Swing/ProgressComboBox の変更点

• 追加された行はこの色です。
• 削除された行はこの色です。
• Swing/ProgressComboBox へ行く。
• Swing/ProgressComboBox の差分を削除

---
category: swing
folder: ProgressComboBox
title: JComboBox内にJProgressBarを表示
tags: [JComboBox, ListCellRenderer, JProgressBar, SwingWorker]
author: aterai
pubdate: 2011-09-05T17:17:06+09:00
description: JComboBox内にJProgressBarを設定して進捗を表示します。
image: https://lh6.googleusercontent.com/-wtOABuv6qdQ/TmR3t1oq-qI/AAAAAAAABBg/jbHLwwMR1gc/s800/ProgressComboBox.png
hreflang:
    href: https://java-swing-tips.blogspot.com/2011/09/jprogressbar-in-jcombobox.html
    lang: en
---
* Summary [#summary]
`JComboBox`内に`JProgressBar`を設定して進捗を表示します。

#download(https://lh6.googleusercontent.com/-wtOABuv6qdQ/TmR3t1oq-qI/AAAAAAAABBg/jbHLwwMR1gc/s800/ProgressComboBox.png)

* Source Code Examples [#sourcecode]
#code(link){{
class ProgressCellRenderer extends DefaultListCellRenderer {
  private final JProgressBar bar = new JProgressBar() {
    @Override public Dimension getPreferredSize() {
      return ProgressCellRenderer.this.getPreferredSize();
    }
  };

  @Override public Component getListCellRendererComponent(
      JList list, Object value, int index,
      boolean isSelected, boolean cellHasFocus) {
    if (index < 0 && worker != null && !worker.isDone()) {
      bar.setFont(list.getFont());
      bar.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 0));
      bar.setValue(count);
      return bar;
    } else {
      return super.getListCellRendererComponent(
        list, value, index, isSelected, cellHasFocus);
    }
  }

  @Override public void updateUI() {
    super.updateUI();
    if (bar != null) {
      SwingUtilities.updateComponentTreeUI(bar);
    }
  }
}
}}

* Description [#explanation]
* Description [#description]
上記のサンプルでは、`index`が`-1`(アイテムリストのインデックスではない)の場合は`JProgressBar`を返すリストセルレンダラーを`JComboBox`に設定して進捗を表示しています。

- ロードボタンが押されたら以下のような`SwingWorker`で`JComboBox`にアイテムを追加

#code{{
button = new JButton(new AbstractAction("load") {
  @Override public void actionPerformed(ActionEvent e) {
    button.setEnabled(false);
    combo.setEnabled(false);
    combo.removeAllItems();
    worker = new SwingWorker<String, String>() {
      private int max = 30;
      @Override public String doInBackground() throws InterruptedException {
        int current = 0;
        while (current <= max && !isCancelled()) {
          Thread.sleep(50);
          // setProgress(100 * current / max);
          count = 100 * current / max;
          publish("test: "+current);
          current++;
        }
        return "Done";
      }

      @Override protected void process(List<String> chunks) {
        DefaultComboBoxModel m = (DefaultComboBoxModel) combo.getModel();
        for (String s: chunks) {
          m.addElement(s);
        }
        combo.setSelectedIndex(-1);
        combo.repaint();
      }

      @Override public void done() {
        String text = null;
        if (!isCancelled()) {
          combo.setSelectedIndex(0);
        }
        combo.setEnabled(true);
        button.setEnabled(true);
        count = 0;
      }
    };
    worker.execute();
  }
});
}}

* Reference [#reference]
- [https://docs.oracle.com/javase/jp/8/docs/api/javax/swing/DefaultListCellRenderer.html DefaultListCellRenderer (Java Platform SE 8)]

* Comment [#comment]
#comment
#comment