Text Layout with mouse clicking and selecting action : TextLayout « 2D Graphics « Java Tutorial

1. Java Tutorial
2. 2D Graphics
3. TextLayout

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Shape;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.awt.font.FontRenderContext;
import java.awt.font.TextHitInfo;
import java.awt.font.TextLayout;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class TextLayoutWithMouseClickDrag{
  public static void main(String arg[]) {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.getContentPane().add("Center", new DisplayPanel());
    frame.pack();
    frame.setSize(new Dimension(400, 300));
    frame.setVisible(true);
  }
}

class DisplayPanel extends JPanel {
  FontRenderContext frc = new FontRenderContext(null, false, false);
  Font font = new Font("Arial", Font.PLAIN, 36);
  Rectangle2D rect;
  float rx, ry, rw, rh;

  TextHitInfo hitInfo;
  Color caretColor;
  int hit1, hit2;
  int w=400, h=200;
  TextLayout layout = new TextLayout("j a v a 2 s . c o m", font, frc);

  public DisplayPanel() {
    setSize(400, 200);
    addMouseListener(new MouseHandler());
    addMouseMotionListener(new MouseMotionHandler());

    rx = (float) (w / 2 - layout.getBounds().getWidth() / 2);
    ry = (float) 3 * h / 4;
    rw = (float) (layout.getBounds().getWidth());
    rh = (float) (layout.getBounds().getHeight());
    rect = new Rectangle2D.Float(rx, ry, rw, rh);

  }

  public void update(Graphics g) {
    g.clearRect(0, 0, getWidth(), getHeight());
    paintComponent(g);
  }

  public void paintComponent(Graphics g) {
    super.paintComponent(g);
    Graphics2D g2 = (Graphics2D) g;

    AffineTransform at = AffineTransform.getTranslateInstance(rx, ry);

    Shape hilight = layout.getLogicalHighlightShape(hit1, hit2);
    hilight = at.createTransformedShape(hilight);
    g2.setColor(Color.lightGray);
    g2.fill(hilight);

    g2.setColor(Color.black);
    layout.draw(g2, rx, ry);

    Shape[] caretShapes = layout.getCaretShapes(hit1);
    Shape caret = at.createTransformedShape(caretShapes[0]);
    g2.setColor(caretColor);
    g2.draw(caret);
  }

  public int getHitLocation(int mouseX, int mouseY) {
    hitInfo = layout.hitTestChar(mouseX, mouseY, rect);
    return hitInfo.getInsertionIndex();
  }

  class MouseHandler extends MouseAdapter {
    public void mouseClicked(MouseEvent e) {
      caretColor = getForeground();
      hit1 = getHitLocation(e.getX(), e.getY());
      hit2 = hit1;
      repaint();
    }

    public void mousePressed(MouseEvent e) {
      caretColor = getForeground();
      hit1 = getHitLocation(e.getX(), e.getY());
      hit2 = hit1;
      repaint();
    }

    public void mouseReleased(MouseEvent e) {
      hit2 = getHitLocation(e.getX(), e.getY());
      repaint();
    }
  }

  class MouseMotionHandler extends MouseMotionAdapter {
    public void mouseDragged(MouseEvent e) {
      caretColor = getBackground();
      hit2 = getHitLocation(e.getX(), e.getY());
      repaint();
    }
  }
}

16.21.TextLayout
	16.21.1.	Styled Text
	16.21.2.	Text Layout with mouse clicking and selecting action
	16.21.3.	Draw text with TextLayout
	16.21.4.	Make your own animation from a series of images
	16.21.5.	Drawing a Paragraph of Text
	16.21.6.	Getting the Shape from the Outline of Text
	16.21.7.	Drawing Text with Mixed Styles
	16.21.8.	Line Break Measurer Demo