我的应用程序显示 RecyclerView 但现在显示它的项目

Question

实际上我的应用程序显示 RecyclerView 但现在显示它的项目。之后我在字段中输入数据并单击 btn_add，它们成功保存在数据库中，但是当我单击我的应用程序中的 Btn-show 按钮显示它们时，一切正常并且它显示 recyclerview，但它只显示“id”项，其他项不显示。

SecondActivity.java

    class SecondActivity : AppCompatActivity() {

    private var dbHandle:DatabaseHandler?=null

    lateinit var btn_show:Button
    lateinit var rec:RecyclerView
    lateinit var btn_add:Button


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

        dbHandle = DatabaseHandler(this)

        btn_show=findViewById(R.id.show)
        rec=findViewById(R.id.rec)
        btn_add=findViewById(R.id.add)
        var edit_name=findViewById<EditText>(R.id.edit_name)
        var edit_age =findViewById<EditText>(R.id.edit_age)
        var edit_heigth=findViewById<EditText>(R.id.edit_heigth)
        var edit_city=findViewById<EditText>(R.id.edit_city)
        var edit_b_day=findViewById<EditText>(R.id.edit_b_day)
        var edit_b_city=findViewById<EditText>(R.id.edit_b_city)
        var edit_education=findViewById<EditText>(R.id.edit_education)


        val actors=Actors()
        actors.Name=edit_name.text.toString()
        actors.Age=edit_age.text.toString()
        actors.heigth=edit_heigth.text.toString()
        actors.city=edit_city.text.toString()
        actors.bdate=edit_b_day.text.toString()
        actors.bcity=edit_b_city.text.toString()
        actors.education=edit_education.text.toString()

        btn_add.setOnClickListener {
            var success = false
            success=dbHandle!!.addActors(actors)
            Toast.makeText(this,"result: $success", Toast.LENGTH_SHORT).show()
        }




        btn_show.setOnClickListener {
            rec.layoutManager = LinearLayoutManager(this)
            val myList= dbHandle!!.getAllActorsList()
            rec.adapter=RecyclerAdapter(myList,this)}

    }

我的class:

    var Name: String = ""
    var Age: String = ""
    var heigth: String = ""
    var city: String = ""
    var bdate:String = ""
    var bcity: String = ""
    var education: String =""

    constructor()
    constructor(
        id: Int?,
        Name: String,
        Age: String,
        heigth: String,
        city: String,
        b_date: String,
        b_city: String,
        education: String,
    ) {
        this.id = id
        this.Name = Name
        this.Age = Age
        this.heigth = heigth
        this.city = city
        this.bdate = b_date
        this.bcity = b_city
        this.education = education
    }

    constructor(
        Name: String,
        Age: String,
        heigth: String,
        city: String,
        b_date: String,
        b_city: String,
        education: String,
    ) {
        this.Name = Name
        this.Age = Age
        this.heigth = heigth
        this.city = city
        this.bdate = b_date
        this.bcity = b_city
        this.education = education

回收器适配器：

    class RecyclerAdapter( val items:ArrayList<Actors>, val context1: Context):RecyclerView.Adapter<viewHolder>() {
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): viewHolder {

        return viewHolder(LayoutInflater.from(context1).inflate(R.layout.recycler_item,parent,false))

    }

    override fun onBindViewHolder(holder: viewHolder, position: Int) {

        holder!!.name.text = items.get(position).Name
        holder!!.age.text = items.get(position).Age
        holder!!.id.text = items.get(position).id.toString()
        holder!!.height.text = items.get(position).heigth
        holder!!.city.text = items.get(position).city
        holder!!.bdate.text = items.get(position).bdate
        holder!!.bcity.text = items.get(position).bcity
        holder!!.education.text = items.get(position).education



        holder.itemView.setOnClickListener {
            Toast.makeText(context1, "position:$position....",Toast.LENGTH_SHORT).show()

        }

    }

    override fun getItemCount(): Int {
        return items.size
    }
}




class viewHolder(view: View):RecyclerView.ViewHolder(view){

    val name = view.findViewById<TextView>(R.id.name)
    var age =view.findViewById<TextView>(R.id.age)
    val height = view.findViewById<TextView>(R.id.height)
    val id = view.findViewById<TextView>(R.id.id)
    var city =view.findViewById<TextView>(R.id.city)
    val bdate = view.findViewById<TextView>(R.id.b_date)
    var bcity =view.findViewById<TextView>(R.id.b_city)
    val education = view.findViewById<TextView>(R.id.education)

DatabseHandler class:


    class DatabaseHandler(context: Context):SQLiteOpenHelper(context,DB_Name,null,DB_Version){

    companion object{

        private val DB_Name = "DB"
        private val DB_Version=1
        private val TABLE_NAME="actors"
        private val ID ="id"
        private val Name = "Name"
        private val Age = "Age"
        private val Heigth="Height"
        private val City = "City"
        private val b_date ="bDate"
        private val b_city="bCity"
        private val Education = "Education"
    }

    override fun onCreate(p0: SQLiteDatabase?) {

        var CREATE_TABLE = "CREATE TABLE $TABLE_NAME" + "($ID INTEGER PRIMARY KEY, $Name TEXT,$Age TEXT, $Heigth TEXT, $City TEXT, $b_date TEXT, $b_city TEXT,$Education TEXT)"
        p0?.execSQL(CREATE_TABLE)
    }



    fun addActors(actors:Actors): Boolean {

        val po = this.writableDatabase
        val values = ContentValues()
        values.put(Name, actors.Name)
        values.put(Age, actors.Age)
        values.put(Heigth,actors.heigth)
        values.put(City, actors.city)
        values.put(b_date, actors.bdate)
        values.put(b_city, actors.bcity)
        values.put(Education, actors.education)

        var success=po.insert(TABLE_NAME,null,values)
        po.close()
        return (Integer.parseInt("$success")!=-1)

    }

    @SuppressLint("Range")
    fun getAllActorsList():ArrayList<Actors>{

        val list =ArrayList<Actors>()
        val p0=readableDatabase
        var selectAll = "SELECT * FROM $TABLE_NAME"
        var cursor = p0.rawQuery(selectAll,null)

        if (cursor!=null){

            if (cursor.moveToFirst()){
                do{
                    val id = cursor.getString(cursor.getColumnIndex(ID))
                    val name = cursor.getString(cursor.getColumnIndex(Name))
                    val age = cursor.getString(cursor.getColumnIndex(Age))
                    val height = cursor.getString(cursor.getColumnIndex(Heigth))
                    val city = cursor.getString(cursor.getColumnIndex(City))
                    val bdate = cursor.getString(cursor.getColumnIndex(b_date))
                    val bcity = cursor.getString(cursor.getColumnIndex(b_city))
                    val education = cursor.getString(cursor.getColumnIndex(Education))

                    list.add(Actors(id.toInt(),name,age,height,city,bdate,bcity,education))
                }
                    while (cursor.moveToNext())
            }
        }
        cursor.close()
        p0.close()
        return list
    }
    override fun onUpgrade(p0: SQLiteDatabase?, p1: Int, p2: Int) {
        TODO("Not yet implemented")
    }

activity_second.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SecondActivity"
    android:orientation="vertical">

        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="v">

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_id"
        tools:ignore="Autofill,LabelFor,TextFields"
         />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_name"
        tools:ignore="Autofill,LabelFor,TextFields" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_age"


        />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_heigth"
       />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_city"/>

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_b_day"
        />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_b_city"/>

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/edit_education"/>


    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/add"
        android:text="btn_add"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/show"
        android:text="btn_show"/>

    <androidx.recyclerview.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/rec"/>



</LinearLayout>

Recycler_item.xml

    android:layout_width="wrap_content"
    android:layout_height="wrap_content"




    xmlns:android="http://schemas.android.com/apk/res/android">

<androidx.cardview.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/id"
        android:layout_marginLeft="4dp"
        android:textSize="20sp"/>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/name"
        android:textColor="@color/black"
        android:textSize="20sp"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="4dp"
        android:padding="20dp"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/height"
        android:textSize="18sp"
        android:paddingLeft="20dp"
        android:layout_marginLeft="10dp"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/age"
        android:textSize="18sp"
        android:paddingLeft="20dp"
        android:layout_marginLeft="10dp"/>





    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/city"
        android:layout_marginLeft="4dp"
        android:textSize="20sp"/>
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/b_date"
        android:textColor="@color/black"
        android:textSize="20sp"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="4dp"
        android:padding="20dp"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/b_city"
        android:textSize="18sp"
        android:paddingLeft="20dp"
        android:layout_marginLeft="10dp"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/education"
        android:textSize="18sp"

        android:paddingLeft="20dp"
        android:layout_marginLeft="10dp"/>
    </LinearLayout>

</androidx.cardview.widget.CardView>


</RelativeLayout>

Answer 1

点击“添加”按钮保存您的数据。试试这个方法。

btn_add.setOnClickListener {
      val actors = Actors()
      actors.Name = edit_name.text.toString()
      actors.Age = edit_age.text.toString()
      actors.heigth = edit_heigth.text.toString()
      actors.city = edit_city.text.toString()
      actors.bdate = edit_b_day.text.toString()
      actors.bcity = edit_b_city.text.toString()
      actors.education = edit_education.text.toString()

      var success = false
      success = dbHandle!!.addActors(actors)
      Toast.makeText(this, "result: $success", Toast.LENGTH_SHORT).show()
    }

我的应用程序显示 RecyclerView 但现在显示它的项目

my app shows RecyclerView but does now show it's items

android-recyclerview