Is there a way to make a sound file loop without getting a null pointer error?
Gingervitis wrote ...
2013/6/9
Sound loops
Use the GreenfootSound class. Here is the API . You should use the playLoop() method.
I used that but i keep getting a null pointer error
public Man()
{
rain = new GreenfootSound("Rain.wav");
}
public void sound()
{
if (soundCount == 1)
{
rain.playLoop();
soundCount++;
}
}Your code looks fine from what I can see. I tried using this myself and it works fine, so it has to be somewhere else in your code the problem is.
This is my short code for using it.
public SoundWorld()
{
// Create a new world with 600x400 cells with a cell size of 1x1 pixels.
super(600, 400, 1);
GreenfootSound sound = new GreenfootSound("sound.mp3");
sound.playLoop();
}
Please show the entire class. It could be that 'soundCount' never becomes one or 'rain' is being set to something else before this code executes.
import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
/**
* Write a description of class Man here.
*
* @author (your name)
* @version (a version number or a date)
*/
public class Man extends Animal
{
private HealthBar health;
private HealthBar charge;
private GreenfootSound rain;
int count;
int hpAdd = 125;
int beamCount = 1;
int soundCount = 1;
/**
* Act - do whatever the Man wants to do. This method is called whenever
* the 'Act' or 'Run' button gets pressed in the environment.
*/
public void act()
{
moving();
ifCanSee();
beam();
sound();
end();
count++;
hpAdd++;
beamCount++;
}
public Man(HealthBar healthBar, HealthBar healthbar2)
{
health = healthBar;
charge = healthbar2;
}
public void moving()
{
if (Greenfoot.getMouseInfo() != null)
{
if( getX() <= Greenfoot.getMouseInfo().getX() )
{
move(-1);
}
}
if (Greenfoot.getMouseInfo() != null)
{
if ( getX() >= Greenfoot.getMouseInfo().getX() )
{
move(1);
}
}
}
public Man()
{
rain = new GreenfootSound("Rain.wav");
}
public void sound()
{
if (soundCount == 1)
{
Greenfoot.playSound("Rain.wav");
//rain.playLoop();
soundCount++;
}
}
public void ifCanSee()
{
Actor rd = getOneIntersectingObject(Raindrop.class);
if (rd != null) getWorld().removeObject(rd);
if (rd != null ) health.subtract(1);
if (rd != null) hpAdd = 100;
if (hpAdd >= 125)
{
health.add(1);
hpAdd = 90;
}
Actor lightning1 = getOneIntersectingObject(Lightning.class);
if (lightning1 != null) health.subtract(5);
if (lightning1 != null) getWorld().removeObject(lightning1);
Actor lightning2 = getOneIntersectingObject(Lightning2.class);
if (lightning2 != null) health.subtract(5);
if (lightning2 != null) getWorld().removeObject(lightning2);
}
public void end()
{
if (health.getValue() == 0)
{
Greenfoot.stop();
Label label = new Label("Game Over");
getWorld().addObject(label, 326, 229);
}
}
public void beam()
{
if (Greenfoot.isKeyDown("space") && beamCount >=1)
{
getWorld().addObject(new Beam(), Greenfoot.getMouseInfo().getX()-4, Greenfoot.getMouseInfo().getY()+28);
charge.subtract(2);
}
else
{
charge.add(1);
getWorld().removeObjects(getWorld().getObjects(Beam.class));
}
if (charge.getValue() == 0)
{
beamCount = -499;
}
if (health.getValue() <=50 && canSee(Beam.class) )
{
if (hpAdd >= 95)
{
health.add(1);
hpAdd = 90;
}
}
if (canSee(Beam.class) && canSee(Flower.class) && charge.getValue() <= 100)
{
charge.add(300);
health.setMaximumValue(health.getMaximumValue()+5);
eat(Flower.class);
}
}
}
If you create a Man object by using the constructor that takes the HealthBar objects, the field 'rain' is never set.
I see! The sound is never defined and therefore it is null. You have two contructors for the man.
public Man(HealthBar healthBar, HealthBar healthbar2)
{
health = healthBar;
charge = healthbar2;
}
and
public Man()
{
rain = new GreenfootSound("Rain.wav");
}
If you create a new man using the first contructor your sound is never created. Put this(); in the first contructor or move the sound code.
To secure that the program doesn't crash you can change sound() as well.
This makes sure that the sound is not null.
public void sound()
{
if (soundCount == 1 && rain != null)
{
rain.playLoop();
soundCount++;
}
}I think that did it! Thank you!
You need to login to post a reply.