org.fife.ui.rtextarea.AbstractGutterComponent Maven / Gradle / Ivy
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/*
* 02/17/2009
*
* AbstractGutterComponent.java - A component that can be displayed in a Gutter.
*
* This library is distributed under a modified BSD license. See the included
* LICENSE file for details.
*/
package org.fife.ui.rtextarea;
import java.awt.Container;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.*;
import javax.swing.event.DocumentEvent;
import javax.swing.text.View;
/**
* A component that can be displayed in a {@link Gutter}.
*
* @author Robert Futrell
* @version 1.0
*/
abstract class AbstractGutterComponent extends JPanel {
/**
* The text area whose lines we are marking with icons.
*/
protected RTextArea textArea;
/**
* The number of lines in the text area.
*/
protected int currentLineCount;
private static Listener listener;
/**
* Constructor.
*
* @param textArea The text area.
*/
AbstractGutterComponent(RTextArea textArea) {
init(); // Called before setTextArea().
setTextArea(textArea);
}
@Override
public void addNotify() {
super.addNotify();
getListener().install(this);
}
/**
* Returns the bounds of a child view as a rectangle, since
* Views tend to use Shape.
*
* @param parent The parent view of the child whose bounds we're getting.
* @param line The index of the child view.
* @param editorRect Returned from the text area's
* getVisibleEditorRect method.
* @return The child view's bounds.
*/
protected static Rectangle getChildViewBounds(View parent, int line,
Rectangle editorRect) {
Shape alloc = parent.getChildAllocation(line, editorRect);
if (alloc==null) {
// WrappedSyntaxView can have this when made so small it's
// no longer visible
return new Rectangle();
}
return alloc instanceof Rectangle ? (Rectangle)alloc :
alloc.getBounds();
}
/**
* Returns the parent Gutter component.
*
* @return The parent Gutter.
*/
protected Gutter getGutter() {
Container parent = getParent();
return (parent instanceof Gutter) ? (Gutter)parent : null;
}
/**
* Returns the singleton instance of the listener for all gutter components.
*
* @return The singleton instance.
*/
private static Listener getListener() {
if (listener == null) {
listener = new Listener();
}
return listener;
}
/**
* Called when text is inserted to or removed from the text area.
* Implementations can take this opportunity to repaint, revalidate, etc.
*
* @param e The document event.
* @see #handleDocumentUpdated(RDocument, RDocument)
*/
abstract void handleDocumentEvent(DocumentEvent e);
/**
* Called when the document is updated. This happens when an application
* calls {@code textArea.read(reader)}, for example.
*
* The default implementation does nothing. Subclasses can override.
*
* @param oldDoc The old document, which may be {@code null}.
* @param newDoc The new document, which may be {@code null}.
* @see #handleDocumentEvent(DocumentEvent)
*/
void handleDocumentUpdated(RDocument oldDoc, RDocument newDoc) {
// Do nothing
}
/**
* Called by the constructor before the text area is set. This is a hook
* to allow subclasses to do any needed initialization. The default
* implementation does nothing.
*/
protected void init() {
}
/**
* Called when the line heights of the text area change. This is usually
* the result of one or more of the fonts in the editor changing.
*/
abstract void lineHeightsChanged();
@Override
public void removeNotify() {
getListener().uninstall(this);
super.removeNotify();
}
/**
* Sets the text area being displayed. Subclasses can override, but
* should call the super implementation.
*
* @param textArea The text area.
*/
public void setTextArea(RTextArea textArea) {
this.textArea = textArea;
int lineCount = textArea==null ? 0 : textArea.getLineCount();
if (currentLineCount!=lineCount) {
currentLineCount = lineCount;
repaint();
}
}
static class Listener extends MouseAdapter {
private boolean newArmed;
void install(AbstractGutterComponent component) {
component.addMouseListener(this);
component.addMouseMotionListener(this);
}
public void mouseExited(MouseEvent e) {
setArmed((AbstractGutterComponent)e.getComponent(), false);
}
public void mouseMoved(MouseEvent e) {
setArmed((AbstractGutterComponent)e.getComponent(), true);
}
private void setArmed(AbstractGutterComponent component, boolean armed) {
newArmed = armed;
SwingUtilities.invokeLater(() -> {
if (component.getGutter() != null && newArmed != component.getGutter().isArmed()) {
component.getGutter().setArmed(newArmed);
}
});
}
void uninstall(AbstractGutterComponent component) {
component.removeMouseListener(this);
component.removeMouseMotionListener(this);
}
}
}