	getMode() Indicates whether this file dialog box is for loading from a file or for saving to a file.
protected String	paramString() Returns the parameter string representing the state of this file dialog window.
void	setDirectory(String dir) Sets the directory of this file dialog window to be the specified directory.
void	setFile(String file) Sets the selected file for this file dialog window to be the specified file.
void	setFilenameFilter(FilenameFilter filter) Sets the filename filter for this file dialog window to the specified filter.
void	setMode(int mode) Sets the mode of the file dialog.

Methods inherited from class java.awt.Dialog

getTitle, isModal, isResizable, setModal, setResizable, setTitle, show

Methods inherited from class java.awt.Window

addWindowListener, applyResourceBundle, applyResourceBundle, dispose, finalize, getFocusOwner, getInputContext, getLocale, getOwnedWindows, getOwner, getToolkit, getWarningString, isShowing, pack, postEvent, processEvent, processWindowEvent, removeWindowListener, toBack, toFront

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getInsets, getLayout, getMaximumSize, getMinimumSize, getPreferredSize, insets, invalidate, isAncestorOf, layout, list, list, locate, minimumSize, paint, paintComponents, preferredSize, print, printComponents, processContainerEvent, remove, remove, removeAll, removeContainerListener, removeNotify, setFont, setLayout, update, validate, validateTree

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, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getInputMethodRequests, getLocation, getLocation, getLocationOnScreen, getName, getParent, getPeer, getSize, getSize, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setForeground, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, size, toString, transferFocus

Methods inherited from class java.lang.Object

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

Field Detail

LOAD

public static final int LOAD

This constant value indicates that the purpose of the file dialog window is to locate a file from which to read.

SAVE

public static final int SAVE

This constant value indicates that the purpose of the file dialog window is to locate a file to which to write.

Constructor Detail

FileDialog

public FileDialog(Frame parent)

Creates a file dialog for loading a file. The title of the file dialog is initially empty.

Parameters:

parent - the owner of the dialog

Since:

JDK1.1

FileDialog

public FileDialog(Frame parent,
                  String title)

Creates a file dialog window with the specified title for loading a file. The files shown are those in the current directory.

Parameters:

parent - the owner of the dialog.

title - the title of the dialog.

FileDialog

public FileDialog(Frame parent,
                  String title,
                  int mode)

Creates a file dialog window with the specified title for loading or saving a file.

If the value of mode is LOAD, then the file dialog is finding a file to read. If the value of mode is SAVE, the file dialog is finding a place to write a file.

Parameters:

parent - the owner of the dialog.

title - the title of the dialog.

mode - the mode of the dialog.

See Also:

LOAD, SAVE

Method Detail

addNotify

public void addNotify()

Creates the file dialog's peer. The peer allows us to change the look of the file dialog without changing its functionality.

Overrides:

addNotify in class Dialog

getMode

public int getMode()

Indicates whether this file dialog box is for loading from a file or for saving to a file.

Returns:

the mode of this file dialog window, either FileDialog.LOAD or FileDialog.SAVE.

See Also:

LOAD, SAVE, setMode(int)

setMode

public void setMode(int mode)

Sets the mode of the file dialog.

Parameters:

mode - the mode for this file dialog, either FileDialog.LOAD or FileDialog.SAVE.

Throws:

IllegalArgumentException - if an illegal file dialog mode is used.

Since:

JDK1.1

See Also:

LOAD, SAVE, getMode()

getDirectory

public String getDirectory()

Gets the directory of this file dialog.

Returns:

the (potentially null or invalid) directory of this FileDialog.

See Also:

setDirectory(java.lang.String)

setDirectory

public void setDirectory(String dir)

Sets the directory of this file dialog window to be the specified directory. Specifying a null or an invalid directory implies an implementation-defined default. This default will not be realized, however, until the user has selected a file. Until this point, getDirectory() will return the value passed into this method.

Specifying "" as the directory is exactly equivalent to specifying null as the directory.

Parameters:

dir - the specific directory.

See Also:

getDirectory()

getFile

public String getFile()

Gets the selected file of this file dialog.

Returns:

the currently selected file of this file dialog window, or null if none is selected.

See Also:

setFile(java.lang.String)

setFile

public void setFile(String file)

Sets the selected file for this file dialog window to be the specified file. This file becomes the default file if it is set before the file dialog window is first shown.

Specifying "" as the file is exactly equivalent to specifying null as the file.

Parameters:

file - the file being set.

See Also:

getFile()

getFilenameFilter

public FilenameFilter getFilenameFilter()

Determines this file dialog's filename filter. A filename filter allows the user to specify which files appear in the file dialog window.

Returns:

this file dialog's filename filter.

See Also:

FilenameFilter, setFilenameFilter(java.io.FilenameFilter)

setFilenameFilter

public void setFilenameFilter(FilenameFilter filter)

Sets the filename filter for this file dialog window to the specified filter.

Parameters:

filter - the specified filter.

See Also:

FilenameFilter, getFilenameFilter()

paramString

protected String paramString()

Returns the parameter string representing the state of this file dialog window. This string is useful for debugging.

Returns:

the parameter string of this file dialog window.

Overrides:

paramString in class Dialog