Java Swing Tips

2015/02/25

Logging into the JTextArea

Code

Logger logger = Logger.getLogger(TextAreaLogger.TEST.getClass().getName());
logger.setUseParentHandlers(false);
OutputStream os = new TextAreaOutputStream(new JTextArea());
logger.addHandler(new TextAreaHandler(os));
logger.info("test, TEST");

//...
class TextAreaHandler extends StreamHandler {
  public TextAreaHandler(OutputStream os) {
    super();
    configure();
    setOutputStream(os);
  }

  private void configure() {
    setFormatter(new SimpleFormatter());
    try {
      setEncoding("UTF-8");
    } catch (IOException ex) {
      try {
        setEncoding(null);
      } catch (IOException ex2) {
        // doing a setEncoding with null should always work.
        // assert false;
        ex2.printStackTrace();
      }
    }
  }

  // @see java/util/logging/ConsoleHandler.java
  @Override public void publish(LogRecord record) {
    super.publish(record);
    flush();
  }

  @Override public void close() {
    flush();
  }
}

References

2015/01/29

Show/Hide PasswordField

Code

JPasswordField pf = new JPasswordField(24);
pf.setText("abcdefghijklmn");
pf.setAlignmentX(Component.RIGHT_ALIGNMENT);
AbstractDocument doc = (AbstractDocument) pf.getDocument();
doc.setDocumentFilter(new ASCIIOnlyDocumentFilter());

AbstractButton b = new JToggleButton(new AbstractAction() {
  @Override public void actionPerformed(ActionEvent e) {
    AbstractButton c = (AbstractButton) e.getSource();
    Character ec = c.isSelected() ? 0
        : (Character) UIManager.get("PasswordField.echoChar");
    pf.setEchoChar(ec);
  }
});
b.setFocusable(false);
b.setOpaque(false);
b.setContentAreaFilled(false);
b.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 4));
b.setAlignmentX(Component.RIGHT_ALIGNMENT);
b.setAlignmentY(Component.CENTER_ALIGNMENT);
b.setIcon(new ColorIcon(Color.GREEN));
b.setRolloverIcon(new ColorIcon(Color.BLUE));
b.setSelectedIcon(new ColorIcon(Color.RED));
b.setRolloverSelectedIcon(new ColorIcon(Color.ORANGE));

JPanel panel = new JPanel() {
  @Override public boolean isOptimizedDrawingEnabled() {
    return false;
  }
};
panel.setLayout(new OverlayLayout(panel));
panel.add(b);
panel.add(pf);

References

Show/Hide PasswordField using CardLayout(Japanese)

2014/12/31

Draggable and sortable JPanels

Code

class RearrangingHandler extends MouseAdapter {
  private static final Rectangle R1 = new Rectangle();
  private static final Rectangle R2 = new Rectangle();
  private final Rectangle prevRect = new Rectangle();
  private final int gestureMotionThreshold = DragSource.getDragThreshold();
  private final JWindow window = new JWindow();
  private final Point startPt = new Point();
  private int index = -1;
  private Component draggingComponent;
  private Component gap;
  private final Point dragOffset = new Point();

  public RearrangingHandler() {
    super();
    window.setBackground(new Color(0x0, true));
  }

  @Override public void mousePressed(MouseEvent e) {
    if (((JComponent) e.getComponent()).getComponentCount() <= 1) {
      startPt.setLocation(0, 0);
    } else {
      startPt.setLocation(e.getPoint());
    }
  }

  private void startDragging(JComponent parent, Point pt) {
    Component c = parent.getComponentAt(pt);
    index = parent.getComponentZOrder(c);
    if (Objects.equals(c, parent) || index < 0) {
      return;
    }
    draggingComponent = c;
    Dimension d = draggingComponent.getSize();

    Point dp = draggingComponent.getLocation();
    dragOffset.setLocation(pt.x - dp.x, pt.y - dp.y);

    gap = Box.createRigidArea(d);
    swapComponentLocation(parent, c, gap, index);

    window.add(draggingComponent);
    // window.setSize(d);
    window.pack();

    updateWindowLocation(pt, parent);
    window.setVisible(true);
  }

  private void updateWindowLocation(Point pt, JComponent parent) {
    if (window.isVisible() && Objects.nonNull(draggingComponent)) {
      Point p = new Point(pt.x - dragOffset.x, pt.y - dragOffset.y);
      SwingUtilities.convertPointToScreen(p, parent);
      window.setLocation(p);
    }
  }

  private int getTargetIndex(Rectangle r, Point pt, int i) {
    int ht2 = (int) (.5 + r.height * .5);
    R1.setBounds(r.x, r.y, r.width, ht2);
    R2.setBounds(r.x, r.y + ht2, r.width, ht2);
    if (R1.contains(pt)) {
      prevRect.setBounds(R1);
      return i - 1 > 0 ? i : 0;
    } else if (R2.contains(pt)) {
      prevRect.setBounds(R2);
      return i;
    }
    return -1;
  }

  private static void swapComponentLocation(
      Container parent, Component remove, Component add, int idx) {
    parent.remove(remove);
    parent.add(add, idx);
    parent.revalidate();
    parent.repaint();
  }

  @Override public void mouseDragged(MouseEvent e) {
    Point pt = e.getPoint();
    JComponent parent = (JComponent) e.getComponent();
    if (Objects.isNull(draggingComponent)) {
      if (startPt.distance(pt) > gestureMotionThreshold) {
        startDragging(parent, pt);
      }
      return;
    }
    updateWindowLocation(pt, parent);

    if (prevRect.contains(pt)) {
      return;
    }
    for (int i = 0; i < parent.getComponentCount(); i++) {
      Component c = parent.getComponent(i);
      Rectangle r = c.getBounds();
      if (Objects.equals(c, gap) && r.contains(pt)) {
        return;
      }
      int tgt = getTargetIndex(r, pt, i);
      if (tgt >= 0) {
        swapComponentLocation(parent, gap, gap, tgt);
        return;
      }
    }
    // System.out.println("outer");
    parent.remove(gap);
    parent.revalidate();
  }

  @Override public void mouseReleased(MouseEvent e) {
    startPt.setLocation(0, 0);
    dragOffset.setLocation(0, 0);
    prevRect.setBounds(0, 0, 0, 0);
    window.setVisible(false);

    Point pt = e.getPoint();
    JComponent parent = (JComponent) e.getComponent();
    Component cmp = draggingComponent;
    draggingComponent = null;

    for (int i = 0; i < parent.getComponentCount(); i++) {
      Component c = parent.getComponent(i);
      if (Objects.equals(c, gap)) {
        swapComponentLocation(parent, gap, cmp, i);
        return;
      }
      int tgt = getTargetIndex(c.getBounds(), pt, i);
      if (tgt >= 0) {
        swapComponentLocation(parent, gap, cmp, tgt);
        return;
      }
    }
    if (parent.getParent().getBounds().contains(pt)) {
      swapComponentLocation(parent, gap, cmp, parent.getComponentCount());
    } else {
      swapComponentLocation(parent, gap, cmp, index);
    }
  }
}

References

2014/11/27

Make a transparent JTree and translucent selection background

Code

class TransparentTreeCellRenderer extends DefaultTreeCellRenderer {
  @Override public Component getTreeCellRendererComponent(
          JTree tree, Object value, boolean isSelected, boolean expanded,
          boolean leaf, int row, boolean hasFocus) {
    JComponent c = (JComponent) super.getTreeCellRendererComponent(
          tree, value, isSelected, expanded, leaf, row, hasFocus);
    c.setOpaque(false);
    return c;
  }
  private final Color ALPHA_OF_ZERO = new Color(0, true);
  @Override public Color getBackgroundNonSelectionColor() {
    return ALPHA_OF_ZERO;
  }
  @Override public Color getBackgroundSelectionColor() {
    return ALPHA_OF_ZERO;
  }
}

class TranslucentTreeCellRenderer extends TransparentTreeCellRenderer {
  private final Color backgroundSelectionColor = new Color(100, 100, 255, 100);

  @Override public Color getBackgroundSelectionColor() {
    return backgroundSelectionColor;
  }
}

References

Make a transparent JTree and translucent selection background(Japanese)

2014/10/29

JMenuItem accelerator text alignment

Code

RightAcc

public static void paintAccText(
  Graphics g, MenuItemLayoutHelper lh, MenuItemLayoutHelper.LayoutResult lr,
  Color disabledForeground, Color acceleratorForeground,
  Color acceleratorSelectionForeground) {
  if (!lh.getAccText().equals("")) {
    ButtonModel model = lh.getMenuItem().getModel();
    g.setFont(lh.getAccFontMetrics().getFont());
    if (!model.isEnabled()) {
      // *** paint the accText disabled
      if (disabledForeground != null) {
        g.setColor(disabledForeground);
        SwingUtilities2.drawString(
          lh.getMenuItem(), g, lh.getAccText(),
          lr.getAccRect().x,
          lr.getAccRect().y + lh.getAccFontMetrics().getAscent());
      } else {
        g.setColor(lh.getMenuItem().getBackground().brighter());
        SwingUtilities2.drawString(
          lh.getMenuItem(), g, lh.getAccText(),
          lr.getAccRect().x,
          lr.getAccRect().y + lh.getAccFontMetrics().getAscent());
        g.setColor(lh.getMenuItem().getBackground().darker());
        SwingUtilities2.drawString(
          lh.getMenuItem(), g, lh.getAccText(),
          lr.getAccRect().x - 1,
          lr.getAccRect().y + lh.getFontMetrics().getAscent() - 1);
      }
    } else {
      // *** paint the accText normally
      if (model.isArmed() ||
          (lh.getMenuItem() instanceof JMenu && model.isSelected())) {
        g.setColor(acceleratorSelectionForeground);
      } else {
        g.setColor(acceleratorForeground);
      }
      SwingUtilities2.drawString(
        lh.getMenuItem(), g, lh.getAccText(),
        //lr.getAccRect().x, // ++++++++++++++++++++
        lh.getViewRect().x + lh.getViewRect().width
        - lh.getMenuItem().getIconTextGap() - lr.getAccRect().width,
        // ++++++++++++++++++++
        lr.getAccRect().y + lh.getAccFontMetrics().getAscent());
    }
  }
}

EastAcc

public static void paintAccText(
private static JMenuItem makeMenuItem2(JMenuItem mi) {
  final JLabel label = new JLabel(MenuItemUIHelper.getAccText(mi, "+"));
  label.setOpaque(true);
  JMenuItem item = new JMenuItem(mi.getText()) {
    @Override public void updateUI() {
      super.updateUI();
      if (getUI() instanceof WindowsMenuItemUI) {
        setUI(new WindowsMenuItemUI() {
          @Override protected void installDefaults() {
            super.installDefaults();
            acceleratorForeground = UIManager.getColor("MenuItem.background");
            acceleratorSelectionForeground = acceleratorForeground;
          }
        });
      }
    }
  };

  GridBagConstraints c = new GridBagConstraints();
  item.setLayout(new GridBagLayout());
  c.gridheight = 1;
  c.gridwidth  = 1;
  c.gridy = 0;
  c.gridx = 0;
  c.insets = new Insets(0, 0, 0, 4);

  c.weightx = 1d;
  c.fill = GridBagConstraints.HORIZONTAL;
  item.add(Box.createHorizontalGlue(), c);
  c.gridx = 1;
  c.fill = GridBagConstraints.NONE;
  c.weightx = 0d;
  c.anchor = GridBagConstraints.EAST;
  item.add(label, c);

  item.setMnemonic(mi.getMnemonic());
  item.setAccelerator(mi.getAccelerator());
  return item;
}

References

JMenuItem accelerator text alignment(Japanese)

Google Tag Manager

2015/02/25

Logging into the JTextArea

Code

References

2015/01/29

Show/Hide PasswordField

Code

References

2014/12/31

Draggable and sortable JPanels

Code

References

2014/11/27

Make a transparent JTree and translucent selection background

Code

References

2014/10/29

JMenuItem accelerator text alignment

Code

RightAcc

EastAcc

References