如何让两个物体在Farseer中碰撞并将冲动传递到第二个物体？(How to let two bodies collide in Farseer and pass the impulse to the 2nd body?)

 for..each构造迭代集合或数组中的每个元素。 构造的形式如下： 
 
for(Type varName : [Array || Collection]){
  //for each iteration varName is assigned an element in the collection/array
}
 
 在您的示例中，外部循环已正确构造，并将ArrayList分配给每次迭代的priority变量。 由于您希望迭代ArrayList优先级中的每个元素，因此内部循环未正确构造，但代码尝试使用priority ArrayList的元素。 下面的代码显示了正确的结构，并将ArrayList替换为List接口，这比使用集合的具体类型更受欢迎。 
 
public static void renderSprites(List<List<AbstractSprite>> priorities){
    for (List<AbstractSprite> priority : priorities){
        for(AbstractSprite sprite : priority)){
           renderSprite(sprite);
        }
    }
}

The for..each construct iterates over every element in a collection or an array. The construct is in the form:
 
for(Type varName : [Array || Collection]){
  //for each iteration varName is assigned an element in the collection/array
}
 
In your example the outer loop is properly constructed and will assign the ArrayList to the priority variable for each iteration. The inner loop is not properly constructed since you want to iterate over each element in the ArrayList priority, however the code attempts to use an element from the priority ArrayList. The following code shows the proper structure and replaces the ArrayList with the List interface, which is preferred over using the concrete type of the collection.
 
public static void renderSprites(List<List<AbstractSprite>> priorities){
    for (List<AbstractSprite> priority : priorities){
        for(AbstractSprite sprite : priority)){
           renderSprite(sprite);
        }
    }
}