Yes,貌似添加了好多的代码啊 ;] ,在你添加更多代码时,你可能注意到一些Xcode中的一些警告.首先你先忽略这些警告,我们先添加少量最终缺失的部分,然后再来解释上面代码做了什么!
在Enemy.m中修改如下:
// Add the following at the beginning of initWithTheGame: (within the "if" condition) attackedBy = [[NSMutableArray alloc] initWithCapacity:5]; // Replace the contents of getRemoved method with the following: -(void)getRemoved
{ for(Tower * attacker in attackedBy)
{
[attacker targetKilled];
}
[self.parent removeChild:self cleanup:YES];
[theGame.enemies removeObject:self]; //Notify the game that we killed an enemy so we can check if we can send another wave [theGame enemyGotKilled];
} // Add the following methods -(void)getAttacked:(Tower *)attacker
{
[attackedBy addObject:attacker];
}
-(void)gotLostSight:(Tower *)attacker
{
[attackedBy removeObject:attacker];
}
-(void)getDamaged:(int)damage
{
currentHp -=damage; if(currentHp <=0)
{
[self getRemoved];
}
}
代码中最重要的部分是Tower中的update方法.炮塔将定时检查是否敌人进入了攻击范围,如果是,我们的炮塔将旋转然后开始向敌人开火.
一旦一个敌人被标记为被攻击,一个方法将被调度执行用之前初始的攻击频率去发射子弹.轮流的,每个敌人保持攻击自身炮塔的一个列表,所以当该敌人被摧毁时那些炮塔可以得到信号去停止攻击.
