I've been pondering a solution for quite some time now. Every time I attempt to remove items from an ArrayList, I always end up with an Exception error. items.add() in relation to the ArrayList works perfectly fine, though I can't get my head around as to why it throws an exception when removing items (items.remove()).
This ArrayList is for an inventory, which draws and updates each item. I used the typical for loop to iterate through each object:
for (int i = 0; i < items.size(); i++)
Here's the inside of my Inventory class:
public class Inventory {
public static boolean bOpen;
public static boolean bSelected;
private Rectangle selectBox;
private Color hover;
private Color select;
private Color color;
private Font f;
private FontMetrics fontMetrics;
public static int tileCount;
private boolean pressed;
private int sx;
private int sy;
public boolean I;
private BufferedImage HUD;
private BufferedImage infoBase;
public static ArrayList<Item> items;
private int itemCount;
// Items
public static Shovel shovel;
public static PickAxe pickAxe;
public static Key key;
public Inventory() {
try {
HUD = ImageIO.read(getClass().getResource("/HUD.png"));
infoBase = ImageIO.read(getClass().getResource("/InfoBase.png"));
} catch (Exception e) {
e.printStackTrace();
}
items = new ArrayList<Item>();
// Init items
shovel = new Shovel();
pickAxe = new PickAxe();
key = new Key();
items.add(shovel);
items.add(pickAxe);
hover = new Color(150, 150, 180, 180);
select = new Color(255, 174, 0, 180);
f = new Font("Bodoni MT", Font.PLAIN, 12);
sx = 34;
sy = 198;
}
public void draw(Graphics2D g) {
itemCount = items.size();
if (I) {
bOpen = true;
}
if (bOpen) {
g.setColor(new Color(0, 0, 0, 180));
g.fillRect(0, 0, GamePanel.WIDTH, GamePanel.HEIGHT);
g.drawImage(HUD, 26, 194, 270, 41, null);
for (int i = 0; i < items.size(); i++) {
if (items.get(i) != null) {
items.get(i).update();
items.get(i).draw(g, 22 + i * 32, 180);
}
g.setColor(color);
g.setStroke(new BasicStroke(2));
selectBox = new Rectangle(sx, sy, 32, 32);
if (!bSelected && items.get(i) != null) {
color = hover;
items.get(tileCount).bSelected = false;
} else {
color = select;
if (items.get(i) != null) {
items.get(tileCount).bSelected = true;
g.drawImage(infoBase, 20, 59, null);
g.setFont(f);
fontMetrics = g.getFontMetrics();
int width = fontMetrics.stringWidth(items
.get(tileCount).getInfo());
g.drawString(items.get(tileCount).getInfo(),
GamePanel.WIDTH / 4 - width / 2, 80);
}
}
g.draw(selectBox);
}
if (GamePanel.right) {
bSelected = false;
if (GamePanel.left == false) {
if (!pressed) {
pressed = true;
if (tileCount <= itemCount - 2) {
try {
Thread.sleep(120);
sx = sx + 32;
tileCount = tileCount + 1;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
if (GamePanel.left) {
bSelected = false;
if (GamePanel.right == false) {
if (!pressed) {
pressed = true;
if (tileCount > 0) {
try {
Thread.sleep(120);
sx = sx + -32;
tileCount = tileCount - 1;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
if (GamePanel.right || GamePanel.left) {
pressed = false;
}
if (GamePanel.enter && itemCount > 0) {
bSelected = true;
}
}
if (itemCount > 8) {
items.remove(8);
}
System.out.println(items.size());
}
}
Here's the class where I call the items.remove() method:
public class Chest extends Item {
public static boolean bOpen;
private StringEvent se;
public Chest() {
se = new StringEvent();
bSolid = true;
}
public void draw(Graphics2D g, int x, int y) {
setRadius(TileLayer.xx + x + getWidth() / 2, TileLayer.yy + y
+ getHeight() / 2, 32, 32);
checkCollision();
if (bTouched) {
if (GamePanel.e) {
if (Inventory.key.bSelected == true) {
bOpen = true;
Inventory.key.bUsed = true;
} else
se.draw(g, this, 2, "Chest is locked.");
}
}
if (!bOpen) {
g.drawImage(content.chestShut(), TileLayer.xx + x,
TileLayer.yy + y, null);
}
if (bOpen) {
g.drawImage(content.chestOpen(), TileLayer.xx + x,
TileLayer.yy + y, null);
if (Inventory.bOpen == false) {
Audio.playOnce(Audio.unlock);
}
}
if (Inventory.key.bUsed && !bRemove) {
Inventory.items.remove(Inventory.key);
bRemove = true;
}
}
public void update() {
}
}
Any ideas on how to overcome this problem?
Edit: Here's the stacktrace:
Game (31) [Java Application]
Main.Game at localhost:49264
Thread [AWT-Shutdown] (Running)
Daemon Thread [AWT-Windows] (Running)
Thread [AWT-EventQueue-0] (Running)
Thread [Thread-2] (Suspended (exception IndexOutOfBoundsException))
ArrayList<E>.rangeCheck(int) line: not available
ArrayList<E>.get(int) line: not available
Inventory.draw(Graphics2D) line: 102
GamePanel.draw() line: 184
GamePanel.run() line: 105
Thread.run() line: not available
Thread [DestroyJavaVM] (Running)
Daemon Thread [Java Sound Event Dispatcher] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
Daemon Thread [Direct Clip] (Running)
C:\Program Files\Java\jre7\bin\javaw.exe (18 Sep 2014 18:40:22)
Thanks for the help so far.
I also get this in my console:
Exception in thread "Thread-2"
I tried editing the itemSize to items.size(), but unfortunately an error still occurs. I do not believe that the itemCount is the problem because the items.size() does not exceed the value of '8'.
EDIT: Ok, so I figured out the problem. items.get(i) is causing the Exception becuase of this:
if (!bSelected) {
color = hover;
if (items.get(i) != null) {
items.get(tileCount).bSelected = false;
} else {
color = select;
if (items.get(i) != null) {
items.get(tileCount).bSelected = true;
g.drawImage(infoBase, 20, 59, null);
g.setFont(f);
fontMetrics = g.getFontMetrics();
int width = fontMetrics.stringWidth(items
.get(tileCount).getInfo());
g.drawString(items.get(tileCount).getInfo(),
GamePanel.WIDTH / 4 - width / 2, 80);
}
}
It's because as SOON as the inventory opens, it tries to set items.get(i).bSelected = true or items.get(i).bSelected = false. Maybe it's trying to find something that doesn't exist in the ArrayList anymore? Still having the same error :/
[FIXED]
I had
if (items.get(i) != null) {
items.get(tileCount).bSelected = false;
}
when the item that's being removed doesn't even exist! I just deleted this statement and it works perfectly fine!