How to implement more than one Images in form and new Date instances

Question

In the CalendarCanvas class, the idea is to press on any day in the Calendar and a form will be presented with the actual date of the day THE USER picked (not just today's date as it's doing now) and underneath the form will be the image pertaining to the form (eg. June 21st (image.jpg)).

I'm having two problems.

Number one, the program only likes one image which is the Men.img. It will display that image in all of the three forms. The other two images will not display at all.

And I don't understand because I first started with one form and the images.jpg image and that image worked. All I did was create 2 new forms and switch the order of images.

I even reduced the sizes (width/height & KB) to match with Men.jpg but it still doesn't show. The string inside the ImageItem constructor doesn't even show.

Lastly how do I create a new instance of the calendar.getSelectedDate().toString() method to show the new user picked date so I can put that above the image when the user picks a different day?

In the keyPressed method, the commented out new instance of Alert will do that for me but I don't want an alert, I want it to be the title of the forms pertaining to what day the user picked.

Below is my code:

Class CalendarMidlet:

import java.io.IOException;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

/**
 * @author addylesson
 */
public class CalendarMidlet extends MIDlet {
    private Display mydisplay;
    private Command f;
    private Displayable d;

    public CalendarMidlet(){}

    public void startApp() {
        d = new CalendarCanvas(this);

        f = new Command("Exit", Command.EXIT, 0);
        d.addCommand(f);
        d.setCommandListener(new CommandListener()
        {
            public void commandAction(Command c, Displayable s)
            {

                if(c == f)

            notifyDestroyed();
            }
        } );

        mydisplay = Display.getDisplay(this);
        mydisplay.setCurrent(d);

    }




    public void startOver() {

        final Displayable d = new CalendarCanvas(this);

        d.addCommand(f);

        d.setCommandListener(new CommandListener()
        {
            public void commandAction(Command c, Displayable s)
            {

                if(c == f)

            notifyDestroyed();
            }
        } );
        mydisplay.setCurrent(d);
    }

    public void pauseApp() {
    }

    public void destroyApp(boolean unconditional) {
    }

}

Class CalendarCanvas:

import java.io.IOException;
import java.util.Date;

import javax.microedition.lcdui.*;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

public class CalendarCanvas extends Canvas
{
    CalendarWidget calendar = null;
    CalendarMidlet midlet = null;
        private Alert alert;
        private List mList;
        private Command f,e,n;
        private Display mydisplay;
        private Form form;
        private Form form2;
        private Form form3;
        private ImageItem imageItem;
        private ImageItem imageItem2;
        private ImageItem imageItem3;



    public CalendarCanvas(final CalendarMidlet m)
    {
        String day = calendar.getSelectedDate().toString();

                this.midlet = m;

        calendar = new CalendarWidget(new Date());

        calendar.headerFont = Font.getFont(Font.FACE_PROPORTIONAL, Font.STYLE_BOLD, Font.SIZE_LARGE);
        calendar.weekdayFont = Font.getFont(Font.FACE_PROPORTIONAL, Font.STYLE_BOLD, Font.SIZE_MEDIUM);
        calendar.weekdayBgColor = 0xccccff;
        calendar.weekdayColor = 0x0000ff;
        calendar.headerColor = 0xffffff;

                form = new Form(day);
                form2 = new Form("New Page");
                form3 = new Form("New Page");

                try 
                {
                    imageItem = new ImageItem(
                        "Men In Black 3: ",
                        Image.createImage("Men.jpg"),
                        ImageItem.LAYOUT_DEFAULT,
                        "DuKe");
                    form.append(imageItem);
                } catch(Exception s) {}

                try 
                {
                    imageItem2 = new ImageItem(
                        "Jordon vs Knicks: ",
                        Image.createImage("images.jpg"),
                        ImageItem.LAYOUT_DEFAULT,
                        "Not");
                    form2.append(imageItem2);
                } catch(Exception s) {}
                try 
                {
                    imageItem3 = new ImageItem(
                        "Horoscope: ",
                        Image.createImage("Men.jpg"),
                        ImageItem.LAYOUT_DEFAULT,
                        "DuKe");
                    form3.append(imageItem3);
                } catch(Exception s) {}

                alert = new Alert("Listen", "On this day "
                        +calendar.getSelectedDate().toString()+ "stuff happened", null, null);
                alert.setTimeout(Alert.FOREVER);


                n = new Command("Next", Command.SCREEN,0);
                f = new Command("Back", Command.BACK, 0);
                e = new Command("Exit", Command.EXIT, 1);
                form.addCommand(f);             
                form.addCommand(n);
                form2.addCommand(f);
                form2.addCommand(n);
                form3.addCommand(f);
                form3.addCommand(e);



                form.setCommandListener(new CommandListener()
                      {
                      public void commandAction(Command c, Displayable s)
                        {
                            if (c == f)

                            m.startOver();

                            if (c == e)
                                 m.notifyDestroyed();

                            if (c == n)
                                 Display.getDisplay(midlet).setCurrent(form2);
                        }
                      } );
                form2.setCommandListener(new CommandListener()
                      {
                      public void commandAction(Command c, Displayable s)
                        {
                            if (c == f)

                            m.startOver();

                            if (c == e)
                                 m.notifyDestroyed();

                            if (c == n)
                                 Display.getDisplay(midlet).setCurrent(form3);
                        }
                      } );
                form3.setCommandListener(new CommandListener()
                      {
                      public void commandAction(Command c, Displayable s)
                        {
                            if (c == f)

                            m.startOver();

                            if (c == e)
                                m.notifyDestroyed();
                        }
                      } );


        calendar.initialize();
    }


    protected void keyPressed(int key)
    {
        int keyCode = getGameAction(key);
        String day = calendar.getSelectedDate().toString();
        if(keyCode == FIRE)
        {
             /*Display.getDisplay(midlet).setCurrent(
                new Alert("Selected date", 
                                day, null, 
                                AlertType.CONFIRMATION)
            );*/
                       Display.getDisplay(midlet).setCurrent(form);
        }
        else
        {
            calendar.keyPressed(keyCode);

            repaint();
        }
    }

    protected void paint(Graphics g)
    {
        g.setColor(0xff0000);
        g.fillRect(0, 0, getWidth(), getHeight());

        calendar.paint(g);
    }

}

Class CalendarWidget:

import java.util.Calendar;
import java.util.Date;

import javax.microedition.lcdui.*;

public class CalendarWidget
{
    static final String[] MONTH_LABELS = new String[]{
        "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"
    };
    static final String[] WEEKDAY_LABELS = new String[]{
        "M", "T", "W", "T", "F", "S", "S"
    };
    /* starting week day: 0 for monday, 6 for sunday */
    public int startWeekday = 0;

    /* elements padding */
    public int padding = 2;

    /* cells border properties */
    public int borderWidth = 4;
    public int borderColor = 0x000000;

    /* weekday labels properties */
    public Font weekdayFont = Font.getDefaultFont();
    public int weekdayBgColor = 0xcccccc;
    public int weekdayColor = 0xffffff;

    /* header (month-year label) properties */
    public Font headerFont = Font.getDefaultFont();
    public int headerBgColor = 0xff0000;
    public int headerColor = 0xff0000;

    /* cells properties */
    public Font font = Font.getDefaultFont();
    public int foreColor = 0xffffff;
    public int bgColor = 0xcccccc;
    public int selectedBgColor = 0x000000;
    public int selectedForeColor = 0xff0000;

    /* internal properties */
    int width = 0;
    int height = 0;
    int headerHeight = 0;
    int weekHeight = 0;
    int cellWidth = 0;
    int cellHeight = 0;

    /* internal time properties */
    long currentTimestamp = 0;
    Calendar calendar = null;
    int weeks = 0;

public CalendarWidget(Date date)
{
    calendar = Calendar.getInstance();

    //we'll see these 2 methods later
    setDate(date);

    initialize();
}
public Date getSelectedDate()
{
    return calendar.getTime();
}
public void setDate(Date d)
{
    currentTimestamp = d.getTime();

    calendar.setTime(d);

    //weeks number can change, depending on week starting day and month total days
    this.weeks = (int)Math.ceil(((double)getStartWeekday() + getMonthDays()) / 7);
}
public void setDate(long timestamp)
{
    setDate(new Date(timestamp));
}
void initialize()
{
    //let's initialize calendar size
    this.cellWidth = font.stringWidth("MM") + 3 * padding;
    this.cellHeight = font.getHeight() + 15 * padding;

    this.headerHeight = headerFont.getHeight() + 2 * padding;
    this.weekHeight = weekdayFont.getHeight() + 2 * padding;

    this.width = 7 * (cellWidth + borderWidth) + borderWidth;
    initHeight();
}
void initHeight()
{
    this.height = 
        headerHeight + weekHeight + 
        this.weeks * (cellHeight + borderWidth) + borderWidth;
}
int getMonthDays()
{
    int month = calendar.get(Calendar.MONTH);

    switch(month)
    {
    case 3:
    case 5:
    case 8:
    case 10:
        return 30;
    case 1:
        return calendar.get(Calendar.YEAR) % 4 == 0 && calendar.get(Calendar.YEAR) % 100 != 0 ? 29 : 28;
    default:
        return 31;
    }
}
int getStartWeekday()
{
    //let's create a new calendar with same month and year, but with day 1
    Calendar c = Calendar.getInstance();

    c.set(Calendar.MONTH, calendar.get(Calendar.MONTH));
    c.set(Calendar.YEAR, calendar.get(Calendar.YEAR));
    c.set(Calendar.DAY_OF_MONTH, 1);

    //we must normalize DAY_OF_WEEK returned value
    return (c.get(Calendar.DAY_OF_WEEK) + 5) % 7;
}
public void keyPressed(int key)
{
    switch(key)
    {
    case Canvas.UP:
        go(-7);
        break;
    case Canvas.DOWN:
        go(7);
        break;
    case Canvas.RIGHT:
        go(1);
        break;
    case Canvas.LEFT:
        go(-1);
        break;
    }
}
void go(int delta)
{
    int prevMonth = calendar.get(Calendar.MONTH);

    setDate(currentTimestamp + 86400000 * delta);

    //we have to check if month has changed
    //if yes, we have to recalculate month height
    //since weeks number could be changed
    if(calendar.get(Calendar.MONTH) != prevMonth)
    {
        initHeight();
    }
}
public void paint(Graphics g)
{
    //painting background
    g.setColor(bgColor);
    g.fillRect(0, 0, width, height);

    //painting header (month-year label)
    g.setFont(headerFont);
    g.setColor(headerColor);
    g.drawString(MONTH_LABELS[calendar.get(Calendar.MONTH)] + " " + calendar.get(Calendar.YEAR), width / 2, padding, Graphics.TOP | Graphics.HCENTER);

    //painting week days labels
    g.translate(0, headerHeight);

    g.setColor(weekdayBgColor);
    g.fillRect(0, 0, width, weekHeight);

    g.setColor(weekdayColor);
    g.setFont(weekdayFont);

    for(int i = 0; i < 7; i++)
    {
        g.drawString(WEEKDAY_LABELS[(i + startWeekday) % 7],
            borderWidth + i * (cellWidth + borderWidth) + cellWidth / 2,
            padding,
            Graphics.TOP | Graphics.HCENTER
        );
    }


    g.translate(0, weekHeight);

    g.setColor(borderColor);

    for(int i = 0; i <= weeks; i++)
    {
        g.fillRect(0, i * (cellHeight + borderWidth), width, borderWidth);
    }
    for(int i = 0; i <= 7; i++)
    {
        g.fillRect(i * (cellWidth + borderWidth), 0, borderWidth, height - headerHeight - weekHeight);
    }


    int days = getMonthDays();
    int dayIndex = (getStartWeekday() - this.startWeekday + 7) % 7;

    g.setColor(foreColor);

    int currentDay = calendar.get(Calendar.DAY_OF_MONTH);

    for(int i = 0; i < days; i++)
    {
        int weekday = (dayIndex + i) % 7;
        int row = (dayIndex + i) / 7;

        int x = borderWidth + weekday * (cellWidth + borderWidth) + cellWidth / 2;
        int y = borderWidth + row * (cellHeight + borderWidth) + padding;


        if(i + 1 == currentDay)
        {
            g.setColor(selectedBgColor);
            g.fillRect(
                borderWidth + weekday * (cellWidth + borderWidth), 
                borderWidth + row * (cellHeight + borderWidth), 
                cellWidth, cellHeight);
            g.setColor(selectedForeColor);
        }

        g.drawString("" + (i + 1), x, y, Graphics.TOP | Graphics.HCENTER);


        if(i + 1 == currentDay)
        {
            g.setColor(foreColor);
        }
    }

    g.translate(0, - headerHeight - weekHeight);
}
}

Answer 1

There are no evident mistakes in the code snippet you posted.

To easier find out what could possibly go wrong when your MIDlet becomes complicated like that, add logging statements and run it in emulator watching console output.

You definitely need to add logging within catch blocks. To find out why I am making such a strong statement, search Web for something like Java swallow exceptions.

Other points where I'd recommend logging are within commandAction and when invoking setCurrent. When developing, feel free to add more where you feel the need to (keyPressed looks like a good candidate for that, too).

public class Log {
    // utility class to keep logging code in one place
    public static void log (String message) {
        System.out.println(message);
        // when debugging at real device, S.o.p above can be refactored
        //  - based on ideas like one used here (with Form.append):
        //    http://stackoverflow.com/questions/10649974
        //  - Another option would be to write log to RMS
        //    and use dedicated MIDlet to read it from there
        //  - If MIDlet has network connection, an option is
        //    to pass log messages over the network. Etc etc...
    }
}


// ... other classes...
    // ...
    catch (Exception e) {
        Log.log("unexpected exception: [" + e + "]");
    }

    // ...
    public void commandAction(Command c, Displayable s) {
        Log.log("command: [" + c.getCommandLabel()
                + "] at screen: [" + d.getTitle() + "]");
        // ...
    }

    // ...
    Log.log("set current: [" + someDisplayable.getTitle() + "]");
    mydisplay.setCurrent(someDisplayable);
    // ...

    protected void keyPressed(int key) {
        Log.log("key pressed: [" + getKeyName(key) + "]");
        // ...
    }