Firebase问题：图片仅传至Storage未同步至Realtime Database求助

我的应用允许用户上传图片并发布帖子，图片能正常上传到Firebase Storage的Posts Pictures文件夹，但Realtime Database里没有同步description、postImage、publisher、postId这些帖子数据。以下是AddActivity的代码：

class AddActivity : AppCompatActivity() {
    private var myUrl = ""
    private var imageUri: Uri? = null
    private var storagePostPicRef: StorageReference? = null
    companion object {
        val pickImage = 100
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_add)

        storagePostPicRef = FirebaseStorage.getInstance().reference.child("Posts Pictures")

        val savePostBtn = findViewById<ImageView>(R.id.save_post_btn)
        savePostBtn.setOnClickListener { uploadImage() }

        val gallery = Intent(Intent.ACTION_PICK, MediaStore.Images.Media.INTERNAL_CONTENT_URI)
        startActivityForResult(gallery, AccountSettingsActivity.pickImage)
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        val postpic = findViewById<ImageView>(R.id.image_post)
        if (resultCode == RESULT_OK && requestCode == AccountSettingsActivity.pickImage) {
            imageUri = data?.data
            postpic.setImageURI(imageUri)
        }
    }

    private fun uploadImage() {
        val descriptionEt = findViewById<EditText>(R.id.location_post)
        when {
            imageUri == null -> Toast.makeText(this, "请先选择图片", Toast.LENGTH_LONG).show()
            TextUtils.isEmpty(descriptionEt.text.toString()) -> Toast.makeText(this, "请填写描述", Toast.LENGTH_LONG).show()
            else -> {
                val progressDialog = ProgressDialog(this)
                progressDialog.setTitle("发布新帖子")
                progressDialog.setMessage("正在处理，请稍候...")
                progressDialog.show()

                val fileRef = storagePostPicRef!!.child(System.currentTimeMillis().toString() + ".jpg")
                val uploadTask = fileRef.putFile(imageUri!!)

                uploadTask.continueWithTask(Continuation<UploadTask.TaskSnapshot, Task<Uri>> { task ->
                    if (!task.isSuccessful) {
                        task.exception?.let {
                            progressDialog.dismiss()
                            throw it
                        }
                    }
                    return@Continuation fileRef.downloadUrl
                }).addOnCompleteListener { task ->
                    progressDialog.dismiss()
                    if (task.isSuccessful) {
                        val downloadUrl = task.result
                        myUrl = downloadUrl.toString()

                        val ref = FirebaseDatabase.getInstance().reference.child("Posts")
                        val postId = ref.push().key ?: run {
                            Toast.makeText(this, "生成帖子ID失败", Toast.LENGTH_SHORT).show()
                            return@addOnCompleteListener
                        }

                        val postMap = hashMapOf(
                            "postid" to postId,
                            "description" to descriptionEt.text.toString().toLowerCase(),
                            "publisher" to FirebaseAuth.getInstance().currentUser?.uid ?: "",
                            "postimage" to myUrl
                        )

                        // 用setValue创建新节点，而非updateChildren（update需要节点已存在）
                        ref.child(postId).setValue(postMap)
                            .addOnSuccessListener {
                                Toast.makeText(this, "帖子发布成功", Toast.LENGTH_LONG).show()
                                startActivity(Intent(this@AddActivity, MainActivity::class.java))
                                finish()
                            }
                            .addOnFailureListener { e ->
                                Toast.makeText(this, "发布失败：${e.message}", Toast.LENGTH_LONG).show()
                            }
                    } else {
                        Toast.makeText(this, "获取图片链接失败：${task.exception?.message}", Toast.LENGTH_LONG).show()
                    }
                }
            }
        }
    }
}

核心问题与修复说明 #

• 节点创建方式错误：原代码使用updateChildren(postMap)，这个方法仅会更新已存在的节点，不会创建新节点。改用setValue(postMap)才能在Realtime Database中创建新的帖子节点。
• 异常处理不完善：
  • 原代码中throw it在progressDialog.dismiss()之前，导致对话框无法关闭，调整顺序确保对话框先消失再抛出异常。
  • 添加addOnSuccessListener和addOnFailureListener监听数据库操作结果，明确告知用户成功/失败原因。
• 空指针风险规避：对postId和currentUser?.uid增加非空判断，避免崩溃。
• 请求码统一：建议将启动相册的请求码改为AddActivity.pickImage，避免依赖其他类的常量，减少耦合。

内容的提问来源于stack exchange，提问作者androidenthusiast