<!-- 微信权限-->
<uses-permission android:name="android.permission.INTERNET"/> 
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/> 
<uses-permission android:name="android.permission.READ_PHONE_STATE"/> 
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> 

private void loginToWeiXin(){
  IWXAPI mApi = WXAPIFactory.createWXAPI(this, WXEntryActivity.WEIXIN_APP_ID, true);
  mApi.registerApp(WXEntryActivity.WEIXIN_APP_ID);

  if (mApi != null && mApi.isWXAppInstalled()) {
   SendAuth.Req req = new SendAuth.Req();
   req.scope = "snsapi_userinfo";
   req.state = "wechat_sdk_demo_test_neng";
   mApi.sendReq(req);
  } else
   Toast.makeText(this, "用户未安装微信", Toast.LENGTH_SHORT).show();
 }

package com.xxx.xxxx.android.wxapi;
/**
 * 微信登录页面
 * @author kevin_chen 2016-12-10 下午19:03:45
 * @version v1.0
 */
public class WXEntryActivity extends Activity implements IWXAPIEventHandler {
 private static final String APP_SECRET = "填写自己的AppSecret";
 private IWXAPI mWeixinAPI;
 public static final String WEIXIN_APP_ID = "填写自己的APP_id";
 private static String uuid;


 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  mWeixinAPI = WXAPIFactory.createWXAPI(this, WEIXIN_APP_ID, true);
  mWeixinAPI.handleIntent(this.getIntent(), this);
 }

 @Override
 protected void onNewIntent(Intent intent) {
  super.onNewIntent(intent);
  setIntent(intent);
  mWeixinAPI.handleIntent(intent, this);//必须调用此句话
 }

 //微信发送的请求将回调到onReq方法
 @Override
 public void onReq(BaseReq req) {
  LogUtils.log("onReq");
 }

 //发送到微信请求的响应结果
 @Override
 public void onResp(BaseResp resp) {
  LogUtils.log("onResp");
  switch (resp.errCode) {
  case BaseResp.ErrCode.ERR_OK:
   LogUtils.log("ERR_OK");
   //发送成功
   SendAuth.Resp sendResp = (SendAuth.Resp) resp;
   if (sendResp != null) {
    String code = sendResp.code;
    getAccess_token(code);
   }
   break;
  case BaseResp.ErrCode.ERR_USER_CANCEL:
   LogUtils.log("ERR_USER_CANCEL");
   //发送取消
   break;
  case BaseResp.ErrCode.ERR_AUTH_DENIED:
   LogUtils.log("ERR_AUTH_DENIED");
   //发送被拒绝
   break;
  default:
   //发送返回
   break;
  }

 }

 /**
  * 获取openid accessToken值用于后期操作
  * @param code 请求码
  */
 private void getAccess_token(final String code) {
  String path = "https://api.weixin.qq.com/sns/oauth2/access_token?appid="
    + WEIXIN_APP_ID
    + "&secret="
    + APP_SECRET
    + "&code="
    + code
    + "&grant_type=authorization_code";
  LogUtils.log("getAccess_token：" + path);
  //网络请求，根据自己的请求方式
  VolleyRequest.get(this, path, "getAccess_token", false, null, new VolleyRequest.Callback() {
   @Override
   public void onSuccess(String result) {
    LogUtils.log("getAccess_token_result:" + result);
    JSONObject jsonObject = null;
    try {
     jsonObject = new JSONObject(result);
     String openid = jsonObject.getString("openid").toString().trim();
     String access_token = jsonObject.getString("access_token").toString().trim();
     getUserMesg(access_token, openid);
    } catch (JSONException e) {
     e.printStackTrace();
    }

   }

   @Override
   public void onError(String errorMessage) {

   }
  });
 }


 /**
  * 获取微信的个人信息
  * @param access_token
  * @param openid
  */
 private void getUserMesg(final String access_token, final String openid) {
  String path = "https://api.weixin.qq.com/sns/userinfo?access_token="
    + access_token
    + "&openid="
    + openid;
  LogUtils.log("getUserMesg：" + path);
  //网络请求，根据自己的请求方式
  VolleyRequest.get(this, path, "getAccess_token", false, null, new VolleyRequest.Callback() {
   @Override
   public void onSuccess(String result) {
    LogUtils.log("getUserMesg_result:" + result);
    JSONObject jsonObject = null;
    try {
     jsonObject = new JSONObject(result);
     String nickname = jsonObject.getString("nickname");
     int sex = Integer.parseInt(jsonObject.get("sex").toString());
     String headimgurl = jsonObject.getString("headimgurl");
     
     LogUtils.log("用户基本信息:");
     LogUtils.log("nickname:" + nickname);
     LogUtils.log("sex:" + sex);
     LogUtils.log("headimgurl:" + headimgurl);
    } catch (JSONException e) {
     e.printStackTrace();
    }
    finish();
   }

   @Override
   public void onError(String errorMessage) {

   }
  });
 }

}

<!--注册微信回调 WXEntryActivity -->
<activity
 android:name=".wxapi.WXEntryActivity"
 android:exported="true"
 android:label="@string/app_name"
 android:launchMode="singleTop"
 android:theme="@android:style/Theme.Translucent" />