1.显式intent
Intent intent = new Intent(this,second.class); intent.putExtra("data"); startActivity(intent); Intent intent = getIntent(); String data = intent.getStringExtra("data"); 推荐写法： second： public static void actionStart(Context context, String data1, String data2) ｛ Intent intent = new Intent(context,second.class); intent.putExtra("param1", data1); intent.putExtra("param2", data2); context.startActivity(intent); ｝ first： second.actionStart(this,"data1","data2");2.startAcivityForResult
First: Intent intent = new Intent(this,second.class); startAcivityForResult(intent, 1); @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { switch (requestCode) { case 1: if (resultCode == RESULT_OK) { String returnedData = data.getStringExtra("data_return"); Log.d("FirstActivity", returnedData); } break; default: } } second: Intent intent = new Intent(); intent.putExtra("data_return","hello first"); setResult(RESULT_OK,intent); finish(); @Override public void onBackPressed() {//back键退出特殊情况 Intent intent = new Intent(); intent.putExtra("data_return", "hello first"); setResult(RESULT_OK, intent); finish(); }