org.fife.rsta.ui.AssistanceIconPanel Maven / Gradle / Ivy
/*
* 06/13/2009
*
* AssistanceIconPanel.java - A panel that sits alongside a text component,
* that can display assistance icons for that component.
* This library is distributed under a modified BSD license. See the included
* RSTAUI.License.txt file for details.
*/
package org.fife.rsta.ui;
import java.awt.Component;
import java.awt.Image;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.ImageIcon;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.text.JTextComponent;
import org.fife.rsta.ui.search.AbstractSearchDialog;
/**
* A panel meant to be displayed alongside a text component, that can display
* assistance icons for that text component.
*
* @author Robert Futrell
* @version 1.0
*/
public class AssistanceIconPanel extends DecorativeIconPanel
implements PropertyChangeListener {
/**
* The tool tip text for the light bulb icon. It is assumed that access
* to this field is single-threaded (on the EDT).
*/
private static String ASSISTANCE_AVAILABLE;
/**
* Constructor.
*
* @param comp The component to listen to. This can be null
* to create a "filler" icon panel for alignment purposes.
*/
public AssistanceIconPanel(JComponent comp) {
// null can be passed to make a "filler" icon panel for alignment
// purposes.
if (comp!=null) {
ComponentListener listener = new ComponentListener();
if (comp instanceof JComboBox) {
JComboBox combo = (JComboBox)comp;
Component c = combo.getEditor().getEditorComponent();
if (c instanceof JTextComponent) { // Always true
JTextComponent tc = (JTextComponent)c;
tc.addFocusListener(listener);
}
}
else { // Usually a JTextComponent
comp.addFocusListener(listener);
}
comp.addPropertyChangeListener(
ContentAssistable.ASSISTANCE_IMAGE, this);
}
}
/**
* Returns the "Content Assist Available" tool tip text for the light bulb
* icon. It is assumed that this method is only called on the EDT.
*
* @return The text.
*/
static String getAssistanceAvailableText() {
if (ASSISTANCE_AVAILABLE==null) {
ASSISTANCE_AVAILABLE = AbstractSearchDialog.getString("ContentAssistAvailable");
}
return ASSISTANCE_AVAILABLE;
}
/**
* Called when the property
* {@link ContentAssistable#ASSISTANCE_IMAGE} is fired by the component
* we are listening to.
*
* @param e The change event.
*/
public void propertyChange(PropertyChangeEvent e) {
Image img = (Image)e.getNewValue();
setAssistanceEnabled(img);
}
/**
* A hook for applications to initialize this panel, if the component
* we're listening to already has content assist enabled.
*
* @param img The image to display, or null if content assist
* is not currently available.
*/
public void setAssistanceEnabled(Image img) {
if (img==null) {
setIcon(EMPTY_ICON);
setToolTipText(null);
}
else {
setIcon(new ImageIcon(img));
setToolTipText(getAssistanceAvailableText());
}
}
/**
* Listens for events in the text component we're annotating.
*/
private class ComponentListener implements FocusListener {
/**
* Called when the combo box or text component gains focus.
*
* @param e The focus event.
*/
public void focusGained(FocusEvent e) {
setShowIcon(true);
}
/**
* Called when the combo box or text component loses focus.
*
* @param e The focus event.
*/
public void focusLost(FocusEvent e) {
setShowIcon(false);
}
}
}