java - 如何从另一个 Activity 发送/检测对特定 Activity 的引用/标记

Question

如果特定的Activity是从另一个Activity启动的，我如何发送或检测引用或标志？我实际上需要一种形式，其中只有当特定代码被特定 Activity 调用时，我才能执行该代码，例如:

Activity 1:

Intent intent = new Intent(this,ranking.class);
startActivity(intent);

Activity 2:

Intent intent = new Intent(this,ranking.class);
startActivity(intent);

Ranking.class(这是伪代码，因为我真的不知道该怎么做/做什么):

if(I was called by Activity  1) {
    //do something
} else {
     finish();
}

Answer 1

您可以向您的Intent.putExtra一条消息。

Activity 1

Intent intent = new Intent(this,ranking.class);
intent.putExtra("activity", 1);
startActivity(intent);

Activity 2

Intent intent = new Intent(this,ranking.class);
intent.putExtra("activity", 2);
startActivity(intent);

Ranking.class

Intent intent = getIntent();
int activityNumber = intent.getIntExtra("activity", 0);

if (activityNumber == 1) {
    //do something
} else{
    finish();
}