Android:onActivityResult 数据始终为空

Question

我已经在 StackOverflow 和 Google 上阅读过许多类似的情况，但没有一个对我的情况有帮助。我有两个 Activity ，A 和 B。A 调用 B 的 Activity 结果:

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.mnuMainSettings:
            startActivity(new Intent(ActivityMain.this, ActivitySettings.class));
            break;
        case R.id.mnuMainHelp:
            startActivity(new Intent(ActivityMain.this, ActivityHelp.class));
            break;
        case R.id.mnuMainEULA:
            Intent intent = new Intent(ActivityMain.this, ActivityDisclaimer.class);
            startActivityForResult(intent, 1);
            break;
    }
    return true;
}

Activity B:

public class ActivityDisclaimer extends Activity
{

    private WebView webView;

    public static final int ACTIVITY_RESULT_DISCLAIMER = 1;
    public static final String ACTIVITY_RESULT = "result";
    public static final int ACTIVITY_RESULT_OK = 1;
    public static final int ACTIVITY_RESULT_CANCELED = 2;


    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.disclaimer);

        webView = (WebView) findViewById(R.id.WebViewDisclaimer);
        webView.loadUrl("file:///android_asset/disclaimer.html");

    }

    public void onClickDisclaimerBtnAccept(View view) {
        Prefs prefs = new Prefs(this);
        prefs.setAcceptDisclaimer(true);
        prefs.commit();

        Intent returnIntent = new Intent();
        returnIntent.putExtra("result",true);
        setResult(Activity.RESULT_OK, returnIntent);        
        finish();
    }

    public void onClickDisclaimerBtnDecline(View view) {
        Prefs prefs = new Prefs(this);
        prefs.setAcceptDisclaimer(false);
        prefs.commit();

        Intent returnIntent = new Intent();
        returnIntent.putExtra("result",false);
        setResult(Activity.RESULT_OK, returnIntent);        
        finish();
    }

}

但是，我的onActivityResult方法，intent返回的数据总是NULL。

protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
        // For response from disclaimer activity
        if (requestCode == 1) {

            if (resultCode == Activity.RESULT_OK){
                if (null != intent) {
                    Boolean accepted = intent.getBooleanExtra("result", false);
                    Log.d(TAG, "Boolean Data: " + accepted.toString());
                    if (!accepted) finish();
                } else { Log.d(TAG, "RESULT OK, DATA NULL"); }
            }
            if (resultCode == Activity.RESULT_CANCELED){
                if (null != intent) {
                    Boolean accepted = intent.getBooleanExtra("result", false);
                    Log.d(TAG, "Boolean Data: " + accepted.toString());
                    finish();
                } else { Log.d(TAG, "RESULT CANCELED, DATA NULL"); }
            }

        }
    }//onActivityResult

“结果已取消，数据为空”是我得到的全部信息。我在这里错过了什么吗？也许我盯着这段代码看得太久了!

编辑:为了更具体地说明我的问题，为什么我得到一个空值？

Answer 1

热狗!回答我自己的问题，上面的代码很好。我终于在这里找到了答案:fragments startActivityForResult always return resultCode 0 and intent null on callback onActivityResult

总而言之，我的 manifest.xml 中有 android: launchMode="singleInstance"。我删除了这一行，现在一切正常!

真松了一口气!