org.jdesktop.swingx.decorator
Class AbstractHighlighter

java.lang.Object
  org.jdesktop.swingx.decorator.AbstractHighlighter

All Implemented Interfaces:

Highlighter

Direct Known Subclasses:

BorderHighlighter, ColorHighlighter, CompoundHighlighter, IconHighlighter, PainterHighlighter

public abstract class AbstractHighlighter
extends Object
implements Highlighter

Abstract Highlighter implementation which manages change notification and supports conditional highlighting. Subclasses are required to fire ChangeEvents on internal changes which might effect the highlight. The HighlightPredicate controls whether or not a highlight should be applied for the given ComponentAdapter, subclasses must guarantee to respect its decision.

Concrete custom implementations should focus on a single (or few) visual attribute to highlight. This allows easy re-use by composition. F.i. a custom FontHighlighter:

 public static class FontHighlighter extends AbstractHighlighter {
 
     private Font font;
 
     public FontHighlighter(HighlightPredicate predicate, Font font) {
         super(predicate);
         setFont(font);
     }
 
     @Override
     protected Component doHighlight(Component component,
             ComponentAdapter adapter) {
         component.setFont(font);
         return component;
     }
     
     public final void setFont(Font font) {
        if (equals(font, this.font)) return;
        this.font = font;
        fireStateChanged();
     }
     
 
 }
 
 

Client code can combine the effect with a f.i. Color decoration, and use a shared HighlightPredicate to apply both for the same condition.

 HighlightPredicate predicate = new HighlightPredicate() {
     public boolean isHighlighted(Component renderer, ComponentAdapter adapter) {
         Object value = adapter.getFilteredValueAt(adapter.row, adapter.column);
         return (value instanceof Number) && ((Number) value).intValue() < 0;
     }
 };
 table.setHighlighters(
         new ColorHighlighter(predicate, Color.RED, null),
         new FontHighlighter(predicate, myBoldFont));
 

See Also:

HighlightPredicate, ComponentProvider

Field Summary

protected WeakEventListenerList

listenerList The listeners waiting for model changes.

Constructor Summary

AbstractHighlighter()
Instantiates a Highlighter with default HighlightPredicate.

AbstractHighlighter(HighlightPredicate predicate)
Instantiates a Highlighter with the given HighlightPredicate.

Method Summary

void	addChangeListener(ChangeListener l) Adds a ChangeListener.
protected boolean	areEqual(Object oneItem, Object anotherItem) Returns true if the to objects are either both null or equal each other.
protected boolean	canHighlight(Component component, ComponentAdapter adapter) Subclasses may override to further limit the highlighting based on Highlighter state, f.i.
protected abstract Component	doHighlight(Component component, ComponentAdapter adapter) Apply the highlights.
protected void	fireStateChanged() Notifies registered ChangeListeners about state changes.
ChangeListener[]	getChangeListeners() Returns an array of all the change listeners registered on this Highlighter.
HighlightPredicate	getHighlightPredicate() Returns the HighlightPredicate used to decide whether a cell should be highlighted.
Component	highlight(Component component, ComponentAdapter adapter) Decorates the specified component for the given component adapter.
void	removeChangeListener(ChangeListener l) Removes a ChangeListenere.
void	setHighlightPredicate(HighlightPredicate predicate) Set the HighlightPredicate used to decide whether a cell should be highlighted.

Methods inherited from class java.lang.Object

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

Field Detail

listenerList

protected WeakEventListenerList listenerList

The listeners waiting for model changes.

Constructor Detail

AbstractHighlighter

public AbstractHighlighter()

Instantiates a Highlighter with default HighlightPredicate.

See Also:

setHighlightPredicate(HighlightPredicate)

AbstractHighlighter

public AbstractHighlighter(HighlightPredicate predicate)

Instantiates a Highlighter with the given HighlightPredicate.

Parameters:

predicate - the HighlightPredicate to use.

See Also:

setHighlightPredicate(HighlightPredicate)

Method Detail

setHighlightPredicate

public void setHighlightPredicate(HighlightPredicate predicate)

Set the HighlightPredicate used to decide whether a cell should be highlighted. If null, sets the predicate to HighlightPredicate.ALWAYS. The default value is HighlightPredicate.ALWAYS.

Parameters:

predicate - the HighlightPredicate to use.

getHighlightPredicate

public HighlightPredicate getHighlightPredicate()

Returns the HighlightPredicate used to decide whether a cell should be highlighted. Guaranteed to be never null.

Returns:

the HighlightPredicate to use, never null.

highlight

public Component highlight(Component component,
                           ComponentAdapter adapter)

Decorates the specified component for the given component adapter. This calls doHighlight to apply the decoration if both HighlightPredicate isHighlighted and canHighlight return true. Returns the undecorated component otherwise.

Specified by:

highlight in interface Highlighter

Parameters:

component - the cell renderer component that is to be decorated

adapter - the ComponentAdapter for this decorate operation

Returns:

the decorated cell rendering component

See Also:

canHighlight(Component, ComponentAdapter), doHighlight(Component, ComponentAdapter), getHighlightPredicate()

canHighlight

protected boolean canHighlight(Component component,
                               ComponentAdapter adapter)

Subclasses may override to further limit the highlighting based on Highlighter state, f.i. a PainterHighlighter can only be applied to PainterAware components.

This implementation returns true always.

Parameters:

component -

adapter -

Returns:

a boolean indication if the adapter can be highlighted based general state. This implementation returns true always.

doHighlight

protected abstract Component doHighlight(Component component,
                                         ComponentAdapter adapter)

Apply the highlights.

Parameters:

component - the cell renderer component that is to be decorated

adapter - the ComponentAdapter for this decorate operation

See Also:

highlight(Component, ComponentAdapter)

areEqual

protected boolean areEqual(Object oneItem,
                           Object anotherItem)

Returns true if the to objects are either both null or equal each other.

Parameters:

oneItem - one item

anotherItem - another item

Returns:

true if both are null or equal other, false otherwise.

addChangeListener

public final void addChangeListener(ChangeListener l)

Adds a ChangeListener. ChangeListeners are notified after changes of any attribute.

Specified by:

addChangeListener in interface Highlighter

Parameters:

l - the ChangeListener to add

See Also:

removeChangeListener(javax.swing.event.ChangeListener)

removeChangeListener

public final void removeChangeListener(ChangeListener l)

Removes a ChangeListenere.

Specified by:

removeChangeListener in interface Highlighter

Parameters:

l - the ChangeListener to remove

See Also:

addChangeListener(javax.swing.event.ChangeListener)

getChangeListeners

public final ChangeListener[] getChangeListeners()

Returns an array of all the change listeners registered on this Highlighter.

Specified by:

getChangeListeners in interface Highlighter

Returns:

all of this model's ChangeListeners or an empty array if no change listeners are currently registered

Since:

1.4

See Also:

addChangeListener(javax.swing.event.ChangeListener), removeChangeListener(javax.swing.event.ChangeListener)

fireStateChanged

protected final void fireStateChanged()

Notifies registered ChangeListeners about state changes.

Note: subclasses should be polite and implement any property setters to fire only if the property is really changed.