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Thread: Problem with for each cicles

  1. #1
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    Default Problem with for each cicles

    Hi guys
    i have a problem, first i have two cicles for each to print a line like a cross to an object, thats actualize the line when the object moves, my problem is when i got two objects pointing to the same object, the cross line of the first targeting him, dont desapears from the map and i dont know why.

    sorry for my bad english
    Thanks
    Entertainer


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Problem with for each cicles

    Please post the code you are having problems with, post what it prints out and explain what is wrong with the printout.
    If you don't understand my answer, don't ignore it, ask a question.

  3. #3
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    Default Re: Problem with for each cicles

    bug.jpg

    for (SimpleImage tower : towers) {
    for (MovingImage x : invaders) {
    if (Math.abs(tower.getPosition().distance(x.getPositi on())) < RANGE) {

    SimpleShape s = new SimpleShape(
    new Line2D.Double(tower.getPosition().getX()
    + tower.getDimension().width / 2, tower
    .getPosition().getY()
    + tower.getDimension().height / 2, x
    .getPosition().getX()
    + x.getDimension().width / 2, x
    .getPosition().getY()
    + x.getDimension().height / 2), Color.blue, 50);

    shot = s;
    window.getDisplayer().add(s);



    }
    }
    }
    }

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: Problem with for each cicles

    How can the code by compiled and executed for testing? Can you make a small simple program that compiles, executes and shows the problem.

    Be sure to wrap your code with code tags:
    [code=java]
    <YOUR CODE HERE>
    [/code]
    to get highlighting and preserve formatting.
    If you don't understand my answer, don't ignore it, ask a question.

  5. The Following User Says Thank You to Norm For This Useful Post:

    Entertainer (March 26th, 2013)

  6. #5
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    Default Re: Problem with for each cicles

    if (shot != null) window.getDisplayer().remove(shot);  
            for (SimpleImage tower : towers) {  
            for (MovingImage x : invaders) {  
     
                    if (Math.abs(tower.getPosition().distance(x.getPosition())) < RANGE) {  
     
                        // if (shooting == true) { // to target one target at once   
     
     
                        System.out.println(shot);  
                        SimpleShape s = new SimpleShape(  
                                new Line2D.Double(tower.getPosition().getX()  
                                        + tower.getDimension().width / 2, tower  
                                        .getPosition().getY()  
                                        + tower.getDimension().height / 2, x  
                                        .getPosition().getX()  
                                        + x.getDimension().width / 2, x  
                                        .getPosition().getY()  
                                        + x.getDimension().height / 2),  
                                Color.green, 100);                  window.getDisplayer().refresh();  
                                        shot = s;  
     
                            window.getDisplayer().remove(shot);  
     
                                                    shooting = false;  
     
                        window.getDisplayer().add(s);  
     
                        }  
     
                    }  
                }
    My objective is target two objects at the same time( two or more towers pointing at objects if they are in range), i think the problem is when we change the tower s(variable) turns null but i dont know why...

    Image:bug.jpg

  7. #6
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    Default Re: Problem with for each cicles

    Can you make a small simple program that compiles, executes and shows the problem.

    Please edit the post and wrap your code with code tags:
    [code=java]
    <YOUR CODE HERE>
    [/code]
    to get highlighting and preserve formatting.

    when we change the tower s(variable) turns null
    Where does the null value come from?
    If you don't understand my answer, don't ignore it, ask a question.

  8. #7
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    Default Re: Problem with for each cicles

    i think when two objects tower change the value of variable s, my ideia is dont let second tower change s value but i dont know how can i do it ;/

  9. #8
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    Default Re: Problem with for each cicles

    dont let second tower change s value
    How do you know whether it is the first tower or the second tower? Can you use that information to stop second tower from making any changes.
    If you don't understand my answer, don't ignore it, ask a question.

  10. #9
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    Default Re: Problem with for each cicles

    thats is the problem i dont know which tower acess to variable s and i dont know how to restrict that ;/

  11. #10
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    Default Re: Problem with for each cicles

    Without a SSCCE there isn't much more I can do.
    If you don't understand my answer, don't ignore it, ask a question.

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