I used this topic as tutorial, but ended up getting a 'java.lang.NullPointerException' when trying to run, stemming from
'at Icebound_Camp01.updateTimerDisplay(Icebound_Camp01.java:93)'
'at Icebound_Camp01.<init>(Icebound_Camp01.java:13)'
I am fairly new to Greenfoot and coding in general, so sorry in advance.
Full Code:
import greenfoot.*;
public class Icebound_Camp01 extends World
{
//initiate privates
private Actor timerDisplay = new SimpleActor();
private int timeElapsed;
private int timeCounter;
public Icebound_Camp01()
{
//begin world and set speed
super(600, 400, 1);
Greenfoot.setSpeed(50);
//timer dislay
updateTimerDisplay();
addObject(timerDisplay, 80, 20);
//initiate coord and counter vairables
int x;
x=0;
int y;
y=0;
int a;
a=0;
//initiate location variables
int Width;
Width = (x);
int Height;
Height = (y);
//set perimeter
while (a <=13)
{
a=a+1;
addObject(new Wall(),Width,0);
Width = (Width+45);
}
while (a >=13 && a <=23)
{
a=a+1;
addObject(new Wall(),Width,Height);
Height = (Height+45);
}
while (a >=23 && a <=38)
{
a=a+1;
addObject(new Wall(),Width,Height);
Width = (Width-45);
}
while (a >=38 && a <=48)
{
a=a+1;
addObject(new Wall(),Width,Height);
Height = (Height-45);
}
//initate enemy spawn location and coutner variables
int EnemySpawnX;
int EnemySpawnY;
//spawn enemy
EnemySpawnX = Greenfoot.getRandomNumber(200)+50;
EnemySpawnY = Greenfoot.getRandomNumber(320)+40;
addObject(new Enemy(),EnemySpawnX,EnemySpawnY);
//initate enemy spawn location and coutner variables
int PlayerSpawnX;
int PlayerSpawnY;
//spawn player
PlayerSpawnX = Greenfoot.getRandomNumber(50)+500;
PlayerSpawnY = Greenfoot.getRandomNumber(320)+40;
addObject(new Player(),PlayerSpawnX,PlayerSpawnY);
//timer
timeCounter = (timeCounter+1)%55;
if (timeCounter == 0)
{
timeElapsed++;
updateTimerDisplay();
}
}
//timer dispay
private void updateTimerDisplay()
{
timerDisplay.setImage(new GreenfootImage("Time: "+timeElapsed, 24, null, null));
}
}
