Greenfoot

Spock47

2023/3/28

#

KCee wrote...

im not really sure what you mean by stacktrace but this is what it says:

What you posted is the stacktrace. Very good. For simplicity (since asking whether villager is grabbed is very common), please add the method to Villager:

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public boolean isGrabbed() {
    final VehicleWorld world = (VehicleWorld)getWorld();
    if (world == null) {
        return false;
    }
    return world.isGrabbed(this);
}

KCee wrote...

java.lang.ClassCastException: class GoodWitch cannot be cast to class Villager (GoodWitch and Villager are in unnamed module of loader java.net.URLClassLoader @786b6cc9) at PoisonCloud.act(PoisonCloud.java:29) at greenfoot.core.Simulation.actActor(Simulation.java:567) at greenfoot.core.Simulation.runOneLoop(Simulation.java:530) at greenfoot.core.Simulation.runContent(Simulation.java:193) at greenfoot.core.Simulation.run(Simulation.java:183)

Ok, the class cast exception is the problem mentioned at the end of thread https://greenfoot.org/topics/65329/0#post_148583 So, you have to decide: Option A: If PoisonCloud can poison any Pedestrian (including Witches), change PoisonCloud lines 29 through 33 to

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if (touched instanceof Villager && ((Villager)touched).isGrabbed()) {
    continue;
}

Option B: (code by danpost) If PoisonCloud can poison only villagers, change PoisonCloud lines 27 through 35 to:

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for (Object obj : getIntersectingObjects(Villager.class)) {
    Villager villager = (Villager)obj;
    if ( ! villager.isGrabbed()) {
        getWorld().removeObject(villager);
        break;
    }
}

Spock47

2023/3/28

#

KCee wrote...

After doing this when i try to call the method here:

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public void act()
    {
        if (timer == 0) 
        {
            drive();
        } 
        actionWithGrabbed();
    }

You don't have to call the method there, keep "checkHitPedestrian();" at this position. The actionWithGrabbed method will automatically be called by it.

Spock47

2023/3/28

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Ok, please let me know if there is any other problem. (Currently I assume that I added answers to all questions. :) )

KCee

2023/3/28

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another question regarding lane changes in the lanechange discussion post

danpost

2023/3/28

#

KCee wrote...

poison class code: << Code Omitted >>

All the cloud should do is dissapate and get removed:

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import greenfoot.*; 
 
public class PoisonCloud extends Actor
{
    private int trans = 250;
 
    public PoisonCloud ()
    {
        getImage().scale(image.getWidth()-150, image.getHeight()-120);
    }
      
    public void act()
    {
        getImage().setTransparency(--trans);
        if (trans < 5) getWorld().removeObject(this);
    }
}

Spock47

2023/3/28

#

KCee wrote...

another question regarding lane changes in the lanechange discussion post

I think @danpost is more qualified than me to answer the lane change question (he had already looked in detail into the lane change thread): https://greenfoot.org/topics/65331 (Only thing I can add at this moment: Is the changeLanes method called from somewhere, e.g from the act method?)

KCee

2023/3/28

#

I just wanna thank Spock and Danpost for helping me out these last few days youve been a great help and i wouldnt have been able to finish this project without you guys thanks!

Spock47

2023/3/28

#

You're welcome. I am glad to help. I hope you found some fun with programming and keep coding.

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Demon class killing villagers that are being grabbed