android Intent返回数据，回调数据，startActivityForResult用法

界面A

private static  final int REQUEST_REGION_PICK=1;//定义返回页面标识

1.开始发送请求：

     Intent intent = new Intent(A.this, B.class);
     startActivityForResult(intent, REQUEST_REGION_PICK);

2.接收B页面数据：

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {    
    super.onActivityResult(requestCode, resultCode, data);


if (requestCode == REQUEST_REGION_PICK) {
if (data != null) {

String date= data.getStringExtra("date");
}
}

    }

界面B

Intent intent = new Intent();
intent.putExtra("date",date);
setResult(Activity.RESULT_OK, intent); 

     Intent intent = new Intent(StoreService.this, F4_RegionPickActivity.class);
     startActivityForResult(intent, REQUEST_REGION_PICK);
     overridePendingTransition(R.anim.my_scale_action,R.anim.my_alpha_action);