Focus Border of the previously selected tab in JTabbedPane is thinly displayed as history

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

Code

class LineFocusTabbedPane extends JTabbedPane {
  private transient ChangeListener listener;

  protected LineFocusTabbedPane() {
    super();
  }

  @Override public void updateUI() {
    removeChangeListener(listener);
    UIManager.put("TabbedPane.tabInsets", new InsetsUIResource(1, 4, 0, 4));
    UIManager.put("TabbedPane.selectedTabPadInsets", new InsetsUIResource(1, 1, 1, 1));
    UIManager.put("TabbedPane.tabAreaInsets", new InsetsUIResource(3, 2, 0, 2));
    UIManager.put("TabbedPane.selectedLabelShift", 0);
    UIManager.put("TabbedPane.labelShift", 0);
    UIManager.put("TabbedPane.focus", new ColorUIResource(new Color(0x0, true)));
    super.updateUI();
    listener = new TabSelectionListener();
    addChangeListener(listener);
    setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
  }

  @Override public void insertTab(String title, Icon icon, Component c, String tip, int index) {
    super.insertTab(title, icon, c, tip, index);
    JLabel label = new JLabel(title, icon, SwingConstants.CENTER);
    setTabComponentAt(index, label);
  }
}

class TabSelectionListener implements ChangeListener {
  private static final Color ALPHA_ZERO = new Color(0x0, true);
  private static final Color SELECTION_COLOR = new Color(0x00_AA_FF);
  private static final Color PREV_COLOR = new Color(0x48_00_AA_FF, true);
  private int prev = -1;

  @Override public void stateChanged(ChangeEvent e) {
    JTabbedPane tabbedPane = (JTabbedPane) e.getSource();
    if (tabbedPane.getTabCount() <= 0) {
      return;
    }
    int idx = tabbedPane.getSelectedIndex();
    for (int i = 0; i < tabbedPane.getTabCount(); i++) {
      Component tab = tabbedPane.getTabComponentAt(i);
      if (tab instanceof JComponent) {
        Color color;
        if (i == idx) {
          color = SELECTION_COLOR;
        } else if (i == prev) {
          color = PREV_COLOR;
        } else {
          color = ALPHA_ZERO;
        }
        ((JComponent) tab).setBorder(BorderFactory.createMatteBorder(3, 0, 0, 0, color));
      }
    }
    prev = idx;
  }
}

References

• Focus Border of the previously selected tab in JTabbedPane is thinly displayed as history(Japanese)
• Java Swing Tips: Change the selection focus Border of JTabbedPane to underline

Change the selection focus Border of JTabbedPane to underline

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

Code

class UnderlineFocusTabbedPane extends JTabbedPane {
  private static final Border DEFAULT_BORDER =
      BorderFactory.createMatteBorder(0, 0, 3, 0, new Color(0x0, true));
  private static final Border SELECTED_BORDER =
      BorderFactory.createMatteBorder(0, 0, 3, 0, new Color(0x00_AA_FF));

  protected UnderlineFocusTabbedPane() {
    super();
  }

  @Override public void updateUI() {
    super.updateUI();
    // setFocusable(false);
    if (getUI() instanceof WindowsTabbedPaneUI) {
      setUI(new WindowsTabbedPaneUI() {
        @Override protected void paintFocusIndicator(
            Graphics g, int tabPlacement, Rectangle[] rects, int tabIndex,
            Rectangle iconRect, Rectangle textRect, boolean isSelected) {
          super.paintFocusIndicator(g, tabPlacement, rects, tabIndex, iconRect, textRect, false);
        }
      });
    } else {
      setUI(new BasicTabbedPaneUI() {
        @Override protected void paintFocusIndicator(
            Graphics g, int tabPlacement, Rectangle[] rects, int tabIndex,
            Rectangle iconRect, Rectangle textRect, boolean isSelected) {
          super.paintFocusIndicator(g, tabPlacement, rects, tabIndex, iconRect, textRect, false);
        }
      });
    }
    addChangeListener(e -> {
      JTabbedPane tabbedPane = (JTabbedPane) e.getSource();
      if (tabbedPane.getTabCount() <= 0) {
        return;
      }
      int idx = tabbedPane.getSelectedIndex();
      for (int i = 0; i < tabbedPane.getTabCount(); i++) {
        Component c = tabbedPane.getTabComponentAt(i);
        if (c instanceof JComponent) {
          ((JComponent) c).setBorder(i == idx ? SELECTED_BORDER : DEFAULT_BORDER);
        }
      }
    });
  }

  @Override public void insertTab(
      String title, Icon icon, Component component, String tip, int index) {
    super.insertTab(title, icon, component, tip, index);
    JLabel label = new JLabel(title, icon, SwingConstants.CENTER);
    setTabComponentAt(index, label);
  }
}

References

• Change the selection focus Border of JTabbedPane to underline(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)

The JRadioButton that is currently selected in the ButtonGroup set as the default focus component

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

Code

buttons.setFocusTraversalPolicyProvider(true);
buttons.setFocusTraversalPolicy(new LayoutFocusTraversalPolicy() {
  @Override public Component getDefaultComponent(Container focusCycleRoot) {
    ButtonModel selection = bg.getSelection();
    for (Component c: focusCycleRoot.getComponents()) {
      JRadioButton r = (JRadioButton) c;
      if (r.getModel().equals(selection)) {
        return r;
      }
    }
    return super.getDefaultComponent(focusCycleRoot);
  }
});

References

• [JDK-8033699] Incorrect radio button behavior - Java Bug System
• [JDK-8154043] Fields not reachable anymore by tab-key, because of new tabbing behaviour of radio button groups. - Java Bug System
• java - Get the focus in a ButtonGroup of JRadioButtons to go to the currently selected item instead of first - Stack Overflow
• The JRadioButton that is currently selected in the ButtonGroup set as the default focus component (Japanese)

Change border of focused row in JTable

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

Code

enum Type { START, END }

class DotBorder extends EmptyBorder {
  private static final BasicStroke DASHED = new BasicStroke(
      1f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER,
      10f, new float[] {1f}, 0f);
  private static final Color DOT_COLOR = new Color(200, 150, 150);
  public final Set<Type> type = EnumSet.noneOf(Type.class);

  protected DotBorder(int top, int left, int bottom, int right) {
    super(top, left, bottom, right);
  }

  @Override public boolean isBorderOpaque() {
    return true;
  }

  @Override public void paintBorder(
      Component c, Graphics g, int x, int y, int w, int h) {
    Graphics2D g2 = (Graphics2D) g.create();
    g2.translate(x, y);
    g2.setPaint(DOT_COLOR);
    g2.setStroke(DASHED);
    if (type.contains(Type.START)) {
      g2.drawLine(0, 0, 0, h);
    }
    if (type.contains(Type.END)) {
      g2.drawLine(w - 1, 0, w - 1, h);
    }
    if (c.getBounds().x % 2 == 0) {
      g2.drawLine(0, 0, w, 0);
      g2.drawLine(0, h - 1, w, h - 1);
    } else {
      g2.drawLine(1, 0, w, 0);
      g2.drawLine(1, h - 1, w, h - 1);
    }
    g2.dispose();
  }
}

References

• Change border of focused row in JTable(Japanese)