Question

我正在使用“回收者视图”方法创建列表。但是，如果我插入数据。RecyclerView显示所有行，但最后插入的数据显示在所有先前行上。我在Sqlite数据库的所有行数据中检查了SQLite数据库中的数据是否正确/正确，但在RecyclerView中却发现了问题。

i用调试模式检查了所有数据。它们从SQLite数据库到Cursor都正确了；我将Coursor分配给List；在OtherClass中，数据从List中得到了正确的。但是从列表到Recyclerview不正确。

查看此输出   Please See The OUTPUT OfScreen on The Image Click on this Link

模型类：

公共类服务{

public  int  VehicleID;
public  String  VehicleMake;
public  String  VehicleModel;
public  String  VehicleReg;
public  String  CustomerName;
public  String  Contact;
public  String  ServiceType;
public  String  Amount;
public  String  Party;
public  String  Comments;



public int getVehicleID() {
    return VehicleID;
}

public void setVehicleID(int vehicleID) {
    VehicleID = vehicleID;
}

public String getVehicleMake() {
    return VehicleMake;
}

public void setVehicleMake(String vehicleMake) {
    VehicleMake = vehicleMake;
}

public String getVehicleModel() {
    return VehicleModel;
}

public void setVehicleModel(String vehicleModel) {
    VehicleModel = vehicleModel;
}

public String getVehicleReg() {
    return VehicleReg;
}

public void setVehicleReg(String vehicleReg) {
    VehicleReg = vehicleReg;
}

public String getCustomerName() {
    return CustomerName;
}

public void setCustomerName(String customerName) {
    CustomerName = customerName;
}

public String getContact() {
    return Contact;
}

public void setContact(String contact) {
    Contact = contact;
}

public String getServiceType() {
    return ServiceType;
}

public void setServiceType(String serviceType) {
    ServiceType = serviceType;
}

public String getAmount() {
    return Amount;
}

public void setAmount(String amount) {
    Amount = amount;
}

public String getParty() {
    return Party;
}

public void setParty(String party) {
    Party = party;
}

public String getComments() {
    return Comments;
}

public void setComments(String comments) {
    Comments = comments;
}
}

MngServices类： //从数据库中获取数据

public class MngServices extends SQLiteOpenHelper 
{

SQLiteDatabase db;

Services mServies = new Services(); //ModelClass
ArrayList<Services> lstmService;   //List
//Database Variables
public static final String DB_NAME = "CarWashDB.db";  //database file
public static final int DB_VERSION = 1;   
public static final String TABLE_NAME = "tblService";  ..tableName

public static final String VehicleID = "VehicleID";
public static final String VehicleMake = "VehicleMake";
public static final String VehicleModel = "VehicleModel";
public static final String VehicleReg = "VehicleReg";
public static final String CustomerName = "CustomerName";
public static final String Contact = "Contact";
public static final String ServiceType = "ServiceType";
public static final String Amount = "Amount";
public static final String Party = "Party";
public static final String Comments = "Comments";

//TODO Constructor
public MngServices(Context context) {
    super(context, DB_NAME, null, DB_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
           db.execSQL("create table " + TABLE_NAME + " ( " + VehicleID + " INTEGER PRIMARY KEY AUTOINCREMENT," + VehicleMake + " TEXT, " + VehicleModel + " TEXT, " + VehicleReg + " TEXT, " + CustomerName + " TEXT, " + Contact + " TEXT, " + ServiceType + " TEXT, " + Amount + " TEXT, " + Party + " TEXT, " + Comments + " TEXT);");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
    onCreate(db);
}

public boolean insertService(Services mS){

    db = this.getWritableDatabase();
    db.execSQL("INSERT INTO " + TABLE_NAME + "(" + VehicleMake + "," + VehicleModel + "," + VehicleReg + "," + CustomerName + "," + Contact + "," + ServiceType + "," + Amount + "," + Party + "," + Comments + ") VALUES('" + mS.getVehicleMake() + "','" + mS.getVehicleModel() + "','" + mS.getVehicleReg() + "','" + mS.getCustomerName() + "','" + mS.getContact() + "','" + mS.getServiceType() + "','" + mS.getAmount() + "','" + mS.getParty() + "','" + mS.getComments() + "')");
    db.close();

        if(db.toString() == "-1")
            return false;
        else
            return true;
}


public ArrayList <Services> getAllService(){
    lstmService = new ArrayList<Services>();
      db = this.getReadableDatabase();
 //   String selectQuery = String.format("Select VehicleMake,VehicleModel,VehicleReg,ServiceType,Amount,CustomerName from "+TABLE_NAME,null);
    Cursor c = db.rawQuery("Select "+VehicleMake+","+VehicleModel+","+VehicleReg+","+ServiceType+","+Amount+","+CustomerName+ " from " +TABLE_NAME,null);

     if(c.getCount() > 0){
     //  for (int i = 0; i < c.getCount(); i++) {
    while( c.moveToNext()){

     // mServies.setVehicleID(Integer.parseInt(c.getString((c.getColumnIndexOrThrow( "VehicleID")))));
         mServies.setVehicleMake(c.getString(c.getColumnIndexOrThrow("VehicleMake")));
         mServies.setVehicleModel(c.getString(c.getColumnIndexOrThrow("VehicleModel")));
         mServies.setVehicleReg(c.getString(c.getColumnIndexOrThrow("VehicleReg")));
         mServies.setServiceType(c.getString(c.getColumnIndex("ServiceType")));
         mServies.setAmount(c.getString(c.getColumnIndex("Amount")));
         mServies.setCustomerName(c.getString(5));
        // Log.d("ListError  ", String.valueOf( a +": "+ mServies.VehicleMake +" = "+ mServies.VehicleModel+" = "+mServies.VehicleReg+" = "+mServies.ServiceType+" = "+ mServies.Amount+" = "+mServies.CustomerName));
         lstmService.add(mServies);
       }
   }
    c.close();
    db.close();
    return lstmService;
}
}

ADPATER CLASS //用于RecyclreView绑定数据

//OuterClass   . InnerClass
 public class ServiceRAdapter extends 
 RecyclerView.Adapter<ServiceRAdapter.ServiceAdapterInnerClass>
 {

               Context context;
               ArrayList<Services> ArrLstService;

                //Outer Class Constructor
               public ServiceRAdapter(Context context, ArrayList<Services> data) {
                   this.context = context;
                   this.ArrLstService = data;
               }

               @NonNull
               @Override
               public ServiceAdapterInnerClass onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
                   View v = LayoutInflater.from(context).inflate(R.layout.service_list_row, viewGroup ,false);
                   return new ServiceAdapterInnerClass(v);
               }

               @Override
               public void onBindViewHolder(@NonNull ServiceAdapterInnerClass serviceAdapterInnerClass, int i) {
                //Inner Class Views & ModelList-Attr binding

                   serviceAdapterInnerClass.VehicleMake.setText(ArrLstService.get(i).getVehicleMake());
                   serviceAdapterInnerClass.VehicleModel.setText(ArrLstService.get(i).getVehicleModel());
                   serviceAdapterInnerClass.VehicleReg.setText(ArrLstService.get(i).getVehicleReg());
                   serviceAdapterInnerClass.CustomerName.setText(ArrLstService.get(i).getCustomerName());
                   serviceAdapterInnerClass.ServiceType.setText(ArrLstService.get(i).getServiceType());
                   serviceAdapterInnerClass.Amount.setText(ArrLstService.get(i).getAmount());
                   Log.d("getVehicleMake:", String.valueOf(ArrLstService.get(i).getVehicleMake()));
                   Log.d("getVehicleModel:", String.valueOf(ArrLstService.get(i).getVehicleModel()));
                   Log.d("getVehicleReg:", String.valueOf(ArrLstService.get(i).getVehicleReg()));
                   Log.d("getCustomerName:", String.valueOf(ArrLstService.get(i).getCustomerName()));
                   Log.d("getServiceType:", String.valueOf(ArrLstService.get(i).getServiceType()));
                   Log.d("getAmount:", String.valueOf(ArrLstService.get(i).getAmount()));

               }

               @Override
               public int getItemCount() {
                   return ArrLstService.size();
               }

               // -> Inner Class <-
  class ServiceAdapterInnerClass extends RecyclerView.ViewHolder {
   TextView VehicleMake,ServiceType,VehicleModel,VehicleReg,CustomerName,Amount;

     //Inner Class Constructor
    public ServiceAdapterInnerClass(@NonNull View itemView) {
        super(itemView);
         VehicleMake  = (TextView)itemView.findViewById(R.id.trVehicleMake);
         ServiceType= (TextView)itemView.findViewById(R.id.trServiceType);
         VehicleModel = (TextView)itemView.findViewById(R.id.trVehicleModel);
         VehicleReg = (TextView)itemView.findViewById(R.id.trVehicleReg);
         CustomerName = (TextView)itemView.findViewById(R.id.trCustomerName);
         Amount = (TextView)itemView.findViewById(R.id.trAmount);
    }
}//Inner Class
}//Outer Class

主类

public class ServicesList extends AppCompatActivity 
{

RecyclerView recyclerID;
ServiceRAdapter adapter;
ArrayList<Services> sList;

ListView lvListID; //Header-List_ID
ViewGroup headerview; //For Header
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_services_list);//Main List Layout


    headerRows();
    tableRows();
}

private void headerRows() {
    lvListID =(ListView) findViewById(R.id.lvListID);
    headerview = (ViewGroup)getLayoutInflater() .inflate(R.layout.header_services,lvListID,false);
    lvListID.addHeaderView(headerview); //Adding Header
}

private void tableRows() {

    MngServices objServices = new MngServices(this);
    recyclerID =(RecyclerView) findViewById(R.id.recyclerID);
    recyclerID.setHasFixedSize(true);
    recyclerID.setLayoutManager(new LinearLayoutManager(this));
    sList =objServices.getAllService();

    //---------------------------------------------//
    adapter = new ServiceRAdapter( ServicesList.this,sList);
    recyclerID.setAdapter(adapter);
}
}

Answer 1

在您的getAllService()方法中，您将为每个循环迭代重用相同的Services对象。为每一行实例化一个新对象，例如

while( c.moveToNext()){
    mServies = new Services();
    mServies.set...();
    lstmService.add(mServies);
}

Answer 2

尝试如下插入数据例如

public boolean insertData(String name,String surname,String marks) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues contentValues = new ContentValues();
        contentValues.put(COL_2,name);
        contentValues.put(COL_3,surname);
        contentValues.put(COL_4,marks);
        long result = db.insert(TABLE_NAME,null ,contentValues);
        if(result == -1)
            return false;
        else
            return true;
    }

在数据库中的getAllService（）下，首先将光标移至第一位置

public ArrayList <Services> getAllService(){
    lstmService = new ArrayList<Services>();
      db = this.getReadableDatabase();
 //   String selectQuery = String.format("Select VehicleMake,VehicleModel,VehicleReg,ServiceType,Amount,CustomerName from "+TABLE_NAME,null);
    Cursor c = db.rawQuery("select * from " +TABLE_NAME,null);

     if(c != null && c.getCount() > 0){
        c.moveToFrist()
        do{

        // mServies.setVehicleID(Integer.parseInt(c.getString((c.getColumnIndexOrThrow( "VehicleID")))));
         mServies.setVehicleMake(c.getString(c.getColumnIndexOrThrow("VehicleMake")));
         mServies.setVehicleModel(c.getString(c.getColumnIndexOrThrow("VehicleModel")));
         mServies.setVehicleReg(c.getString(c.getColumnIndexOrThrow("VehicleReg")));
         mServies.setServiceType(c.getString(c.getColumnIndex("ServiceType")));
         mServies.setAmount(c.getString(c.getColumnIndex("Amount")));
         mServies.setCustomerName(c.getString(5));
        // Log.d("ListError  ", String.valueOf( a +": "+ mServies.VehicleMake +" = "+ mServies.VehicleModel+" = "+mServies.VehicleReg+" = "+mServies.ServiceType+" = "+ mServies.Amount+" = "+mServies.CustomerName));
         lstmService.add(mServies);
        }while(c.moveToNext())
   }
    c.close();
    db.close();
    return lstmService;
}

如何修复Android RecyclerView显示所有先前行SqliteDatabase的最后一行数据

2 个答案: