Question

主要问题在于onActivityResult（）方法。它无法将结果发送回片段。它会生成nullpointerexception。

MainActivity Class

    package com.example.kunalgoyal.login;
    import android.content.Intent;
    import android.os.Bundle;
    import android.support.v7.app.ActionBarActivity;
    public class MainActivity extends ActionBarActivity  {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
        }
        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
            Fragment4 f=(Fragment4)getSupportFragmentManager().findFragmentById(R.id.fragment);
            if(f !=null)
            {
                f.onActivityResult(requestCode,resultCode,data);
            }

        }
    }

片段类

package com.example.kunalgoyal.login;

import android.app.Activity;
import android.content.Intent;
import android.content.IntentSender;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Scope;
import com.google.android.gms.plus.People;
import com.google.android.gms.plus.Plus;
import com.google.android.gms.plus.model.people.Person;


public class Fragment4 extends android.support.v4.app.Fragment implements GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener,
        View.OnClickListener, ResultCallback<People.LoadPeopleResult> {   private GoogleApiClient mGoogleApiClient;
    private static final int RC_SIGN_IN = 0;
    private boolean mIntentInProgress;
    private boolean mSignInClicked;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        mGoogleApiClient = new GoogleApiClient.Builder(getActivity().getApplicationContext())
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(Plus.API)
                .addScope(new Scope("profile"))
                .build();

    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment

        View v = inflater.inflate(R.layout.fragment_fragment4, container,false);
        v.findViewById(R.id.sign_in_button).setOnClickListener(this);

        return v;

    }


    @Override
    public void onStart() {
        super.onStart();
        mGoogleApiClient.connect();
    }

    @Override
    public void onStop() {
        super.onStop();
        mGoogleApiClient.disconnect();
    }
    @Override
    public void onConnected(Bundle bundle) {
        mSignInClicked = false;
        Log.i("onConnected", "aaaaaaaaaaaaaaa");

        Plus.PeopleApi.loadVisible(mGoogleApiClient, null).setResultCallback(this);
        if (Plus.PeopleApi.getCurrentPerson(mGoogleApiClient) != null) {
            Person currentPerson = Plus.PeopleApi.getCurrentPerson(mGoogleApiClient);
            String personName = currentPerson.getDisplayName();
            Person.Image personPhoto = currentPerson.getImage();
            String personGooglePlusProfile = currentPerson.getUrl();
            Toast.makeText(getActivity().getApplicationContext(), " "+ personName + ", ", Toast.LENGTH_LONG).show();
        }
    }

    @Override
    public void onConnectionSuspended(int i) {
        mGoogleApiClient.connect();
        Log.i("on Suspended", "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
    }

    @Override
    public void onClick(View view) {
        if (view.getId() == R.id.sign_in_button && !mGoogleApiClient.isConnecting()) {
            mSignInClicked = true;
            mGoogleApiClient.connect();
            Log.i("on Click", "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
        }
    }
    @Override
    public void onActivityResult(int requestCode, int responseCode, Intent intent) {
        if (requestCode == RC_SIGN_IN) {
            if (responseCode != Activity.RESULT_OK) {
                mSignInClicked = false;
            }
            mIntentInProgress = false;
            if (!mGoogleApiClient.isConnected()) {
                mGoogleApiClient.reconnect();
            }
        }
    }
    @Override
    public void onConnectionFailed(ConnectionResult result) {
        if (!mIntentInProgress) {
            if (mSignInClicked && result.hasResolution()) {
                // The user has already clicked 'sign-in' so we attempt to resolve all
                // errors until the user is signed in, or they cancel.
                try {
                    result.startResolutionForResult(getActivity(), RC_SIGN_IN);
                    mIntentInProgress = true;
                } catch (IntentSender.SendIntentException e) {
                    // The intent was canceled before it was sent.  Return to the default
                    // state and attempt to connect to get an updated ConnectionResult.
                    mIntentInProgress = false;
                    mGoogleApiClient.connect();
                }
            }
        }
    }

    @Override
    public void onResult(People.LoadPeopleResult peopleDaa) {

    }
}

activity_main.xml中

<fragment xmlns:android="http://schemas.android.com/apk/res/android"
 android:name="com.example.kunalgoyal.login.Fragment4"
android:id="@+id/headlines_fragment"
android:layout_weight="1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />

fragment_fragment4.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" tools:context="com.example.kunalgoyal.login.Fragment4"
    android:id="@+id/fragment">


    <com.google.android.gms.common.SignInButton
        android:id="@+id/sign_in_button"
        android:layout_width="150dp"
        android:layout_height="90dp" />

</FrameLayout>

清单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.kunalgoyal.login" >
    <meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
    <uses-permission android:name="android.permission.USE_CREDENTIALS" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Answer 1

在我的应用中实施Google plus登录时遇到同样的问题最后一个解决方案对我来说很好，将 GoogleApiClient 对象设为静态对象。

希望它有所帮助。

onActivityResult（）无法发回结果

1 个答案: