Question

我已经启动了另一个活动，我希望将结果返回给调用它的活动，我已经阅读了一些教程并尝试了它，但是我收到了一些错误：

08-23 17:48:58.005: E/AndroidRuntime(581): java.lang.RuntimeException: Failure delivering result ResultInfo{who=Tab2, request=0, result=-1, data=Intent { cmp=com.organizer.medical.activities/.AddPatientActivity (has extras) }} to activity {com.organizer.medical.activities/com.organizer.medical.activities.Main}: java.lang.NullPointerException
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread.deliverResults(ActivityThread.java:2980)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread.handleSendResult(ActivityThread.java:3023)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread.access$1100(ActivityThread.java:123)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1177)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.os.Handler.dispatchMessage(Handler.java:99)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.os.Looper.loop(Looper.java:137)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread.main(ActivityThread.java:4424)
08-23 17:48:58.005: E/AndroidRuntime(581):  at java.lang.reflect.Method.invokeNative(Native Method)
08-23 17:48:58.005: E/AndroidRuntime(581):  at java.lang.reflect.Method.invoke(Method.java:511)
08-23 17:48:58.005: E/AndroidRuntime(581):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
08-23 17:48:58.005: E/AndroidRuntime(581):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-23 17:48:58.005: E/AndroidRuntime(581):  at dalvik.system.NativeStart.main(Native Method)
08-23 17:48:58.005: E/AndroidRuntime(581): Caused by: java.lang.NullPointerException
08-23 17:48:58.005: E/AndroidRuntime(581):  at com.organizer.medical.activities.PatientActivity.onActivityResult(PatientActivity.java:347)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityGroup.dispatchActivityResult(ActivityGroup.java:122)
08-23 17:48:58.005: E/AndroidRuntime(581):  at android.app.ActivityThread.deliverResults(ActivityThread.java:2976)
08-23 17:48:58.005: E/AndroidRuntime(581):  ... 11 more

以下是我的调用活动代码：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 0) {
      if (resultCode == RESULT_OK) {
        int cat = Integer.parseInt(getIntent().getExtras().get("category").toString());
        loadList(cat);
       }
 }
}

这是关于我的通话活动的oncreate（）：

startActivityForResult(new Intent(this, CalledActivity.class), ADD_PATIENT);

这是我的“被叫”活动的代码：

   setResult(RESULT_OK, getIntent().putExtra("category", status.isChecked()?1:2));
   finish();

顺便说一下，在我的被叫活动中，setResult()和finish()仅通过该被调用活动上的按钮onClick完成...

我真的不知道如何正确使用startActivityForResult()。请分享您对此的了解。

更新

事实证明我在onActivityResult（）上访问的意图导致了null异常错误，并且证明在该方法上传递的“date”var是要使用的那个：

int cat = Integer.parseInt(**data**.getExtras().get("category").toString());

Answer 1

你好这个例子返回一个字符串但是对于一个例子，它会没问题：

Intent intent = new Intent();
Bundle b = new Bundle();
b.putString("lastPath", this.myPath.getText().toString());
intent.putExtras(b);
setResult(SUCCESS_RETURN_CODE, intent);
finish();

要阅读值，请使用：

Bundle b = data.getExtras();
lastPath = b.getString("lastPath");

Answer 2

事实证明，我在onActivityResult（）上访问的意图导致了空异常错误，结果发现＆＃34; date＆＃34;传递给该方法的var就是这样使用的那个：

int cat = Integer.parseInt（ data .getExtras（）。get（＆＃34; category＆＃34;）。toString（））;

如何正确返回已启动活动的结果

2 个答案: