mainmenu.java

一个关于沉船的J2ME小游戏

//
// Copyright 2002 Nokia Corporation
//
// THIS SOURCE CODE IS PROVIDED 'AS IS', WITH NO WARRANTIES WHATSOEVER,
// EXPRESS OR IMPLIED, INCLUDING ANY WARRANTY OF MERCHANTABILITY, FITNESS
// FOR ANY PARTICULAR PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE
// OR TRADE PRACTICE, RELATING TO THE SOURCE CODE OR ANY WARRANTY OTHERWISE
// ARISING OUT OF ANY PROPOSAL, SPECIFICATION, OR SAMPLE AND WITH NO
// OBLIGATION OF NOKIA TO PROVIDE THE LICENSEE WITH ANY MAINTENANCE OR
// SUPPORT. FURTHERMORE, NOKIA MAKES NO WARRANTY THAT EXERCISE OF THE
// RIGHTS GRANTED HEREUNDER DOES NOT INFRINGE OR MAY NOT CAUSE INFRINGEMENT
// OF ANY PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OWNED OR CONTROLLED
// BY THIRD PARTIES
//
// Furthermore, information provided in this source code is preliminary,
// and may be changed substantially prior to final release. Nokia Mobile
// Phones Ltd. retains the right to make changes to this source code at
// any time, without notice. This source code is provided for informational
// purposes only.
//
// Third-party brands and names are the property of their respective
// owners. Java(TM) and J2ME(TM) are registered trademarks of
// Sun Microsystems Inc.
//
// A non-exclusive, non-transferable, worldwide, limited license is hereby
// granted to the Licensee to download, print, reproduce and modify the
// source code. The licensee has the right to market, sell, distribute and
// make available the source code in original or modified form only when
// incorporated into the programs developed by the Licensee. No other
// license, express or implied, by estoppel or otherwise, to any other
// intellectual property rights is granted herein.
//


import javax.microedition.lcdui.*;


// The main menu is shown after the splash screen, or when the
// game screen has been temporarily paused (using the 'Back' command
// or a softkey in the (Canvas or FullCanvas) game screen).
// The main menu allows the user to start a new game, to continue
// playing an existing (paused) game, to change game settings,
// to find the instructions on how to play, etc.

class MainMenu
    extends List
    implements CommandListener
{
    private final BlitzMIDlet midlet;
    private final Dictionary dict;
    private boolean hasContinue = false;


    MainMenu(BlitzMIDlet midlet, Dictionary dict, GameEffects gameEffects, boolean cont)
    {
        super("DropShip", List.IMPLICIT);
        this.midlet = midlet;
        this.dict = dict;

        // The default main menu items are:
        //   - New game
        //   - Settings
        //   - Instructions
	  //	 - High Score
        //
        // There is one main menu item that may or may not be present:
        //   - Continue:
        //       It is added when a game starts (to handle game pauses),
        //       and is removed when a game ends (see methods addContinue
        //       and deleteContinue below).
        //
        // Exit is added as sofkey Command and not as a menu item.


        // add default menu items
        append(dict.getString(Dictionary.LABEL_NEWGAME), null);
        if (gameEffects.hasSoundCapability() ||
            gameEffects.hasVibrationCapability())
        {
            // The Settings item is only added if the device has Sound
            // and Vibration support, otherwise having a Settings menu
            // to change their values is useless.
            append(dict.getString(Dictionary.LABEL_SETTINGS), null);
        }
        append(dict.getString(Dictionary.LABEL_INSTRUCTIONS), null);
        append(dict.getString(Dictionary.LABEL_HISCORE), null);

        addCommand(new Command(dict.getString(Dictionary.LABEL_EXIT),
                               Command.EXIT, 1));
        setCommandListener(this);
	  if (cont) addContinue();
    }


    void addContinue()
    {
        // add Continue to the list of menu items, if not already present
        if (!hasContinue)
        {
            insert(0, dict.getString(Dictionary.LABEL_CONTINUE), null);
            hasContinue = true;
        }
    }


    void deleteContinue()
    {
        // remove 'Continue' from the list of menu items, if present
        if (hasContinue)
        {
            this.delete(0);
            hasContinue = false;
        }
    }


    void selectContinue()
    {
        if (hasContinue)
        {
            this.setSelectedIndex(0, true);
        }
    }


    public void commandAction(Command command, Displayable d)
    {
        if (command == List.SELECT_COMMAND)
        {
            String selected = getString(getSelectedIndex());

            if (selected.equals(dict.getString(Dictionary.LABEL_CONTINUE)))
            {
                midlet.mainMenuContinue();
            }
            else if (selected.equals(dict.getString(Dictionary.LABEL_NEWGAME)))
            {
                midlet.mainMenuNewGame(false);
            }
            else if (selected.equals(
                dict.getString(Dictionary.LABEL_SETTINGS)))
            {
                midlet.mainMenuSettings();
            }
            else if (selected.equals(dict.getString(Dictionary.LABEL_HISCORE)))
            {
                midlet.mainMenuHiScore();
            }
            else if (selected.equals(
                dict.getString(Dictionary.LABEL_INSTRUCTIONS)))
            {
                midlet.mainMenuInstructions();
            }
        }
        else
        {
            // the application code only adds one command: Exit
            midlet.mainMenuExit();
        }
    }
}