概要

JComboBoxEditorComponentJButtonJLabelなどを配置します。

サンプルコード

class ComboBoxLayout implements LayoutManager {
  private final JLabel label;
  private final JButton button;
  public ComboBoxLayout(JLabel label, JButton button) {
    this.label = label;
    this.button = button;
  }
  @Override public void addLayoutComponent(String name, Component comp) {
    /* not needed */
  }
  @Override public void removeLayoutComponent(Component comp) {
    /* not needed */
  }
  @Override public Dimension preferredLayoutSize(Container parent) {
    return parent.getPreferredSize();
  }
  @Override public Dimension minimumLayoutSize(Container parent) {
    return parent.getMinimumSize();
  }
  @Override public void layoutContainer(Container parent) {
    if (!(parent instanceof JComboBox)) {
      return;
    }
    JComboBox cb     = (JComboBox) parent;
    int width        = cb.getWidth();
    int height       = cb.getHeight();
    Insets insets    = cb.getInsets();
    int buttonHeight = height - insets.top - insets.bottom;
    int buttonWidth  = buttonHeight;
    int labelWidth   = buttonHeight;
    int loupeWidth; //   = buttonHeight;

    JButton arrowButton = (JButton) cb.getComponent(0);
    if (arrowButton != null) {
      Insets arrowInsets = arrowButton.getInsets();
      buttonWidth = arrowButton.getPreferredSize().width
        + arrowInsets.left + arrowInsets.right;
      arrowButton.setBounds(
          width - insets.right - buttonWidth,
          insets.top, buttonWidth, buttonHeight);
    }
    if (label != null) {
      Insets labelInsets = label.getInsets();
      labelWidth = label.getPreferredSize().width
        + labelInsets.left + labelInsets.right;
      label.setBounds(insets.left, insets.top, labelWidth, buttonHeight);
    }
    JButton rssButton = button;
    if (rssButton != null && rssButton.isVisible()) {
      Insets loupeInsets = rssButton.getInsets();
      loupeWidth = rssButton.getPreferredSize().width
        + loupeInsets.left + loupeInsets.right;
      rssButton.setBounds(
          width - insets.right - loupeWidth - buttonWidth,
          insets.top, loupeWidth, buttonHeight);
    } else {
      loupeWidth = 0;
    }

    Component editor = cb.getEditor().getEditorComponent();
    if (editor != null) {
      editor.setBounds(
          insets.left + labelWidth, insets.top,
          width  - insets.left - insets.right
                 - buttonWidth - labelWidth - loupeWidth,
          height - insets.top  - insets.bottom);
    }
  }
}
view all

解説

上記のサンプルでは、JComboBoxに独自のレイアウトマネージャーを設定して、内部にJButtonJLabelを配置しています。


RolloverIconは、元のアイコンに以下のようなフィルタを掛けて作成しています。

// RGBImageFilter を使用
private static ImageIcon makeFilteredImage(ImageIcon srcIcon) {
  RGBImageFilter filter = new SelectedImageFilter();
  FilteredImageSource fis = new FilteredImageSource(srcIcon.getImage().getSource(), filter);
  return new ImageIcon(Toolkit.getDefaultToolkit().createImage(fis));
}
class SelectedImageFilter extends RGBImageFilter {
  private static final float SCALE = 1.2f;
  @Override public int filterRGB(int x, int y, int argb) {
    //int a = (argb >> 24) & 0xff;
    int r = (int) Math.min(0xff, ((argb >> 16) & 0xff) * SCALE);
    int g = (int) Math.min(0xff, ((argb >>  8) & 0xff) * SCALE);
    int b = (int) Math.min(0xff, ((argb)       & 0xff) * SCALE);
    return (argb & 0xff000000) | (r << 16) | (g << 8) | (b);
  }
}

// RescaleOp を使用
private static ImageIcon makeFilteredImage2(ImageIcon srcIcon) {
  RescaleOp op = new RescaleOp(
      new float[] { 1.2f, 1.2f, 1.2f, 1f },
      new float[] { 0f, 0f, 0f, 0f }, null);
  BufferedImage img = new BufferedImage(
      srcIcon.getIconWidth(), srcIcon.getIconHeight(), BufferedImage.TYPE_INT_ARGB);
  Graphics g = img.getGraphics();
  //g.drawImage(srcIcon.getImage(), 0, 0, null);
  srcIcon.paintIcon(null, g, 0, 0);
  g.dispose();
  return new ImageIcon(op.filter(img, null));
}

参考リンク

コメント

  • EditorComponentに追加したJButtonをクリックすると例外が発生する場合があるバグを修正 -- aterai