/* * * Copyright ? 2007 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */package example.photoalbum;import example.About;import java.io.DataInputStream;import java.io.IOException;import java.util.Vector;import javax.microedition.io.Connector;import javax.microedition.io.ContentConnection;import javax.microedition.io.HttpConnection;import javax.microedition.lcdui.*;import javax.microedition.midlet.*;import javax.microedition.rms.*;/** * The PhotoAlbum MIDlet provides the commands and screens * that implement a simple photograph and animation album. * The images and animations to be displayed are configured * in the descriptor file with attributes. * <p> * Options are provided to to vary the speed of display * and the frame style. * */public class PhotoAlbum extends MIDlet implements CommandListener, ItemStateListener, Runnable {    /** The Command object for the About command */    private Command aboutCommand;    /** The Command object for the Exit command */    private Command exitCommand;    /** The Command object for the Ok command */    private Command okCommand;    /** The Command object for the Options command */    private Command optionsCommand;    /** The Command object for the Back command */    private Command backCommand;    /** The Command object for the Cancel command */    private Command cancelCommand;    /** The Form object for the Progress form */    private Form progressForm;    /** The Gauge object for the Progress gauge */    private Gauge progressGauge;    /** The Form object for the Options command */    private Form optionsForm;    /** Set of choices for the border styles */    private ChoiceGroup borderChoice;    /** Set of choices for the speeds */    private ChoiceGroup speedChoice;    /** The current display for this MIDlet */    private Display display;    /** The PhotoFrame that displays images */    private PhotoFrame frame;    /** The Alert for messages */    private Alert alert;    /** Contains Strings with the image names */    private Vector imageNames;    /** List of Image titles for user to select */    private List imageList;    /** Name of current image, may be null */    private String imageName;    /** Current thread loading images, may be null */    private Thread thread;    /** Name of persistent storage */    private final String optionsName = "PhotoAlbum";    /** Persistent storage for options */    private RecordStore optionsStore;    private boolean firstTime = true;    /**     * Construct a new PhotoAlbum MIDlet and initialize the base options     * and main PhotoFrame to be used when the MIDlet is started.     */    public PhotoAlbum() {        display = Display.getDisplay(this);        exitCommand = new Command("Exit", Command.EXIT, 1);        optionsCommand = new Command("Options", Command.SCREEN, 1);        okCommand = new Command("Ok", Command.OK, 3);        backCommand = new Command("Back", Command.BACK, 3);        cancelCommand = new Command("Cancel", Command.CANCEL, 1);        aboutCommand = new Command("About", Command.HELP, 30);        frame = new PhotoFrame();        frame.setStyle(2);        frame.setSpeed(2);        frame.addCommand(optionsCommand);        frame.addCommand(backCommand);        frame.setCommandListener(this);        alert = new Alert("Warning");        setupImageList();        firstTime = true;    }    /**     * Start up the Hello MIDlet by setting the PhotoFrame     * and loading the initial images.     */    protected void startApp() {        if (firstTime) {            if (imageList.size() > 0) {                display.setCurrent(imageList);                openOptions();                restoreOptions();            } else {                alert.setString("No images configured.");                display.setCurrent(alert, imageList);            }            firstTime = false;        }        openOptions();        restoreOptions();    }    /**     * Pause is used to release the memory used by Image.     * When restarted the images will be re-created.     * Save the options for the next restart.     */    protected void pauseApp() {        saveOptions();    }    /**     * Destroy must cleanup everything not handled by the garbage collector.     * In this case there is nothing to cleanup.     * Save the options for the next restart.     * @param unconditional true if this MIDlet should always cleanup     */    protected void destroyApp(boolean unconditional) {        saveOptions();        frame.reset(); // Discard images cached in the frame.        saveOptions();        closeOptions();    }    /**     * Respond to commands. Commands are added to each screen as     * they are created.  Each screen uses the PhotoAlbum MIDlet as the     * CommandListener. All commands are handled here:     * <UL>     * <LI>Select on Image List - display the progress form and start the thread     *  to read in the images.     * <LI>Options - display the options form.     * <LI>Ok on the Options form - returns to the PhotoFrame.     * <LI>Back - display the Image List, deactivating the PhotoFrame.     * <LI>Cancel - display the image List and stop the thread loading images.     * <LI>Exit - images are released and notification is given that the MIDlet     *  has exited.     * </UL>     * @param c the command that triggered this callback     * @param s the screen that contained the command     */    public void commandAction(Command c, Displayable s) {        if (c == exitCommand) {            // Cleanup and notify that the MIDlet has exited            destroyApp(false);            notifyDestroyed();        } else if (c == optionsCommand) {            // Display the options form            display.setCurrent(genOptions());        } else if ((c == okCommand) && (s == optionsForm)) {            // Return to the PhotoFrame, the option values have already            // been saved by the item state listener            display.setCurrent(frame);        } else if (c == List.SELECT_COMMAND) {            // Display the progress screen and            // start the thread to read the images            int i = imageList.getSelectedIndex();            imageName = (String)imageNames.elementAt(i);            display.setCurrent(genProgress(imageList.getString(i)));            thread = new Thread(this);            thread.start();        } else if (c == backCommand) {            // Display the list of images.            display.setCurrent(imageList);        } else if (c == cancelCommand) {            // Signal thread to stop and put an alert.            thread = null;            alert.setString("Loading images cancelled.");            display.setCurrent(alert, imageList);        } else if (c == aboutCommand) {            About.showAbout(display);        }    }    /**     * Listener for changes to options.     * The new values are set in the PhotoFrame.     * @param item - the item whose value has changed.     */    public void itemStateChanged(Item item) {        if (item == borderChoice) {            frame.setStyle(borderChoice.getSelectedIndex());        } else if (item == speedChoice) {            frame.setSpeed(speedChoice.getSelectedIndex());        }    }    /**     * Generate the options form with speed and style choices.     * Speed choices are stop, slow, medium, and fast.     * Style choices for borders are none, plain, fancy.     * @return the generated options Screen     */    private Screen genOptions() {        if (optionsForm == null) {            optionsForm = new Form("Options");            optionsForm.addCommand(okCommand);            optionsForm.setCommandListener(this);            optionsForm.setItemStateListener(this);            speedChoice = new ChoiceGroup("Speed", Choice.EXCLUSIVE);            speedChoice.append("Stop", null);            speedChoice.append("Slow", null);            speedChoice.append("Medium", null);            speedChoice.append("Fast", null);            speedChoice.append("Unlimited", null);            speedChoice.setSelectedIndex(frame.getSpeed(), true);            optionsForm.append(speedChoice);            borderChoice = new ChoiceGroup("Borders", Choice.EXCLUSIVE);            borderChoice.append("None", null);            borderChoice.append("Plain", null);            borderChoice.append("Fancy", null);            borderChoice.setSelectedIndex(frame.getStyle(), true);            optionsForm.append(borderChoice);        }        return optionsForm;    }    /**     * Generate the options form with image title and progress gauge.     * @param name the title of the Image to be loaded.     * @return the generated progress screen     */    private Screen genProgress(String name) {        if (progressForm == null) {            progressForm = new Form(name);            progressForm.addCommand(cancelCommand);            progressForm.setCommandListener(this);            progressGauge = new javax.microedition.lcdui.Gauge("Loading images...", false, 9, 0);            progressForm.append(progressGauge);        } else {            progressGauge.setValue(0);            progressForm.setTitle(name);        }        return progressForm;    }    /**     * Check the attributes in the descriptor that identify     * images and titles and initialize the lists of imageNames     * and imageList.     * <P>     * The attributes are named "PhotoTitle-n" and "PhotoImage-n".     * The value "n" must start at "1" and increment by 1.