Change drawing area of selected highlight in JEditorPane

• download example.jar
• download src.zip
• repository

Code

class ParagraphMarkHighlightPainter extends DefaultHighlightPainter {
  protected ParagraphMarkHighlightPainter(Color color) {
    super(color);
  }

  @Override public Shape paintLayer(
      Graphics g, int offs0, int offs1,
      Shape bounds, JTextComponent c, View view) {
    Shape s = super.paintLayer(g, offs0, offs1, bounds, c, view);
    Rectangle r = s.getBounds();
    if (r.width - 1 <= 0) {
      g.fillRect(r.x + r.width, r.y, r.width + r.height / 2, r.height);
    }
    return s;
  }
}

class WholeLineHighlightPainter extends DefaultHighlightPainter {
  protected WholeLineHighlightPainter(Color color) {
    super(color);
  }

  @Override public Shape paintLayer(
      Graphics g, int offs0, int offs1,
      Shape bounds, JTextComponent c, View view) {
    Rectangle rect = bounds.getBounds();
    rect.width = c.getSize().width;
    return super.paintLayer(g, offs0, offs1, rect, c, view);
  }
}

References

• Change drawing area of selected highlight in JEditorPane(Japanese)

Create a minimap of JEditorPane with ImageIcon and overlay it on JScrollPane using LayoutManager

• download example.jar
• download src.zip
• repository

Code

private final JEditorPane editor = new JEditorPane();
private final JScrollPane scroll = new JScrollPane(editor);
private final JLabel label = new JLabel() {
  private transient MouseInputListener handler;
  @Override public void updateUI() {
    removeMouseListener(handler);
    removeMouseMotionListener(handler);
    super.updateUI();
    handler = new MiniMapHandler();
    addMouseListener(handler);
    addMouseMotionListener(handler);
  }

  @Override public void paintComponent(Graphics g) {
    super.paintComponent(g);
    Container c = SwingUtilities.getAncestorOfClass(JViewport.class, editor);
    if (!(c instanceof JViewport) || editor == null) {
      return;
    }
    JViewport vport = (JViewport) c;
    Rectangle vrect = vport.getBounds(); // scroll.getViewportBorderBounds();
    Rectangle erect = editor.getBounds();
    Rectangle crect = SwingUtilities.calculateInnerArea(this, new Rectangle());

    Graphics2D g2 = (Graphics2D) g.create();
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_ON);
    double sy = crect.getHeight() / erect.getHeight();
    AffineTransform at = AffineTransform.getScaleInstance(1d, sy);

    // paint Thumb
    Rectangle thumbRect = new Rectangle(vrect);
    thumbRect.y = vport.getViewPosition().y;
    Rectangle r = at.createTransformedShape(thumbRect).getBounds();
    int y = crect.y + r.y;
    g2.setColor(THUMB_COLOR);
    g2.fillRect(0, y, crect.width, r.height);
    g2.setColor(THUMB_COLOR.darker());
    g2.drawRect(0, y, crect.width - 1, r.height - 1);
    g2.dispose();
  }
};

private class MiniMapHandler extends MouseInputAdapter {
  @Override public void mousePressed(MouseEvent e) {
    processMiniMapMouseEvent(e);
  }

  @Override public void mouseDragged(MouseEvent e) {
    processMiniMapMouseEvent(e);
  }

  protected final void processMiniMapMouseEvent(MouseEvent e) {
    Point pt = e.getPoint();
    Component c = (Component) e.getComponent();
    BoundedRangeModel m = scroll.getVerticalScrollBar().getModel();
    int brm = m.getMaximum() - m.getMinimum();
    int iv = (int) (.5 - m.getExtent() * .5 + pt.y * brm / (double) c.getHeight());
    m.setValue(iv);
  }
}
// ...
scroll.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
scroll.getVerticalScrollBar().getModel().addChangeListener(e -> label.repaint());

JPanel pp = new JPanel(new BorderLayout(0, 0));
pp.add(label, BorderLayout.NORTH);
JScrollPane minimap = new JScrollPane(pp);
minimap.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_NEVER);
minimap.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);

Box box = Box.createHorizontalBox();
box.setBorder(BorderFactory.createEmptyBorder(2, 2, 2, 2));
box.add(Box.createHorizontalGlue());
box.add(button);

JPanel p = new JPanel() {
  @Override public boolean isOptimizedDrawingEnabled() {
    return false;
  }
};
p.setLayout(new BorderLayout(0, 0) {
  @Override public void layoutContainer(Container parent) {
    synchronized (parent.getTreeLock()) {
      Insets insets = parent.getInsets();
      int width = parent.getWidth();
      int height = parent.getHeight();
      int top = insets.top;
      int bottom = height - insets.bottom;
      int left = insets.left;
      int right = width - insets.right;
      Component ec = getLayoutComponent(parent, BorderLayout.EAST);
      if (Objects.nonNull(ec)) {
        Dimension d = ec.getPreferredSize();
        JScrollBar vsb = scroll.getVerticalScrollBar();
        int vsw = vsb.isVisible() ? vsb.getSize().width : 0;
        ec.setBounds(right - d.width - vsw, top, d.width, bottom - top);
      }
      Component cc = getLayoutComponent(parent, BorderLayout.CENTER);
      if (Objects.nonNull(cc)) {
        cc.setBounds(left, top, right - left, bottom - top);
      }
    }
  }
});
p.add(minimap, BorderLayout.EAST);
p.add(scroll);

References

• Create a minimap of JEditorPane with ImageIcon and overlay it on JScrollPane using LayoutManager(Japanese)

Enable focus move by tab key in cell editor of JTable

• download example.jar
• download src.zip
• repository

Code

JTable table = makeTable();
ActionMap am = table.getActionMap();
Action sncc = am.get("selectNextColumnCell");
Action action = new AbstractAction() {
  @Override public void actionPerformed(ActionEvent e) {
    if (!table.isEditing() || !isEditorFocusCycle(table.getEditorComponent())) {
      // System.out.println("Exit editor");
      sncc.actionPerformed(e);
    }
  }
};
am.put("selectNextColumnCell2", action);

InputMap im = table.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
im.put(KeyStroke.getKeyStroke(KeyEvent.VK_TAB, 0), "selectNextColumnCell2");
// ...
protected boolean isEditorFocusCycle(Component editor) {
  Component child = CheckBoxesEditor.getEditorFocusCycleAfter(editor);
  if (child != null) {
    child.requestFocus();
    return true;
  }
  return false;
}
// ...
public static Component getEditorFocusCycleAfter(Component editor) {
  Component fo = KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner();
  if (fo == null || !(editor instanceof Container)) {
    return null;
  }
  Container root = (Container) editor;
  if (!root.isFocusCycleRoot()) {
    root = root.getFocusCycleRootAncestor();
  }
  if (root == null) {
    return null;
  }
  // System.out.println("FocusCycleRoot: " + root.getClass().getName());
  FocusTraversalPolicy ftp = root.getFocusTraversalPolicy();
  Component child = ftp.getComponentAfter(root, fo);
  if (child != null && SwingUtilities.isDescendingFrom(child, editor)) {
    // System.out.println("requestFocus: " + child.getClass().getName());
    // child.requestFocus();
    return child;
  }
  return null;
}

References

• Enable focus move by tab key in cell editor of JTable(Japanese)

Make JToolTip translucent, and change its shape and display position

• download example.jar
• download src.zip
• repository

Code

class BalloonToolTip extends JToolTip {
  private static final int TRI_HEIGHT = 4;
  private HierarchyListener listener;

  @Override public void updateUI() {
    removeHierarchyListener(listener);
    super.updateUI();
    listener = e -> {
      Component c = e.getComponent();
      if ((e.getChangeFlags() & HierarchyEvent.SHOWING_CHANGED) != 0
          && c.isShowing()) {
        Optional.ofNullable(SwingUtilities.getRoot(c))
           .filter(JWindow.class::isInstance).map(JWindow.class::cast)
           .ifPresent(w -> w.setBackground(new Color(0x0, true)));
      }
    };
    addHierarchyListener(listener);
    setOpaque(false);
    setForeground(Color.WHITE);
    setBackground(new Color(0xC8_00_00_00, true));
    setBorder(BorderFactory.createEmptyBorder(5, 5, 5 + TRI_HEIGHT, 5));
  }

  @Override public Dimension getPreferredSize() {
    Dimension d = super.getPreferredSize();
    d.height = 32;
    return d;
  }

  @Override protected void paintComponent(Graphics g) {
    Shape s = makeBalloonShape();
    Graphics2D g2 = (Graphics2D) g.create();
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_ON);
    g2.setColor(getBackground());
    g2.fill(s);
    g2.dispose();
    super.paintComponent(g);
  }

  private Shape makeBalloonShape() {
    int w = getWidth() - 1;
    int h = getHeight() - TRI_HEIGHT - 1;
    int r = 10;
    int cx = getWidth() / 2;
    Polygon triangle = new Polygon();
    triangle.addPoint(cx - TRI_HEIGHT, h);
    triangle.addPoint(cx, h + TRI_HEIGHT);
    triangle.addPoint(cx + TRI_HEIGHT, h);
    Area area = new Area(new RoundRectangle2D.Float(0, 0, w, h, r, r));
    area.add(new Area(triangle));
    return area;
  }
}

// ...
@Override public String getToolTipText(MouseEvent e) {
  Point p = e.getPoint();
  int idx = locationToIndex(p);
  Rectangle rect = getCellBounds(idx, idx);
  if (idx < 0 || !rect.contains(p.x, p.y)) {
    return null;
  }
  Contribution value = getModel().getElementAt(idx);
  String act = value.activity == 0 ? "No" : Objects.toString(value.activity);
  return "<html>" + act + " contribution <span style='color:#C8C8C8'> on "
      + value.date.toString();
}

@Override public Point getToolTipLocation(MouseEvent e) {
  Point p = e.getPoint();
  int i = locationToIndex(p);
  Rectangle rect = getCellBounds(i, i);

  String toolTipText = getToolTipText(e);
  if (Objects.nonNull(toolTipText)) {
    JToolTip tip = createToolTip();
    tip.setTipText(toolTipText);
    Dimension d = tip.getPreferredSize();
    int gap = 2;
    return new Point((int) (rect.getCenterX() - d.getWidth() / 2d),
                     rect.y - d.height - gap);
  }
  return null;
}

@Override public JToolTip createToolTip() {
  if (tip == null) {
    tip = new BalloonToolTip();
    tip.setComponent(this);
  }
  return tip;
}

References

• Change the shape of JToolTip to balloon
• Create Week Calendar in JList and display contribution activity heatmap
• Make JToolTip translucent, and change its shape and display position(Japanese)

Draw a color wheel on JPanel

• download example.jar
• download src.zip
• repository

Code

// Colors: a Color Dialog | Java Graphics
// https://javagraphics.blogspot.com/2007/04/jcolorchooser-making-alternative.html
private BufferedImage updateImage() {
  BufferedImage image = new BufferedImage(SIZE, SIZE, BufferedImage.TYPE_INT_ARGB);
  int[] row = new int[SIZE];
  float size = (float) SIZE;
  float radius = size / 2f;
  for (int yidx = 0; yidx < SIZE; yidx++) {
    float y = yidx - radius;
    for (int xidx = 0; xidx < SIZE; xidx++) {
      float x = xidx - radius;
      double theta = Math.atan2(y, x) - 3d * Math.PI / 2d;
      if (theta < 0) {
        theta += 2d * Math.PI;
      }
      double r = Math.hypot(x, y); // Math.sqrt(x * x + y * y);
      float hue = (float) (theta / (2d * Math.PI));
      float sat = Math.min((float) (r / radius), 1f);
      float bri = 1f;
      row[xidx] = Color.HSBtoRGB(hue, sat, bri);
    }
    image.getRaster().setDataElements(0, yidx, SIZE, 1, row);
  }
  return image;
}

// campbell: Java 2D Trickery: Soft Clipping Blog | Oracle Community
// https://community.oracle.com/blogs/campbell/2006/07/19/java-2d-trickery-soft-clipping
GraphicsConfiguration gc = g2.getDeviceConfiguration();
BufferedImage buf = gc.createCompatibleImage(s, s, Transparency.TRANSLUCENT);
Graphics2D g2d = buf.createGraphics();

g2d.setComposite(AlphaComposite.Src);
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.fill(new Ellipse2D.Float(0f, 0f, s, s));

g2d.setComposite(AlphaComposite.SrcAtop);
g2d.drawImage(colorWheelImage, 0, 0, null);
g2d.dispose();

g2.drawImage(buf, null, (getWidth() - s) / 2, (getHeight() - s) / 2);
g2.dispose();

References

• Colors: a Color Dialog | Java Graphics
• campbell: Java 2D Trickery: Soft Clipping Blog | Oracle Community
• Draw a color wheel on JPanel(Japanese)