java - Removing something from array but game crashes -

java - Removing something from array but game crashes -

i have , array create few swords on tiled map , when step on them need deleted when step on them game chrashes.

at java.util.arraylist$itr.checkforcomodification(unknown source) @ java.util.arraylist$itr.next(unknown source)

my code:

i guess loop looking object if deleted?

private list<sword> swords = new arraylist<sword>();

i create them 1 time:

public gamerender(gameworld world, int gameheight) { (int = 0; i<100 ; i++ ) { swords.add(new sword()); }

when step on it:

for (sword sword : swords) { if(playery+7>=sword.position.y && playery+7<=sword.position.y+tilesize && playerx+7>=sword.position.x &&playerx+7<=sword.position.x+tilesize) { sword.pickme(); swords.remove(sword); } }

there other loop in render():

for (sword sword : swords) { sword.createme(); }

i dont think need see sword class. if i'll set in here. how prepare dont error?

for (sword sword : swords) { if(playery+7>=sword.position.y && playery+7<=sword.position.y+tilesize && playerx+7>=sword.position.x &&playerx+7<=sword.position.x+tilesize) { sword.pickme(); swords.remove(sword); //this line throws concurrentmodificationexception } }

due how enhanced for loop works, either need utilize iterator<sword> remove it:

iterator<sword> iterator = swords.iterator(); while(iterator.hasnext()) { sword sword = iterator.next(); if(playery+7>=sword.position.y && playery+7<=sword.position.y+tilesize && playerx+7>=sword.position.x &&playerx+7<=sword.position.x+tilesize) { sword.pickme(); iterator.remove(); } }

or following:

(int = 0; < swords.size(); i++) { sword sword = swords.get(i); if(playery+7>=sword.position.y && playery+7<=sword.position.y+tilesize && playerx+7>=sword.position.x &&playerx+7<=sword.position.x+tilesize) { sword.pickme(); swords.remove(i--); } }

java arrays libgdx