Discussions

<Code Omitted>this is the problem. getWorld returns null, and you can't use an object which is null so you get a null pointer exception. To fix it, I recommend moving this code to the addedToWorld method: <Code Omitted> For more about exceptions, check this out or this.

I'm not exactly sure that I'll properly help you but I thought you might be interested to use the Background Parallax Builder. Here's a blog post about it http://webdesy.com/wordpress-tutorials/parallax-scrolling-builder/ And a direct link to the tool http://web-features.net/ There's also a video about how exactly you can use that tool.

that could be an option. can you help me with the code? because i really have no idea where to start Thank you

What you're talking about is state, and that means variables. The ship can be in one of three main states: - normal (state 0) - animating (state 1) - animation finished (state 2) You could use an 'int' field variable to track which state (0, 1, or 2). Call it 'hitState' or something similar. <Code Omitted> State 1 also needs a counter to count how many cycles the animation has run for. <Code Omitted> When the ship gets hit by an asteroid, you check the hitState. If it is currently 0, you set it to 1, and set animationCounter to 0.

You just need to put what you wrote above in code: "if the variable "lives" from the class Robson is 0" (in the Robson class, after the value of lives decreases) if(lives == 0) "the scoreboard shall appear and should show the variable "points" also from the class Robson" addObject(new Scoreboard(points), getWorld().getWidth() / 2, getWorld().getHeight() / 2); Since the scoreboard needs the points value, we send it to the scoreboard when we create it and add it to the world. The only thing is, you need to make sure the scoreboard can except an integer value in one of its constructors.

When you write a program, you're talking to the computer (specifically, the compiler) - it doesn't think like you do. It does exactly what you tell it, no more, no less.

Oh thanks- I didn't see it. It works now :-)

To let the ball bounce off you could use this method:

I'm not an expert on this, however you could set a private variable to the amount of bars of health in your health bar, and after every hit in the hit method minus 1 from the health variable. Then, you'd make the health bar's image update for every number, e.g having the health variable being at 4 showing a full health bar, at 3, less, etc until 0 where you'd effectively complete a method for the actor's death. Possibly just a removeObject but maybe you want to go into more detail.

thanks

You are not showing any code, here. Therefore, we do not know what is going on (why you are having this problem). The code for the class with the constructor in question would probably be in order, here.

So are we creating a mouse object and setting that to Greenfoot.getMouseInfo();? That makes alot more sense than what I was doing :P

The 'win' method IS tied in through the 'play' method. The reason that ties are not showing up is because you are not incrementing 'clicks' until after the call to 'play'. Switch the order of the two lines and that should fix that. You still need to figure out a way to get the coordinates of where in the world the mouse is clicking. Please review the MouseInfo class documentation. If you continue to have problems, post your world act() method with your situation.

Thanks, funny that's how I (and I assume others) do these types of checks all of the time, I just for some reason didn't this time. Danpost, always the voice of reason.