[soofika]

Any idea why I am getting a null pointer exception from the following code

public class gCanvas extends GameCanvas implements Runnable {
....
....
public void run() {
while (true) {
Graphics g = getGraphics();
g.setColor(255,0,0);
g.fillRect(0, 0, 100, 100); // <-- this works
lm.paint(getGraphics(), 0, 0); // <-- exception error
flushGraphics();
try {
Thread.currentThread().sleep(10);
} catch (Exception e) {}
}
}

[jappit]

Hi soofika,

are you defining somewhere your 'lm' instance? From your code, it seems that it is still null when you call its paint() method.

Pit

[soofika]

Originally Posted by jappit

Hi soofika,

are you defining somewhere your 'lm' instance? From your code, it seems that it is still null when you call its paint() method.

Pit

I think I am Pit.. but here is more complete code snippet..

public class gCanvas extends GameCanvas implements Runnable {

public gCanvas() {
super(false);
}
private mGolf parent;
private LayerManager lm;
private TiledLayer tl;

public gCanvas(final mGolf parent) {
super(false);
this.parent = parent;
}

public void init() throws IOException{
Image bg = Image.createImage("/rsc/cop_ov.png");
tl = new TiledLayer(1,1,bg,512,512);
lm.append(tl);
lm.setViewWindow(0, 0, bg.getWidth(), bg.getHeight());
}

public void start() throws Exception {

// create and load Midlet
Thread runner = new Thread(this);
runner.start();

}

public void run() {
while (true) {
Graphics g = getGraphics();
g.setColor(255,0,0);
g.fillRect(0, 0, 100, 100);
lm.paint(getGraphics(), 0, 0);
flushGraphics();
try {
Thread.currentThread().sleep(10);
} catch (Exception e) {}
}

}

}

[jappit]

From your code it seems that your LayerManager instance is not initialized anywhere. A line like this should be present:

lm = new LayerManager();

Also, is your init() method called somewhere?

Pit

[soofika]

Originally Posted by jappit

From your code it seems that your LayerManager instance is not initialized anywhere. A line like this should be present:

lm = new LayerManager();

Also, is your init() method called somewhere?

Pit

That is a good catch Piit.. I added that as follows..but I am still getting the same error...

public void init() throws IOException{
lm = new LayerManager();
Image bg = Image.createImage("/rsc/cop_ov.png");
tl = new TiledLayer(1,1,bg,512,512);
lm.append(tl);
lm.insert(tl, 1);
lm.setViewWindow(0, 0, getWidth(), getHeight());
}

[jappit]

Hi soofika,

are you calling your init() method somewhere in your code (it's not called in the code you've posted)?

Pit