活动之间的两种数据绑定方式

Question

我有2个活动，并且需要main Activity将一些数据发送到second Activity然后第二个活动分析此数据并发送回响应，因此我具有以下2个代码：

Main Activity ：

    import static tk.zillion.mobile.SecondActivity.EXTRA_STUFF;

  public class MainActivity extends Activity {
    private static int PICK_CONTACT_REQUEST = 0;
   private static final int SECOND_ACTIVITY_RESULT_CODE = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

   // Start the SecondActivity
    Intent intent = new Intent(MainActivity.this, SecondActivity.class);
    intent.putExtra(Intent.EXTRA_TEXT, "my text");
    startActivityForResult(intent, SECOND_ACTIVITY_RESULT_CODE);

    finish();
  }

// This method is called when the second activity finishes
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    Toast.makeText(this, "I'm the Main activity", Toast.LENGTH_SHORT).show();
    // check that it is the SecondActivity with an OK result
    if (requestCode == SECOND_ACTIVITY_RESULT_CODE) {
        if (resultCode == RESULT_OK) {

            // get String data from Intent
            String returnString = data.getStringExtra(EXTRA_STUFF);

            // set text view with string
            Toast.makeText(this, "I'm the Main activity", Toast.LENGTH_SHORT).show();
        }
    }
}

Second Activity如下：

public class SecondActivity extends Activity {

static final String EXTRA_STUFF = "tk.zillion.mobile.EXTRA_STUFF";
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Intent intent = new Intent();
    String s = getIntent().getStringExtra(Intent.EXTRA_TEXT);
    Toast.makeText(this, "I'm the second activity " + s , Toast.LENGTH_SHORT).show();

    Bundle basket =new Bundle();
    basket.putString(EXTRA_STUFF, s);
    intent.putExtras(basket);
    setResult(RESULT_OK, intent);
    finish();
  }
}

第二个活动已正确触发，并从主要活动接收了数据，但是一旦将数据发送回，则不会触发onActivityResult ！

我该如何解决？ 谢谢

Answer 1

不要在startActivityForResult之后调用finish（），否则启动第二个实例的MainActivity实例将被销毁

Answer 2

删除startActivityForResult（）之后的finish（）调用。 您可以防止即将来临的活动返回结果，因为您从back任务中使用finish（）删除了MainActivity。