Applet to Application

Newbie & Debugging Questions
#1

Hello, so after about a month of work I have created my first Java game on my own. It is a 2D turn based strategy, don’t laugh too hard when you see it. Right now though it is run through an applet, but I wish to move it to a application before I continue with development.

It’s a lot of code so I’ve posted the source below if you care to take a look at it. I’m essentially looking to have the bottom 1/4 of the screen with all the info be static, while you could scroll around the actual game window. I know this might seem quite ambiguous, but if you run the applet I think you’ll get what I’m saying. Also, willing to post pictures if needed.

Thanks!

#2

You can create an instance of the class that extends Applet and add it to a JFrame. However, the init(), start(), stop(), and destroy() methods are not called so you will have to manually call them after you add it :slight_smile:


JFrame frame = new JFrame("My Game");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(WIDTH,HEIGHT);

final MyApplet applet = new MyApplet();
frame.add(applet);

frame.setVisible(true);

applet.init();
applet.start();

frame.addWindowListener(new WindowAdapter() {
    public void windowClosing(WindowEvent we) {
        applet.stop();
        applet.destroy();
    }
});

Note: if you only use init(), then you don’t need to call the rest :slight_smile:

#3

Ok did that, but I seem to be getting null pointer errors from a method that declares all my images and audio files:


public void declareImages() {
		tr = new MediaTracker(this);
		
		tank_fire = getAudioClip(getCodeBase(), "tank_fire.wav");
		tank_destroyed = getAudioClip(getCodeBase(), "tank_destroyed.wav");
		
		plains1 = getImage(getCodeBase(), "plains.png");
		tr.addImage(plains1, 0);
		tiles[0] = plains1;

                //similar code below
}

EDIT: first of many errors


Exception in thread "main" java.lang.NullPointerException
	at java.applet.Applet.getCodeBase(Unknown Source)
	at com.rolledback.game.Main.declareImages(Main.java:103)
	at com.rolledback.game.Main.init(Main.java:62)
	at com.rolledback.game.Frame.main(Frame.java:20)
#4

Ah yes getCodeBase() won’t work. Use System.getProperty(“user.dir”) instead. :slight_smile:

#5

???

plains1 = getImage(System.getProperty("user.dir"), "plains.png");

The method getImage(URL, String) in the type Applet is not applicable for the arguments (String, String)

PS: thank you for such patience

#6

Ah, then just do this: getImage(.class.getResource(“plains.png”));

getResource returns a URL and searches for the file relative to the class.

#7

Bleh, also does not work, it may have to do with how I’ve organized my images.

plains1 = getImage(Main.class.getResource("plains.png"));

http://gyazo.com/ed98477ac89861ff82e6c7cbef98e49a

#8

Just put them in packages in your src folder, like this or something like this:


src
|--> code packages
|--> images
     |--> tiles
     |--> sprites
|--> sounds
#9

Did not solve the issue…could you maybe show me what you want with a screenshot, just in case I did not do what you meant?

:emo:

#10

Well it is best to use javax.imageio.ImageIO instead of createImage, but either way, you’ll need to do:


BufferedImage image = ImageIO.read(Main.class.getClassLoader().getResource("tiles/plains.png"));

Class.getClassLoader().getResource(…) returns a URL relative to the root of your project.

EDIT: It looks like you’ve added “tiles”, “original_models”, “team1_models”, “team2_modes” as source folders. Don’t do that, change them to normal folders under “src”.

#11

This is how I do it. All of the code is in “zman.example” and it’s sub directories, and all the resources go in “resources” and it’s sub directories. I just have eclipse treat them as packages in the src folder.

http://i1220.photobucket.com/albums/dd457/ZMan/example.png

#12

I LOVE YOU GUYS!

It took a bit of messing around, but the end result was this declaration:

plains1 = ImageIO.read(Main.class.getClassLoader().getResource("plains.png"));

I guess I didn’t have to reference the folder the image was in. Applet runs great. Now I just need to separate the 2 parts of the game screen.

#13

That looks neat.

Did it take you long?

#14

The project was started about a month and 2 weeks ago. All the artwork you see is original. I’m a senior in high school, so I’m pretty impressed on what I’ve been able to do with only 2 years of formal CS/Java and about a year of self taught under my belt. There is no animation though. I’ll see if I can export it to an .exe and I’ll put it on mediafire.

#15

Here’s the jar file for anyone who wants to play around with this, comments and suggestions are appreciated. :slight_smile:

Bleh, having bugs with the sounds. I’ll eventually reexport it. Too lazy though. So any ideas on how I could go about separating the dashboard looking thing from the map? I want to be able to have unlimited map sizes.

#16

Where’s the JAR? :wink:

#17

Just a quick question! Are those trees in the water?

#18

Ok fine, I’ll reupload it. The sounds have been removed since I can’t figure out how to declare them in a way that won’t give me errors and exceptions. I’ll figure that out tomorrow. ;D

http://www.mediafire.com/?97kb0wayagm00rq

No they are islands. MS Paint is only so amazing.

#19

Oh, I was talking about the image that you posted earlier. It looks like you’re painting your water (With a slight transparency) on top of various other ground types (Plains, Plains with big, fluffy trees, Plains with conifers.)

#20

Oh no. That is showing you where you can move your unit. And since this thread is starting to move onto the general development of this game, I feel like I should start a new more permanent thread. What forum should I put it in?