开发笔记:通过kotlin..通过firebase从数据库读取数据到RecyclerView的麻烦

我很难通过firebase从数据库中读取数据。代码假设从数据库读取数据到RecyclerView ..但没有工作..

该应用程序是没有错误或错误的工作，如果在recyclerView内写入一些数据将毫无困难地进入数据库，但在recyclerView中没有数据显示..

............

MainActivity代码>>>

class MainVote : AppCompatActivity()
override fun onCreate(savedInstanceState: Bundle?)
super.onCreate(savedInstanceState)
setContentView(R.layout.main_vote)
RecyclerView.layoutManager = LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false)
val votes = ArrayList()
// Here start reading data code from database in firebase
val db= FirebaseDatabase.getInstance().getReference()
db.child("votedata").addValueEventListener(object : ValueEventListener
override fun onDataChange(p0: DataSnapshot?)
val values = p0!!.value as HashMap
for (k in values.keys)
val data = values[k] as HashMap
votes.add(
VotePublic(
data["quesVote"] as String ,
data["vote11"] as String ,
data["vote22"] as String ,
data["vote33"] as String ,
data["vote44"] as String
))

val myadaper = CastumAdapter(votes,this)
RecyclerView.adapter = myadaper

override fun onCancelled(p0: DatabaseError?)

)


CustomAdapter类.. >>

class CastumAdapter(val votelist: ArrayList, val context: ValueEventListener) : RecyclerView.Adapter ()
override fun onCreateViewHolder(p0: ViewGroup, p1: Int): MyViewHolder
val view = LayoutInflater.from(p0.context).inflate(R.layout.raw_re2,p0,false)
return MyViewHolder(view)
override fun getItemCount(): Int
return votelist.size
override fun onBindViewHolder(holder: MyViewHolder, p1: Int)
val votepublic : VotePublic = votelist[p1]
holder.setData(votepublic, p1)
inner class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView)
// some code here..
.
.
.
.
fun setData(datavote: VotePublic?, pos: Int)
this.currentHobby = datavote
this.currentPosition = pos




这是数据库结构的JSON示例：


"project_info":
"project_number": "836053259827",
"firebase_url": "https://vote-app-****",
"project_id": "vote-app-****",
"storage_bucket": "vote-app-****.appspot.com"
,
"client": [
"client_info":
"mobilesdk_app_id": "1:836053259827:android:****",
"android_client_info":
"package_name": "com.example.dell.vote1"

,
"oauth_client": [

"client_id": "****-hlqj7at8n5tvhmllgr82p7k9ssvl3f8l.apps.googleusercontent.com",
"client_type": 1,
"android_info":
"package_name": "com.example.dell.vote1",
"certificate_hash": "****"

,

"client_id": "****-glt9h6b98k7bc2m1390rbogn7tioo70a.apps.googleusercontent.com",
"client_type": 3

],
"api_key": [

"current_key": "****_-9t6BVPeE4g8eQ"

],
"services":
"analytics_service":
"status": 1
,
"appinvite_service":
"status": 2,
"other_platform_oauth_client": [

"client_id": "****-glt9h6b98k7bc2m1390rbogn7tioo70a.apps.googleusercontent.com",
"client_type": 3

]
,
"ads_service":
"status": 2



],
"configuration_version": "1"