java.beans
Class PropertyEditorSupport

java.lang.Object
  |
  +--java.beans.PropertyEditorSupport

public class PropertyEditorSupport

extends Object

implements PropertyEditor

This is a support class to help build property editors.

It can be used either as a base class or as a delagatee.

Constructor Summary

protected	PropertyEditorSupport() Constructor for use by derived PropertyEditor classes.
protected	PropertyEditorSupport(Object source) Constructor for use when a PropertyEditor is delegating to us.

Method Summary

void	addPropertyChangeListener(PropertyChangeListener listener) Register a listener for the PropertyChange event.
void	firePropertyChange() Report that we have been modified to any interested listeners.
String	getAsText() Gets the property value as a string suitable for presentation to a human to edit.
Component	getCustomEditor() A PropertyEditor may chose to make available a full custom Component that edits its property value.
String	getJavaInitializationString() This method is intended for use when generating Java code to set the value of the property.
String[]	getTags() If the property value must be one of a set of known tagged values, then this method should return an array of the tag values.
Object	getValue() Gets the value of the property.
boolean	isPaintable() Determines whether the class will honor the painValue method.
void	paintValue(Graphics gfx, Rectangle box) Paint a representation of the value into a given area of screen real estate.
void	removePropertyChangeListener(PropertyChangeListener listener) Remove a listener for the PropertyChange event.
void	setAsText(String text) Sets the property value by parsing a given String.
void	setValue(Object value) Set (or change) the object that is to be edited.
boolean	supportsCustomEditor() Determines whether the propertyEditor can provide a custom editor.

Methods inherited from class java.lang.Object

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

Constructor Detail

PropertyEditorSupport

protected PropertyEditorSupport()

Constructor for use by derived PropertyEditor classes.

PropertyEditorSupport

protected PropertyEditorSupport(Object source)

Constructor for use when a PropertyEditor is delegating to us.

Parameters:

source - The source to use for any events we fire.

Method Detail

setValue

public void setValue(Object value)

Set (or change) the object that is to be edited.

Specified by:

setValue in interface PropertyEditor

Parameters:

value - The new target object to be edited. Note that this object should not be modified by the PropertyEditor, rather the PropertyEditor should create a new object to hold any modified value.

getValue

public Object getValue()

Gets the value of the property.

Specified by:

getValue in interface PropertyEditor

Returns:

The value of the property.

isPaintable

public boolean isPaintable()

Determines whether the class will honor the painValue method.

Specified by:

isPaintable in interface PropertyEditor

Returns:

True if the class will honor the paintValue method.

paintValue

public void paintValue(Graphics gfx,
                       Rectangle box)

Paint a representation of the value into a given area of screen real estate. Note that the propertyEditor is responsible for doing its own clipping so that it fits into the given rectangle.

If the PropertyEditor doesn't honor paint requests (see isPaintable) this method should be a silent noop.

Specified by:

paintValue in interface PropertyEditor

Parameters:

gfx - Graphics object to paint into.

box - Rectangle within graphics object into which we should paint.

getJavaInitializationString

public String getJavaInitializationString()

This method is intended for use when generating Java code to set the value of the property. It should return a fragment of Java code that can be used to initialize a variable with the current property value.

Example results are "2", "new Color(127,127,34)", "Color.orange", etc.

Specified by:

getJavaInitializationString in interface PropertyEditor

Returns:

A fragment of Java code representing an initializer for the current value.

getAsText

public String getAsText()

Gets the property value as a string suitable for presentation to a human to edit.

Specified by:

getAsText in interface PropertyEditor

Returns:

The property value as a string suitable for presentation to a human to edit.

Returns "null" is the value can't be expressed as a string.

If a non-null value is returned, then the PropertyEditor should be prepared to parse that string back in setAsText().

setAsText

public void setAsText(String text)
               throws IllegalArgumentException

Sets the property value by parsing a given String. May raise java.lang.IllegalArgumentException if either the String is badly formatted or if this kind of property can't be expressed as text.

Specified by:

setAsText in interface PropertyEditor

Parameters:

text - The string to be parsed.

getTags

public String[] getTags()

If the property value must be one of a set of known tagged values, then this method should return an array of the tag values. This can be used to represent (for example) enum values. If a PropertyEditor supports tags, then it should support the use of setAsText with a tag value as a way of setting the value.

Specified by:

getTags in interface PropertyEditor

Returns:

The tag values for this property. May be null if this property cannot be represented as a tagged value.

getCustomEditor

public Component getCustomEditor()

A PropertyEditor may chose to make available a full custom Component that edits its property value. It is the responsibility of the PropertyEditor to hook itself up to its editor Component itself and to report property value changes by firing a PropertyChange event.

The higher-level code that calls getCustomEditor may either embed the Component in some larger property sheet, or it may put it in its own individual dialog, or ...

Specified by:

getCustomEditor in interface PropertyEditor

Returns:

A java.awt.Component that will allow a human to directly edit the current property value. May be null if this is not supported.

supportsCustomEditor

public boolean supportsCustomEditor()

Determines whether the propertyEditor can provide a custom editor.

Specified by:

supportsCustomEditor in interface PropertyEditor

Returns:

True if the propertyEditor can provide a custom editor.

addPropertyChangeListener

public void addPropertyChangeListener(PropertyChangeListener listener)

Register a listener for the PropertyChange event. The class will fire a PropertyChange value whenever the value is updated.

Specified by:

addPropertyChangeListener in interface PropertyEditor

Parameters:

listener - An object to be invoked when a PropertyChange event is fired.

removePropertyChangeListener

public void removePropertyChangeListener(PropertyChangeListener listener)

Remove a listener for the PropertyChange event.

Specified by:

removePropertyChangeListener in interface PropertyEditor

Parameters:

listener - The PropertyChange listener to be removed.

firePropertyChange

public void firePropertyChange()

Report that we have been modified to any interested listeners.

Parameters:

source - The PropertyEditor that caused the event.