问管理android的后台

EN

// Launch A (our dispatcher)
Intent intent = new Intent(this, A.class);
// Setting CLEAR_TOP ensures that all other activities on top of A will be finished
//  and setting SINGLE_TOP ensures that a new instance of A will not
//  be created (the existing instance will be reused and onNewIntent() will be called)
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_SINGLE_TOP);
// Add an extra telling A that it should launch B
intent.putExtra("startB", true);
startActivity(intent);

@Override
protected void onNewIntent(Intent intent) {
    if (intent.hasExtra("startB")) {
        // Need to start B from here
        startActivity(new Intent(this, B.class));
    }
}

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