org.fife.ui.rsyntaxtextarea.SquiggleUnderlineHighlightPainter Maven / Gradle / Ivy
/*
* 09/13/2005
*
* SquiggleUnderlineHighlightPainter.java - Highlighter that draws a squiggle
* underline under "highlighted" text, similar to error markers in Microsoft
* Visual Studio or Eclipse.
*
* This library is distributed under a modified BSD license. See the included
* RSyntaxTextArea.License.txt file for details.
*/
package org.fife.ui.rsyntaxtextarea;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.Shape;
import javax.swing.text.BadLocationException;
import javax.swing.text.JTextComponent;
import javax.swing.text.Position;
import javax.swing.text.View;
import org.fife.ui.rtextarea.ChangeableHighlightPainter;
/**
* Highlight painter that paints a squiggly underline underneath text, similar
* to what popular IDE's such as Visual Studio and Eclipse do to indicate
* errors, warnings, etc.
*
* This class must be used as a LayerPainter.
*
* @author Robert Futrell
* @version 1.0
*/
public class SquiggleUnderlineHighlightPainter
extends ChangeableHighlightPainter {
private static final int AMT = 2;
/**
* Constructor.
*
* @param color The color of the squiggle. This cannot be
* null.
*/
public SquiggleUnderlineHighlightPainter(Color color) {
super(color);
setPaint(color);
}
/**
* Paints a portion of a highlight.
*
* @param g the graphics context
* @param offs0 the starting model offset >= 0
* @param offs1 the ending model offset >= offs1
* @param bounds the bounding box of the view, which is not
* necessarily the region to paint.
* @param c the editor
* @param view View painting for
* @return region drawing occurred in
*/
@Override
public Shape paintLayer(Graphics g, int offs0, int offs1,
Shape bounds, JTextComponent c, View view) {
g.setColor((Color)getPaint());
if (offs0 == view.getStartOffset() && offs1 == view.getEndOffset()) {
// Contained in view, can just use bounds.
Rectangle alloc;
if (bounds instanceof Rectangle)
alloc = (Rectangle)bounds;
else
alloc = bounds.getBounds();
paintSquiggle(g, alloc);
return alloc;
}
// Otherwise, should only render part of View.
try {
// --- determine locations ---
Shape shape = view.modelToView(offs0, Position.Bias.Forward,
offs1,Position.Bias.Backward,
bounds);
Rectangle r = (shape instanceof Rectangle) ?
(Rectangle)shape : shape.getBounds();
paintSquiggle(g, r);
return r;
} catch (BadLocationException e) {
e.printStackTrace(); // can't render
}
// Only if exception
return null;
}
/**
* Paints a squiggle underneath text in the specified rectangle.
*
* @param g The graphics context with which to paint.
* @param r The rectangle containing the text.
*/
protected void paintSquiggle(Graphics g, Rectangle r) {
int x = r.x;
int y = r.y + r.height - AMT;
int delta = -AMT;
while (x