脸书 API。 Android 项目的 Java 代码不正确。

Question

实验室遇到严重问题，而且我不是唯一一个。我的模拟器在所有 Facebook 示例应用程序中运行良好。 FacebookSDK 和 HelloFacebookSample 项目都可以正常工作。代码中的某些内容不正确。所有 xml 和清单编码都是正确的。我确信这是Java代码中的东西。它编译，提示登录，然后询问权限，然后崩溃。

import org.json.JSONArray;
import org.json.JSONObject;
import android.app.Activity;
import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import com.facebook.HttpMethod;
import com.facebook.Request;
import com.facebook.Response;
import com.facebook.Session;
import com.facebook.Session.StatusCallback;
import com.facebook.model.GraphObject;
import com.facebook.SessionState;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    if (savedInstanceState == null) {
        getFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment()).commit();
    }
}

public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    Session.getActiveSession().onActivityResult(this, requestCode,
            resultCode, data);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {

    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

/**
 * A placeholder fragment containing a simple view.
 */
public static class PlaceholderFragment extends Fragment {

    public PlaceholderFragment() {
    }

    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_main, container,
                false);
        final TextView newsFeedTextView = (TextView) rootView
                .findViewById(R.id.newsFeed);

        StatusCallback mCallback = new Session.StatusCallback() {

            @Override
            public void call(Session session, SessionState state,
                    Exception exception) {

                if (session.isOpened()) {

                    /* make the API call */
                    new Request(session, "/GmitClubsandsocieties/feed", null, 
                            HttpMethod.GET, new Request.Callback() {

                                @Override
                                public void onCompleted(Response response) {
                                    /* check logcat for responce */
                                    System.out.println(response);

                                    newsFeedTextView
                                            .setText(parseDataFromFQLResponse(response));
                                }
                            }).executeAsync();
                }

            }
        };
        Session.OpenRequest request = new Session.OpenRequest(getActivity());
        // request.setPermissions(Arrays.asList("read_stream"));
        request.setCallback(mCallback);

        // get active session
        Session mFacebookSession = Session.getActiveSession();
        if (mFacebookSession == null || mFacebookSession.isClosed()) {
            mFacebookSession = new Session(getActivity());
        }
        // mFacebookSession.openForRead(request);
        mFacebookSession.openForRead(request);
        return rootView;
    }

}

private static String parseDataFromFQLResponse(Response response) {
    StringBuilder responseText = new StringBuilder(" ");
    try {
        GraphObject go = response.getGraphObject();
        JSONObject jso = go.getInnerJSONObject();
        JSONArray arr = jso.getJSONArray( "data" );
        for (int i = 0; i < (arr.length()); i++) {
            JSONObject json_obj = arr.getJSONObject(i);
            responseText.append(String.format("Message: %s\n\n",
                    json_obj.getString("message")));
        }
    } catch (Throwable t) {
        t.printStackTrace();
    }
    return responseText.toString();
}

}

这是日志文件：

04-24 09:57:28.453: D/AndroidRuntime(2574): Shutting down VM
04-24 09:57:28.453: W/dalvikvm(2574): threadid=1: thread exiting with uncaught exception (group=0xb2ae0ba8)
04-24 09:57:28.513: E/AndroidRuntime(2574): FATAL EXCEPTION: main
04-24 09:57:28.513: E/AndroidRuntime(2574): Process: ie.gmit.facebooknewsfeed, PID: 2574
04-24 09:57:28.513: E/AndroidRuntime(2574): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=64206, result=-1, data=Intent { (has extras) }} to activity {ie.gmit.facebooknewsfeed/ie.gmit.facebooknewsfeed.MainActivity}: java.lang.NullPointerException
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread.deliverResults(ActivityThread.java:3365)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread.handleSendResult(ActivityThread.java:3408)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread.access$1300(ActivityThread.java:135)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1244)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.os.Handler.dispatchMessage(Handler.java:102)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.os.Looper.loop(Looper.java:136)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread.main(ActivityThread.java:5017)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at java.lang.reflect.Method.invokeNative(Native Method)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at java.lang.reflect.Method.invoke(Method.java:515)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at dalvik.system.NativeStart.main(Native Method)
04-24 09:57:28.513: E/AndroidRuntime(2574): Caused by: java.lang.NullPointerException
04-24 09:57:28.513: E/AndroidRuntime(2574):     at ie.gmit.facebooknewsfeed.MainActivity.onActivityResult(MainActivity.java:40)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.Activity.dispatchActivityResult(Activity.java:5423)
04-24 09:57:28.513: E/AndroidRuntime(2574):     at android.app.ActivityThread.deliverResults(ActivityThread.java:3361)
04-24 09:57:28.513: E/AndroidRuntime(2574):     ... 11 more
04-24 09:57:32.283: I/Process(2574): Sending signal. PID: 2574 SIG: 9

Answer 1

您的data 参数可能未正确填充。在onActivityResult
添加行
Bundle bundle = data.getExtras();