J2ME框架之J4ME

package org.j4me.ui; import java.util.*; import javax.microedition.lcdui.*; import org.j4me.logging.*; /** * The <code>DeviceScreen</code> class is a base class for any screen that needs complete * control over how it is painted. It is based on and similar to the MIDP * <code>Canvas</code> class. * <p> * This class removes the following methods from the MIDP <code>Canvas</code> class: * <ul> * <li><code>isDoubleBuffered</code> - This class is always double buffered. * <li><code>hasPointerEvents</code> and <code>hasPointerMotionEvents</code> - There is * no use for this method. Implement the pointer event methods and * if the device has no pointer they will be ignored. * <li> - Same reason as <code>hasPointerEvents</code>. * <li><code>hasRepeatEvents</code> - This class always has key repeat events. * <li><code>getKeyName</code> - The application should define the names to make them * consistent across all devices. * <li><code>getKeyCode</code> - The key code is passed into the key event methods. * <li><code>getGameAction</code> - The game action is passed into the key event methods. * <li><code>sizeChanged</code> - This method is notoriously buggy and applications * should use <code>getWidth</code> and <code>getHeight</code> instead. * <li><code>getTicker</code> and <code>setTicker</code> - The ticker functionality has * not been implemented. * <li><code>addCommand</code>, <code>removeCommand</code>, and <code>setCommandListener</code> - * Menu options have been replaced with something that works across all * MIDP 2.0 devices. There are left and right menu options. See * <code>setMenuText</code> for details. * </ul> * * @see javax.microedition.lcdui.Canvas */ public abstract class DeviceScreen { /** * Constant for the <code>LEFT</code> game action. */ public static final int LEFT = -1 * javax.microedition.lcdui.Canvas.LEFT; /** * Constant for the <code>RIGHT</code> game action. */ public static final int RIGHT = -1 * javax.microedition.lcdui.Canvas.RIGHT; /** * Constant for the <code>UP</code> game action. */ public static final int UP = -1 * javax.microedition.lcdui.Canvas.UP; /** * Constant for the <code>DOWN</code> game action. */ public static final int DOWN = -1 * javax.microedition.lcdui.Canvas.DOWN; /** * Constant for the <code>FIRE</code> game action. */ public static final int FIRE = -1 * javax.microedition.lcdui.Canvas.FIRE; /** * Constant for the general purpose "A" game action. */ public static final int GAME_A = -1 * javax.microedition.lcdui.Canvas.GAME_A; /** * Constant for the general purpose "B" game action. */ public static final int GAME_B = -1 * javax.microedition.lcdui.Canvas.GAME_B; /** * Constant for the general purpose "C" game action. */ public static final int GAME_C = -1 * javax.microedition.lcdui.Canvas.GAME_C; /** * Constant for the general purpose "D" game action. */ public static final int GAME_D = -1 * javax.microedition.lcdui.Canvas.GAME_D; /** * <code>keyCode</code> for ITU-T key 0. * <p> * Constant value 48 is set to <code>KEY_NUM0</code>. */ public static final int KEY_NUM0 = javax.microedition.lcdui.Canvas.KEY_NUM0; /** * <code>keyCode</code> for ITU-T key 1. * <p> * Constant value 49 is set to <code>KEY_NUM1</code>. */ public static final int KEY_NUM1 = javax.microedition.lcdui.Canvas.KEY_NUM1; /** * <code>keyCode</code> for ITU-T key 2. * <p> * Constant value 50 is set to <code>KEY_NUM2</code>. */ public static final int KEY_NUM2 = javax.microedition.lcdui.Canvas.KEY_NUM2; /** * <code>keyCode</code> for ITU-T key 3. * <p> * Constant value 51 is set to <code>KEY_NUM3</code>. */ public static final int KEY_NUM3 = javax.microedition.lcdui.Canvas.KEY_NUM3; /** * <code>keyCode</code> for ITU-T key 4. * <p> * Constant value 52 is set to <code>KEY_NUM4</code>. */ public static final int KEY_NUM4 = javax.microedition.lcdui.Canvas.KEY_NUM4; /** * <code>keyCode</code> for ITU-T key 5. * <p> * Constant value 53 is set to <code>KEY_NUM5</code>. */ public static final int KEY_NUM5 = javax.microedition.lcdui.Canvas.KEY_NUM5; /** * <code>keyCode</code> for ITU-T key 6. * <p> * Constant value 54 is set to <code>KEY_NUM6</code>. */ public static final int KEY_NUM6 = javax.microedition.lcdui.Canvas.KEY_NUM6; /** * <code>keyCode</code> for ITU-T key 7. * <p> * Constant value 55 is set to <code>KEY_NUM7</code>. */ public static final int KEY_NUM7 = javax.microedition.lcdui.Canvas.KEY_NUM7; /** * <code>keyCode</code> for ITU-T key 8. * <p> * Constant value 56 is set to <code>KEY_NUM8</code>. */ public static final int KEY_NUM8 = javax.microedition.lcdui.Canvas.KEY_NUM8; /** * <code>keyCode</code> for ITU-T key 9. * <p> * Constant value 57 is set to <code>KEY_NUM9</code>. */ public static final int KEY_NUM9 = javax.microedition.lcdui.Canvas.KEY_NUM9; /** * <code>keyCode</code> for ITU-T key "pound" (#). * <p> * Constant value 35 is set to <code>KEY_POUND</code>. */ public static final int KEY_POUND = javax.microedition.lcdui.Canvas.KEY_POUND; /** * <code>keyCode</code> for ITU-T key "star" (*). * <p> * Constant value 42 is set to <code>KEY_STAR</code>. */ public static final int KEY_STAR = javax.microedition.lcdui.Canvas.KEY_STAR; /** * Constant for the left soft menu key found on MIDP 2.0 devices. */ public static final int MENU_LEFT = -21; /** * Constant for the right soft menu key found on MIDP 2.0 devices. */ public static final int MENU_RIGHT = -22; /** * The actual <code>Canvas</code> object that controls the device's screen. * This object wraps it. */ private final CanvasWrapper slave; /** * When <code>false</code> this class will paint the menu bar at the bottom * of the screen. When <code>true</code> it will not. */ private boolean fullScreenMode = false; /** * What is written as a title bar for this canvas. When this is <code>null</code> * no title bar will be written. To show the header without any text * set this to the empty string "". */ private String title; /** * The text for the left menu button. This is the negative side used * for canceling and going back to previous screens. */ private String leftMenu; /** * The text for the right menu button. This is the positive side used * for accepting input, invoking menus, and moving forward in the * application's state. */ private String rightMenu; /** * Implicitly called by derived classes to setup a new J4ME canvas. */ public DeviceScreen () { // Create a wrapper around the canvas. slave = new CanvasWrapper( this ); } /** * Returns the LCDUI <code>Canvas</code> wrapped by this screen. This is * required for some APIs. * * @return The <code>javax.microedition.lcdui.Canvas</code> wrapped by this screen. */ public Canvas getCanvas () { return slave; } /** * Makes this object take over the device's screen. * <p> * The previous screen will have its <code>hideNotify</code> method called. * Then this screen's <code>showNotify</code> method will be invoked followed * by the <code>paint</code> method. */ public void show () { // Set the wrapped canvas as the current screen. UIManager.setScreen( this, slave ); } /** * Checks if this screen is actually visible on the display. In * order for a screen to be visible, all of the following must be true: * the MIDlet must be running in the foreground, the screen must be the * current one, and the screen must not be obscured by a system screen. * * @return <code>true</code> if