类型不匹配:无法从void转换为ArrayList <String>

Question

为什么我为此代码收到此错误？我有正确的ArrayList和Collections导入

private ArrayList<String> tips;

public TipsTask(ArrayList<String> tips){
    this.tips = Collections.shuffle(tips);
}

Answer 1

Collections.shuffle(tips);

Collections.shuffle返回void,你不能给一个void赋值ArrayList.

你可以这样做:

    Collections.shuffle(tips);
    this.tips = tips;