android的Intent返回值

@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);one=(EditText) this.findViewById(R.id.one);two=(EditText) this.findViewById(R.id.two);result=(EditText) this.findViewById(R.id.result);button=(Button)this.findViewById(R.id.button);button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {String a=one.getText().toString();String b=two.getText().toString();Intent intent=new Intent(MainActivity.this,OtherActivity.class);intent.putExtra("a", a);intent.putExtra("b", b);startActivityForResult(intent, 1);}});}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);Log.i("Main", "requestCode:"+requestCode+"resultCode:"+resultCode);if(resultCode==2){if(requestCode==1){result.setText(data.getStringExtra("tree"));}}}}

另一个activity

protected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.other);textView = (TextView) this.findViewById(R.id.msg);editText = (EditText) this.findViewById(R.id.three);button = (Button) this.findViewById(R.id.button2);Intent intent = getIntent();String a = intent.getStringExtra("a");String b = intent.getStringExtra("b");textView.setText(a + " + " + b + " =?");button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View arg0) {Intent intent=new Intent();String tree=editText.getText().toString();   intent.putExtra("tree",tree);   setResult(2, intent);   finish();}});}}