The QuickNotepadOptionPane Class
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## The QuickNotepadOptionPane Class

Using the default implementation provided by `AbstractOptionPane` reduces the preparation of an option pane to two principal tasks: writing a `_init()` method to layout and initialize the pane, and writing a `_save()` method to commit any settings changed by user input. If a button on the option pane should trigger another dialog, such as a `JFileChooser` or jEdit's own enhanced `VFSFileChooserDialog`, the option pane will also have to implement the `ActionListener` interface to display additional components.

The QuickNotepad plugin has only three options to set: the path name of the file that will store the notepad text, the visibility of the path name on the tool bar, and the notepad's display font. Using the shortcut methods of the plugin API, the implementation of `_init()` looks like this:

    public class QuickNotepadOptionPane extends AbstractOptionPane
          implements ActionListener
    {
        private JTextField pathName;
        private JButton pickPath;
        private FontSelector font;

        ...

        public void _init()
        {
            showPath = new JCheckBox(jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX
                + "show-filepath.title"),
            jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX +  "show-filepath")
                .equals("true"));
            addComponent(showPath);

            pathName = new JTextField(jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX
                + "filepath"));
            JButton pickPath = new JButton(jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX
                + "choose-file"));
            pickPath.addActionListener(this);

            JPanel pathPanel = new JPanel(new BorderLayout(0, 0));
            pathPanel.add(pathName, BorderLayout.CENTER);
            pathPanel.add(pickPath, BorderLayout.EAST);

            addComponent(jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX + "file"),
                pathPanel);

            font = new FontSelector(makeFont());
            addComponent(jEdit.getProperty(
                QuickNotepadPlugin.OPTION_PREFIX + "choose-font"),
                font);
        }

        ...

    }

Here we adopt the vertical arrangement offered by use of the `addComponent()` method with one embellishment. We want the first “row” of the option pane to contain a text field with the current notepad file path and a button that will trigger a file chooser dialog when pressed. To place both of them on the same line (along with an identifying label for the file option), we create a `JPanel` to contain both components and pass the configured panel to `addComponent()`.

The `_init()` method uses properties from the plugin's property file to provide the names of label for the components placed in the option pane. It also uses a property whose name begins with `PROPERTY_PREFIX` as a persistent data item - the path of the current notepad file. The elements of the notepad's font are also extracted from properties using a static method of the option pane class.

The `_save()` method extracts data from the user input components and assigns them to the plugin's properties. The implementation is straightforward:

    public void _save()
    {
        jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
            + "filepath", pathName.getText());
        Font _font = font.getFont();

        jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
            + "font", _font.getFamily());
        jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
            + "fontsize", String.valueOf(_font.getSize()));
        jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
            + "fontstyle", String.valueOf(_font.getStyle()));
        jEdit.setProperty(QuickNotepadPlugin.OPTION_PREFIX
            + "show-filepath", String.valueOf(showPath.isSelected()));
    }

The class has only two other methods, one to display a file chooser dialog in response to user action, and the other to construct a `Font` object from the plugin's font properties. They do not require discussion here.

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