platformcanvas.samsung

开发j2me 手机程序必须的用到的。文件较小

package com.jmobilecore.ui.core;

import javax.microedition.lcdui.*;

/**
 * Provides platform dependent settings for Samsung platform
 *
 * @author Greg Gridin
 */
abstract public class PlatformCanvas extends Canvas {

    static public final byte PLATFORM_BARTEO = 1;
    static public final byte PLATFORM_LG = 2;
    static public final byte PLATFORM_MOTOROLA = 3;
    static public final byte PLATFORM_MOTOROLA_V = 4;
    static public final byte PLATFORM_NOKIA = 5;
    static public final byte PLATFORM_NOKIA_30 = 6;
    static public final byte PLATFORM_SIEMENS = 7;
    static public final byte PLATFORM_SAMSUNG = 8;
    static public final byte PLATFORM_SONYERICSSON = 9;
    static public final byte PLATFORM_SUN_WTK = 10;

    static public final byte PLATFORM = PLATFORM_SAMSUNG;

    /**
     * This class is created specifically for LG phones, which does not provide
     * key press codes for soft buttons in Canvas
     * This class imitates pressing of soft button key when corresponding command is received
     */
    class LGSoftKeyListener implements CommandListener {

        private Command leftCommand;
        private Command rightCommand;

        /**
         * Constructs new <code>LGSoftKeyListener</code> instance.
         *
         * @param leftCommand - Command for the left soft key
         * @param rightCommand - Command for the right soft key
         */
        public LGSoftKeyListener(Command leftCommand, Command rightCommand) {

            this.leftCommand = leftCommand;
            this.rightCommand = rightCommand;
        }

        /**
         * Imitates key press when correspondent command is received
         *
         * @param command - command event
         * @param display - displayable object
         */
        public void commandAction(Command command, Displayable display) {

          if (display==null || command==null) return;

          if (leftCommand != null && leftCommand.equals(command) && display instanceof ScreenCanvas) {
            ((ScreenCanvas)display).keyPressed(PlatformCanvas.KEY_SOFT_LEFT);
            return;
          }
          if (rightCommand != null && rightCommand.equals(command) && display instanceof ScreenCanvas) {
            ((ScreenCanvas)display).keyPressed(PlatformCanvas.KEY_SOFT_RIGHT);
            return;
          }
        }
      }  // class LGSoftKeyListener

    public PlatformCanvas() {

        Command leftCommand = new Command("", Command.CANCEL, 1);
        Command rightCommand = new Command("", Command.OK, 1);
        addCommand(leftCommand);
        addCommand(rightCommand);
        setCommandListener(new LGSoftKeyListener(leftCommand, rightCommand));
    }

    /**
     * The width in pixels of a screen
     */
    public static final int WIDTH;

    /**
     * The height in pixels of a screen
     */
    public static final int HEIGHT;

    /**
     * Indicated whether the phone has hardware support for double buffering for screen painting
     */
    public static final boolean DOUBLE_BUFFER = true;

    static {
        Canvas dummy = new Canvas() {
            public void paint(Graphics g) {
            }
        };
        WIDTH = dummy.getWidth();
        HEIGHT = dummy.getHeight();
        dummy = null;
    }

    /**
     * "No-key" key code
     */
    public static final int KEY_UNDEFINED = 0;

    /**
     * Key code for the UP game action.
     */
    public static final int KEY_UP = -1;

    /**
     * Key code for the LEFT game action.
     */
    public static final int KEY_LEFT = -3;

    /**
     * Key code for the RIGHT game action.
     */
    public static final int KEY_RIGHT = -4;

    /**
     * Key code for the DOWN game action.
     */
    public static final int KEY_DOWN = -2;

    /**
     * Key code for the FIRE game action.
     */
    public static final int KEY_FIRE = -5;

    /**
     * Key code for left soft key
     */
    public static final int KEY_SOFT_LEFT = -7;

    /**
     * Key code for right soft key
     */
    public static final int KEY_SOFT_RIGHT = -6;

    /**
     * Key code for PHONE_ON key (green button)
     */
    public static final int KEY_PHONE_ON = -10;

    /**
     * Key code for PHONE_OFF key (red button)
     */
    public static final int KEY_PHONE_OFF = -11;

    /**
     * Key code for CLEAR key
     */
    public static final int KEY_CLEAR = -8;

    /**
     * Key code for VOLUME UP key
     */
    public static final int KEY_VOLUME_UP = KEY_UNDEFINED;

    /**
     * Key code for VOLUME DOWN key
     */
    public static final int KEY_VOLUME_DOWN = KEY_UNDEFINED;

    /**
     * Key code for "fictitious" ENTER key
     * Some phones does not have FIRE button, we have to find out the replacement
     */
    public static final int KEY_ENTER = KEY_FIRE;

} // class PlatformCanvas