Question

我尝试按照“Getting Started with Facebook Login for Web”中列出的步骤操作，但它们似乎无法正常工作。

我已按照此页面上的步骤操作;我检索了我的应用程序ID（步骤1），我添加了Facebook SDK for Javascript（步骤2）（减去通道URL，我在文档中的其他地方读到的是可选的，因为我正在离线工作而不是托管在服务器），然后我添加了登录代码（步骤3）。

我不确定为什么它不起作用。我收到控制台日志中的“无法加载资源”错误。

完整代码：

<html>
<head></head>
<body>
<div id="fb-root"></div>
<script>
  window.fbAsyncInit = function() {
  FB.init({
    appId      : '1233456789', // App ID
    //channelUrl : '//WWW.YOUR_DOMAIN.COM/channel.html', // Channel File
    status     : true, // check login status
    cookie     : true, // enable cookies to allow the server to access the session
    xfbml      : true  // parse XFBML
  });

  // Here we subscribe to the auth.authResponseChange JavaScript event. This event is fired
  // for any auth related change, such as login, logout or session refresh. This means that
  // whenever someone who was previously logged out tries to log in again, the correct case below 
  // will be handled. 
  FB.Event.subscribe('auth.authResponseChange', function(response) {
    // Here we specify what we do with the response anytime this event occurs. 
    if (response.status === 'connected') {
      // The response object is returned with a status field that lets the app know the current
      // login status of the person. In this case, we're handling the situation where they 
      // have logged in to the app.
      testAPI();
    } else if (response.status === 'not_authorized') {
      // In this case, the person is logged into Facebook, but not into the app, so we call
      // FB.login() to prompt them to do so. 
      // In real-life usage, you wouldn't want to immediately prompt someone to login 
      // like this, for two reasons:
      // (1) JavaScript created popup windows are blocked by most browsers unless they 
      // result from direct user interaction (such as a mouse click)
      // (2) it is a bad experience to be continually prompted to login upon page load.
      FB.login();
    } else {
      // In this case, the person is not logged into Facebook, so we call the login() 
      // function to prompt them to do so. Note that at this stage there is no indication
      // of whether they are logged into the app. If they aren't then they'll see the Login
      // dialog right after they log in to Facebook. 
      // The same caveats as above apply to the FB.login() call here.
      FB.login();
    }
  });
  };

  // Load the SDK asynchronously
  (function(d){
   var js, id = 'facebook-jssdk', ref = d.getElementsByTagName('script')[0];
   if (d.getElementById(id)) {return;}
   js = d.createElement('script'); js.id = id; js.async = true;
   js.src = "//connect.facebook.net/en_US/all.js";
   ref.parentNode.insertBefore(js, ref);
  }(document));

  // Here we run a very simple test of the Graph API after login is successful. 
  // This testAPI() function is only called in those cases. 
  function testAPI() {
    console.log('Welcome!  Fetching your information.... ');
    FB.api('/me', function(response) {
      console.log('Good to see you, ' + response.name + '.');
    });
  }
</script>
<!--Below we include the Login Button social plugin. This button uses the JavaScript SDK to-->
<!--present a graphical Login button that triggers the FB.login() function when clicked.-->
<fb:login-button show-faces="true" width="200" max-rows="1"></fb:login-button>
</body>
</html>

Answer 1

如果仔细观察，Facebook SDK下载行将以//开头，而不是http://或https://。这意味着将使用嵌入页面的相同协议下载脚本。您正在打开一个本地文件，该文件在导航栏中显示为file://，因此浏览器会尝试通过file://下载SDK并失败。

长话短说：在https:之前添加//，如下所示：

js.src = "https://connect.facebook.net/en_US/all.js"

更长的解决方案（但更清晰）：使用本地开发服务器。如果您的PC上安装了PHP 5.4，请打开命令行，导航到项目文件夹，然后启动：

php -S localhost:8080

打开浏览器并在地址栏中输入localhost:8080。

我已经按照“Facebook登录入门”中的步骤进行了操作，但是为Javascript添加Facebook SDK似乎不起作用

1 个答案: