configurablemenu.java

本系统是用 java 语言实现的一个 Email客户端

package net.suberic.util.gui;
import javax.swing.*;
import net.suberic.util.VariableBundle;
import java.util.Hashtable;
import java.util.StringTokenizer;
import java.util.MissingResourceException;
import javax.swing.Action;

/**
 * This is a JMenu which implements the ConfigurableUI interface, and
 * therefore may be dynamically created using a VariableBundle and key,
 * and updated using an array of Actions.
 */

public class ConfigurableMenu extends JMenu implements ConfigurableUI {

  // the latest commands list.  i'm storing this for now because i
  // can't do a JButton.removeActionListeners().

  protected Hashtable commands = new Hashtable();

  public ConfigurableMenu() {
    super();
  }

  /**
   * This creates a new ConfigurableMenu using the menuID as the
   * configuration key, and vars as the source for the values of all the
   * properties.
   *
   * If menuID doesn't exist in vars, then this returns an empty
   * Menu.
   */

  public ConfigurableMenu(String menuID, VariableBundle vars) {
    super();

    configureComponent(menuID, vars);
  }

  /**
   * This configures the Menu using the given menuID and
   * VariableBundle.
   *
   * As defined in interface net.suberic.util.gui.ConfigurableUI.
   */

  public void configureComponent(String key, VariableBundle vars) {
    StringTokenizer iKeys = null;
    try {
      iKeys = new StringTokenizer(vars.getProperty(key), ":");
    } catch (MissingResourceException mre) {
      mre.printStackTrace();
      try {
        System.err.println(vars.getProperty("error.NoSuchResource") + " " + mre.getKey());
      } catch (MissingResourceException mretwo) {
        System.err.println("Unable to load resource " + mre.getKey());
        return;
      }
      return;
    }
    String currentToken;

    try {
      setText(vars.getProperty(key + ".Label"));
    } catch (MissingResourceException mre) {
    }

    while (iKeys.hasMoreTokens()) {
      currentToken=iKeys.nextToken();
      if (currentToken.equals("-")) {
        this.addSeparator();
      } else {
        JMenuItem mi = createMenuItem(key, currentToken, vars);
        this.add(mi);
      }
    }

    String keyBinding = vars.getProperty(key + ".KeyBinding", "");
    if (!keyBinding.equals("")) {
      this.setMnemonic(keyBinding.charAt(0));
    }

  }

  /**
   * And this actually creates the menu items themselves.
   */
  protected JMenuItem createMenuItem(String menuID, String menuItemID, VariableBundle vars) {
    // TODO:  should also make these undo-able.

    if (vars.getProperty(menuID + "." + menuItemID + ".class", "") == "") {

      if (vars.getProperty(menuID + "." + menuItemID, "") != "") {
        return new ConfigurableMenu(menuID + "." + menuItemID, vars);
      }

      JMenuItem mi;
      try {
        mi = new JMenuItem(vars.getProperty(menuID + "." + menuItemID + ".Label"));
      } catch (MissingResourceException mre) {
        mi = new JMenuItem(menuItemID);
      }

      java.net.URL url = null;

      try {
        url = this.getClass().getResource(vars.getProperty(menuID + "." + menuItemID + ".Image"));
      } catch (MissingResourceException mre) {
      }

      if (url != null) {
        mi.setHorizontalTextPosition(JButton.RIGHT);
        mi.setIcon(new ImageIcon(url));
      }

      String cmd = vars.getProperty(menuID + "." + menuItemID + ".Action", menuItemID);

      mi.setActionCommand(cmd);

      String keyBinding = vars.getProperty(menuID + "." + menuItemID + ".KeyBinding", "");
      if (!keyBinding.equals(""))
        mi.setMnemonic(keyBinding.charAt(0));

      String accelBinding = vars.getProperty(menuID + "." + menuItemID + ".Accelerator", "");
      if (!accelBinding.equals("")) {
        mi.setAccelerator(KeyStroke.getKeyStroke(accelBinding));
      }

      return mi;
    } else {
      // this means that we have a submenu.
      ConfigurableMenu m;

      if (vars.getProperty(menuID + "." + menuItemID + ".class", "").equals("")) {
        m = new ConfigurableMenu(menuID + "." + menuItemID, vars);

      } else {
        // this means we're using a custom Menu.

        try {
          Class menuClass = Class.forName(vars.getProperty(menuID + "." + menuItemID + ".class", "net.suberic.util.gui.ConfigurableMenu"));
          m = (ConfigurableMenu) menuClass.newInstance();
          m.configureComponent(menuID + "." + menuItemID, vars);
        } catch (Exception e) {
          e.printStackTrace();
          // if we get any errors, just create a plain
          // ConfigurableMenu.
          m = new ConfigurableMenu(menuID + "." + menuItemID, vars);
        }
      }

      return m;

    }
  }

  /**
   * As defined in net.suberic.util.gui.ConfigurableUI
   */
  public void setActive(javax.swing.Action[] newActions) {
    Hashtable tmpHash = new Hashtable();
    if (newActions != null && newActions.length > 0) {
      for (int i = 0; i < newActions.length; i++) {
        String cmdName = (String)newActions[i].getValue(Action.NAME);
        tmpHash.put(cmdName, newActions[i]);
      }
    }
    setActive(tmpHash);
  }

  /**
   * As defined in net.suberic.util.gui.ConfigurableUI
   */
  public void setActive(Hashtable newCommands) {
    clearListeners();
    commands = newCommands;
    setActiveMenuItems();
  }

  protected void setActiveMenuItems() {
    for (int j = 0; j < getItemCount(); j++) {
      if (getItem(j) instanceof ConfigurableMenu) {
        ((ConfigurableMenu)getItem(j)).setActive(commands);
      } else {
        JMenuItem mi = getItem(j);
        Action a = getAction(mi.getActionCommand());
        if (a != null) {
          //mi.removeActionListener(a);
          mi.addActionListener(a);
          mi.setEnabled(true);
        } else {
          mi.setEnabled(false);
        }
      }
    }
  }

  /**
   * This clears all of the current listeners on the Menu.
   */

  private void clearListeners() {
    for (int j = 0; j < getItemCount(); j++) {
      if (getItem(j) instanceof ConfigurableMenu) {
        // we don't have to clear the listeners here because
        // it will be done in setActive().
        ;
      } else {
        JMenuItem mi = getItem(j);
        Action a = getAction(mi.getActionCommand());
        if (a != null) {
          mi.removeActionListener(a);
        }
      }
    }
  }

  /**
   * This gets an action from the supported commands.  If there is no
   * supported action, it returns null
   */

  public Action getAction(String command) {
    return (Action)commands.get(command);
  }


}