在颤动中将数据从Firebase加载到DropdownButton中

// 引入Firebase SDK
<script src="https://www.gstatic.com/firebasejs/9.0.2/firebase-app.js"></script>
<script src="https://www.gstatic.com/firebasejs/9.0.2/firebase-database.js"></script>

// 初始化Firebase应用
<script>
  // Firebase配置信息
  var firebaseConfig = {
    apiKey: "YOUR_API_KEY",
    authDomain: "YOUR_AUTH_DOMAIN",
    databaseURL: "YOUR_DATABASE_URL",
    projectId: "YOUR_PROJECT_ID",
    storageBucket: "YOUR_STORAGE_BUCKET",
    messagingSenderId: "YOUR_MESSAGING_SENDER_ID",
    appId: "YOUR_APP_ID"
  };

  // 初始化Firebase应用
  firebase.initializeApp(firebaseConfig);
</script>

// 读取数据并加载到DropdownButton中
firebase.database().ref('data').on('value', function(snapshot) {
  var data = snapshot.val();
  var dropdownButton = document.getElementById('dropdownButton');

  // 清空DropdownButton中的选项
  dropdownButton.innerHTML = '';

  // 遍历数据并添加到DropdownButton中
  for (var key in data) {
    var option = document.createElement('option');
    option.value = key;
    option.text = data[key];
    dropdownButton.appendChild(option);
  }
});