Question

完成＆＃34;用户登录＆＃34;本教程的一部分，我确保检查＆＃34; http://localhost:5000＆＃34;看到我的登录功能正常。我做了＃34;阅读消息＆＃34;部分现在我没有看到任何登录信息。

我也没有看到我导入的任何消息...... FriendlyChat.prototype.initFirebase = function（）{ // Firebase SDK功能的快捷方式。 this.auth = firebase.auth（）; this.database = firebase.database（）; this.storage = firebase.storage（）; //启动Firebase身份验证并侦听身份验证状态更改。 this.auth.onAuthStateChanged（this.onAuthStateChanged.bind（本））; // TODO（DEVELOPER）：初始化Firebase。 };

// Loads chat messages history and listens for upcoming ones.
FriendlyChat.prototype.loadMessages = function() {
  // TODO(DEVELOPER): Load and listens for new messages.
// Reference to the /messages/ database path.
  this.messagesRef = this.database.ref('messages');
  // Make sure we remove all previous listeners.
  this.messagesRef.off();

  // Loads the last 12 messages and listen for new ones.
    var setMessage = function(data) {
        var val = data.val();
        this.displayMessage(data.key, val.name, val.text, val.photoUrl, val.imageUrl);
  }.bind(this);
  this.messagesRef.limitToLast(12).on('child_added', setMessage);
  this.messagesRef.limitToLast(12).on('child_changed', setMessage);
};

};

// Saves a new message on the Firebase DB.
FriendlyChat.prototype.saveMessage = function(e) {
  e.preventDefault();
  // Check that the user entered a message and is signed in.
  if (this.messageInput.value && this.checkSignedInWithMessage()) {

    // TODO(DEVELOPER): push new message to Firebase.

  }
};
...
FriendlyChat.prototype.signIn = function() {
  // Sign in Firebase using popup auth and Google as the identity provider.
  var provider = new firebase.auth.GoogleAuthProvider();
  this.auth.signInWithPopup(provider);

  // TODO(DEVELOPER): Sign in Firebase with credential from the Google user.
};

// Signs-out of Friendly Chat.
FriendlyChat.prototype.signOut = function() {
  // TODO(DEVELOPER): Sign out of Firebase.
  // Sign out of Firebase.
     this.auth.signOut();
};
riendlyChat.prototype.onAuthStateChanged = function(user) {
  if (user) { // User is signed in!
    // Get profile pic and user's name from the Firebase user object.
    var profilePicUrl = user.photoURL;   // TODO(DEVELOPER): Get profile pic.
    var userName = user.displayName;        // TODO(DEVELOPER): Get user's name.

    // Set the user's profile pic and name.
    this.userPic.style.backgroundImage = 'url(' + profilePicUrl + ')';
    this.userName.textContent = userName;

    // Show user's profile and sign-out button.
    this.userName.removeAttribute('hidden');
    this.userPic.removeAttribute('hidden');
    this.signOutButton.removeAttribute('hidden');

    // Hide sign-in button.
    this.signInButton.setAttribute('hidden', 'true');

    // We load currently existing chant messages.
    this.loadMessages();
  } else { // User is signed out!
    // Hide user's profile and sign-out button.
    this.userName.setAttribute('hidden', 'true');
    this.userPic.setAttribute('hidden', 'true');
    this.signOutButton.setAttribute('hidden', 'true');

    // Show sign-in button.
    this.signInButton.removeAttribute('hidden');
  }
};

// Returns true if user is signed-in. Otherwise false and displays a message.
FriendlyChat.prototype.checkSignedInWithMessage = function() {
  /* TODO(DEVELOPER): Check if user is signed-in Firebase. */
   // Return true if the user is signed in Firebase
  if (this.auth.currentUser) {
    return true;
  }
  // Display a message to the user using a Toast.
  var data = {
    message: 'You must sign-in first',
    timeout: 2000
  };
  this.signInSnackbar.MaterialSnackbar.showSnackbar(data);
  return false;
};

这些是我必须改变的功能。我可以做些什么来覆盖我之前正确的登录实现，也无法访问我导入的数据库消息？

Answer 1

您可以随时根据包含codelab完成的工作代码的web文件夹检查您的代码。

特别是你有这个：

// Sets up shortcuts to Firebase features and initiate firebase auth.
FriendlyChat.prototype.initFirebase = function() {
  // Shortcuts to Firebase SDK features.
  this.auth = firebase.auth();
  this.database = firebase.database();
  this.storage = firebase.storage();
  // Initiates Firebase auth and listen to auth state changes.
  this.auth.onAuthStateChanged(this.onAuthStateChanged.bind(this));
};

那：

// Triggers when the auth state change for instance when the user signs-in or signs-out.
FriendlyChat.prototype.onAuthStateChanged = function(user) {
  if (user) { // User is signed in!
    // Get profile pic and user's name from the Firebase user object.
    var profilePicUrl = user.photoURL;
    var userName = user.displayName;

    // Set the user's profile pic and name.
    this.userPic.style.backgroundImage = 'url(' + (profilePicUrl || '/images/profile_placeholder.png') + ')';
    this.userName.textContent = userName;

    // Show user's profile and sign-out button.
    this.userName.removeAttribute('hidden');
    this.userPic.removeAttribute('hidden');
    this.signOutButton.removeAttribute('hidden');

    // Hide sign-in button.
    this.signInButton.setAttribute('hidden', 'true');

    // We load currently existing chant messages.
    this.loadMessages();
  } else { // User is signed out!
    // Hide user's profile and sign-out button.
    this.userName.setAttribute('hidden', 'true');
    this.userPic.setAttribute('hidden', 'true');
    this.signOutButton.setAttribute('hidden', 'true');

    // Show sign-in button.
    this.signInButton.removeAttribute('hidden');
  }
};

上述两个功能将确保UI刷新，具体取决于用户登录或注销（因此隐藏/显示＆＃34;登录＆＃34;按钮）。

对于您的数据库消息，只有在登录正常后才能显示，所以希望修复上述内容有助于显示您的消息。

Answer 2

github 上的讨论可能会有所帮助：https://github.com/firebase/friendlychat/issues/134

如果控制登录相关<div>和<button>的隐藏属性的代码无法运行，则登录代码将默认隐藏。

Firebase登录无法正常运行

2 个答案: