三种不同方式启动activity

1，只启动Activity不做任何其他操作

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

2，启动Activity同时传递值

2.1 启动的Activity

Intent intent = new Intent(this, SecondActivity.class); intent.putExtra("user", "12345"); startActivity(intent);

2.2 被启动的Activity

Intent intent= getIntent(); String user=intent.getStringExtra("user");

此时值“12345”被传递到SecondActivity中；

3， 启动Activity，同时让被启动的Activity往回传值

3，1 启动的Activity

“101”为requestcode

Intent intent = new Intent(this, SecondActivity.class); startActivityForResult(intent, 101); //获得被传回来的值 @Override protected void onActivityResult(int requestCode, int resultCode, Intent data){ //data 是setResult(200, intent)方法中的intent； super.onActivityResult(requestCode, resultCode, data); if (requestCode==101&&resultCode==200) { String re= data.getStringExtra("result"); Log.i("TAG", "result:"+re); } }

3，2 被启动的Activity

Intent intent= new Intent(); intent.putExtra("result", "1678900"); //200 是resultcode； setResult(200, intent);