Что не так с моим customAdapter или Activity.java?мой ListView не показывает его элемент при запуске приложения - PullRequest
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Что не так с моим customAdapter или Activity.java?мой ListView не показывает его элемент при запуске приложения

0 голосов
/ 29 января 2019

Я разрабатываю RecyclerView и использую CustomAdapter, и мое приложение работает нормально, но мой ListView не показывает его содержимое!что отсутствует или не так с моим кодом?Я попытался вернуть arraylist.size () и набрал list.setHasFixedSize, но ничего не получилось!

prospectowner_listview.java (класс активности) 

public class prospectowner_listview extends AppCompatActivity {

    RecyclerView list;
    ArrayList <com.example.android.e7gzlykora.owner> ownerlist = new ArrayList <>();
    private DatabaseReference mFirebaseDatabase;
    private FirebaseDatabase mFirebaseInstance;
    owner owner;
    customAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.prospectowner_listview);

        list = findViewById(R.id.list);
        LinearLayoutManager manager = new LinearLayoutManager(this);
        list.setLayoutManager(manager);
        list.setHasFixedSize(true);
        manager.setOrientation(LinearLayoutManager.VERTICAL);
        adapter = new customAdapter(prospectowner_listview.this,ownerlist);

        mFirebaseInstance = FirebaseDatabase.getInstance();
        mFirebaseDatabase = mFirebaseInstance.getReference("owners");

        mFirebaseDatabase.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                for (DataSnapshot data: dataSnapshot.getChildren()){
                    owner o = data.getValue(owner.class);
                    ownerlist.add(o);
                }
                list.setAdapter(adapter);
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) { }
        });
    }
}

CustomerAdapter.java 

public class customAdapter extends RecyclerView.Adapter<customAdapter.MyViewHolder>{

    private final ArrayList<owner> ownerlist;
    private final Context mContext;

    public customAdapter(Context c , ArrayList<owner> p) {
        this.mContext = c;
        this.ownerlist = new ArrayList <>();
    }

    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int 
    viewType) {
        return new MyViewHolder(LayoutInflater.from(mContext).inflate(R.layout.prospectowners,parent,false));
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        owner owner = ownerlist.get(position);

        holder.name.setText(owner.getName());
        holder.field.setText(owner.getFieldname());
        holder.mobile.setText(owner.getMobile());
        holder.address.setText(owner.getAddress());
        holder.cost.setText(owner.getCost());
    }

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

    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView name;
        public TextView field;
        public TextView mobile;
        public TextView address;
        public TextView cost;

       public MyViewHolder(View itemView) {
            super(itemView);
            this.name = itemView.findViewById(R.id.name);
            this.field =  itemView.findViewById(R.id.fieldName);
            this.mobile =  itemView.findViewById(R.id.mobileowner);
            this.address =  itemView.findViewById(R.id.address);
            this.cost =  itemView.findViewById(R.id.cost);
        }
    }
}

Owner.java 

public class owner extends ArrayList <owner> {

    public String name;
    public String mobile;
    public String fieldname;
    public String address;
    public String cost;
    public String zone1;
    public String zone2;
    private Class thisClass;

    public owner(){}

    public owner(String name, String mobile,String fieldname,String address, String cost, String zone1, String zone2) {
        this.name = name;
        this.mobile = mobile;
        this.fieldname = fieldname;
        this.address = address;
        this.cost = cost;
        this.zone1 = zone1;
        this.zone2 = zone2;
    }

    public String getMobile() {
        return mobile;
    }

    public String getName() {
        return name;
    }

     public String getAddress() {
        return address;
     }

    public void setName(String name) {
        this.name = name;
    }

    public void setMobile(String mobile) {
        this.mobile = mobile;
    }

    public void setFieldname(String fieldname) {
        this.fieldname = fieldname;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public void setCost(String cost) {
        this.cost = cost;
    }

    public void setZone1(String zone1) {
        this.zone1 = zone1;
    }

    public void setZone2(String zone2) {
        this.zone2 = zone2;
    }

    public void setThisClass(Class thisClass) {
        this.thisClass = thisClass;
    }

    public String getFieldname() {
        return fieldname;
    }

    public String getCost() {
        return cost;
    }

    public String getZone1() {
        return zone1;
    }

    public String getZone2() {
        return zone2;
    }

}

------------- prospectowners.xml--------------------------- 

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


    <TextView
        android:id="@+id/fieldName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text=""
        android:textColor="@android:color/black"
        android:textStyle="bold"
         />

    <TextView
        android:id="@+id/nameowner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/fieldName"
        android:layout_marginStart="50dp"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="10dp"
        android:text=""
        android:textColor="@android:color/black"
        />

    <TextView
        android:id="@+id/mobileowner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/nameowner"
        android:layout_marginStart="50dp"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="10dp"
        android:textColor="@android:color/black"
         />

    <TextView
        android:id="@+id/address"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/mobileowner"
        android:layout_marginStart="50dp"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="10dp"
        android:textColor="@android:color/black"
         />

    <TextView
        android:id="@+id/cost"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/address"
        android:layout_marginStart="50dp"
        android:layout_marginLeft="50dp"
        android:layout_marginTop="10dp"
        android:textColor="@android:color/black"
         />

    <Button
        android:id="@+id/reserve"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
            android:layout_below="@+id/cost"
        android:onClick="reserve"
            android:layout_marginStart="230dp"
            android:layout_marginLeft="270dp"
            android:layout_marginTop="10dp"
            android:text="E7gzly"
            android:textSize="15dp" />


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingBottom="@dimen/activity_vertical_margin">

    <android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/list"
    android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>

Ответы [ 4 ]

0 голосов
/ 01 февраля 2019

Список массивов всегда пуст, потому что в конструкторе адаптера вы инициализируете как новый список.Пожалуйста, проверьте это

enter image description here

0 голосов
/ 29 января 2019

Создание новой функции в вашем адаптере: 

public void addData(List<Owner> owners){
 this.ownerList = owners;
 notifyOnDataSetChanged();
}

и в onDataChange вызов: 

adapter.addData(owners);
0 голосов
/ 29 января 2019

Я думаю, что проблема связана с вашим адаптером, измените код адаптера, как показано ниже: 

public class customAdapter extends RecyclerView.Adapter<customAdapter.MyViewHolder>{

    private ArrayList<owner> ownerlist;
    private Context mContext;

    public customAdapter(Context c , ArrayList<owner> p) {
        this.mContext = c;
        this.ownerlist = p;
    }

    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int 
    viewType) {
        return new MyViewHolder(LayoutInflater.from(mContext).inflate(R.layout.prospectowners,parent,false));
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        owner owner = ownerlist.get(position);

        holder.name.setText(owner.getName());
        holder.field.setText(owner.getFieldname());
        holder.mobile.setText(owner.getMobile());
        holder.address.setText(owner.getAddress());
        holder.cost.setText(owner.getCost());
    }

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

    public void addData(ArrayList<owner> newData){
        this.ownerlist.addAll(newData);
        notifyOnDataSetChanged();
    }

    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView name;
        public TextView field;
        public TextView mobile;
        public TextView address;
        public TextView cost;

       public MyViewHolder(View itemView) {
            super(itemView);
            this.name = itemView.findViewById(R.id.name);
            this.field =  itemView.findViewById(R.id.fieldName);
            this.mobile =  itemView.findViewById(R.id.mobileowner);
            this.address =  itemView.findViewById(R.id.address);
            this.cost =  itemView.findViewById(R.id.cost);
        }
    }
}

, затем вызовите метод addData следующим образом: 

@Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                for (DataSnapshot data: dataSnapshot.getChildren()){
                    owner o = data.getValue(owner.class);
                    ownerlist.add(o);
                }
                list.setAdapter(adapter);
                adapter.addData(ownerlist);

            }

Кстати, на самом деле выможет установить адаптер вне слушателя

ОБНОВЛЕНИЕ (Это обновление устанавливает позицию значения адаптера по умолчанию для пустых данных, затем оно будет заполнено при срабатывании слушателя) 

public class customAdapter extends RecyclerView.Adapter<customAdapter.MyViewHolder>{

    private ArrayList<owner> ownerlist;
    private Context mContext;

    public customAdapter(Context c , ArrayList<owner> p) {
        this.mContext = c;
        this.ownerlist = new Arraylist<>();
    }

    @NonNull
    @Override
    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int 
    viewType) {
        return new MyViewHolder(LayoutInflater.from(mContext).inflate(R.layout.prospectowners,parent,false));
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        owner owner = ownerlist.get(position);

        holder.name.setText(owner.getName());
        holder.field.setText(owner.getFieldname());
        holder.mobile.setText(owner.getMobile());
        holder.address.setText(owner.getAddress());
        holder.cost.setText(owner.getCost());
    }

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

    public void addData(ArrayList<owner> newData){
        this.ownerlist.addAll(newData);
        notifyOnDataSetChanged();
    }

    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView name;
        public TextView field;
        public TextView mobile;
        public TextView address;
        public TextView cost;

       public MyViewHolder(View itemView) {
            super(itemView);
            this.name = itemView.findViewById(R.id.name);
            this.field =  itemView.findViewById(R.id.fieldName);
            this.mobile =  itemView.findViewById(R.id.mobileowner);
            this.address =  itemView.findViewById(R.id.address);
            this.cost =  itemView.findViewById(R.id.cost);
        }
    }
}

public class prospectowner_listview extends AppCompatActivity {

    RecyclerView list;
    ArrayList <com.example.android.e7gzlykora.owner> ownerlist = new ArrayList <>();
    private DatabaseReference mFirebaseDatabase;
    private FirebaseDatabase mFirebaseInstance;
    owner owner;
    customAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.prospectowner_listview);

        list = findViewById(R.id.list);
        LinearLayoutManager manager = new LinearLayoutManager(this);
        list.setLayoutManager(manager);
        list.setHasFixedSize(true);
        manager.setOrientation(LinearLayoutManager.VERTICAL);
        adapter = new customAdapter(prospectowner_listview.this,ownerlist);
        list.setAdapter(adapter);

        mFirebaseInstance = FirebaseDatabase.getInstance();
        mFirebaseDatabase = mFirebaseInstance.getReference("owners");

        mFirebaseDatabase.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                for (DataSnapshot data: dataSnapshot.getChildren()){
                    owner o = data.getValue(owner.class);
                    ownerlist.add(o);
                }
                adapter.addData(ownerlist);
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) { }
        });
    }
}
0 голосов
/ 29 января 2019

Попробуйте,

В вашем классе активности измените 

list.setAdapter(adapter)

на 

list.setAdapter(new customAdapter(prospectowner_listview.this, ownerlist));
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