从不同的班级

Question

我想从另一个不是活动的类更新TextView，但应用程序一直在粉碎.. 我希望你能帮忙

这是我想在了解游戏结果后更新文字的课程

  public class GameLogic {
    ...
    public void gameResult() {
            OnePlayerGameActivity gameActivity = new OnePlayerGameActivity();
            TextView result = (TextView) gameActivity.findViewById(R.id.game_result_textView);

            getPlayerChoice();

            int computer = computerChoice();

            if (mPlayerChoice == computer) {
                mPlayerStat += 0;
                mOpponentChoice += 0;
            } else if (mPlayerChoice == 1) { //ROCK
                switch (computer) {
                    case 1: //ROCK

                        break;
                    case 2:  //PAPER
                        mOpponentStat ++;
                        result.setText("LOST");
                        break;
    ...

所有代码都可以在GitHub

上找到

Answer 1

您正在创建活动的虚拟实例，该实例与内存中的实例无关，而是使用

传递活动实例

// in your OnePlayerGameActivity.java
// inside some method
GameLogic obj = new GameLogic (); // instance of GameLogic for demo
obj.gameResult(OnePlayerGameActivity.this); // pass instance

并将方法签名更改为

 public void gameResult(OnePlayerGameActivity gameActivity ) {
            TextView result = (TextView) gameActivity.findViewById(R.id.game_result_textView);