意图在 Recycleview.onclicklistener 中不起作用

Question

[this is the error image ][1]

Logates

This is my Adapter class i need to click the Recycleview list and go to the next page but Intend is not work in this class the app gets crashed how do i work with the intend in this ...

package com.onebook.locationsaver;

import android.app.Activity;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.provider.ContactsContract;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import androidx.recyclerview.widget.RecyclerView.ViewHolder;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;


import static android.content.ContentValues.TAG;
import static androidx.core.content.ContextCompat.startActivity;


public class SaveListAdapter extends androidx.recyclerview.widget.RecyclerView.Adapter<SaveListAdapter.ViewHolder>  {
Context context;
    public List<DatabseMode> databasemodelist;
    private DatabseMode databseMode;
    ArrayList<DatabseMode> newlist =new ArrayList<>();
    Context a;



    public SaveListAdapter(Context context, List<DatabseMode> databasemodelist) {

        this.databasemodelist=databasemodelist;


        for (int i = databasemodelist.size() - 1; i >= 0; i--) {
            newlist.add(databasemodelist.get(i));
            this.a=context;
        }
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
        View listItem= layoutInflater.inflate(R.layout.recycle_view_icon, parent, false);
        ViewHolder VH=new ViewHolder(context,listItem) {
            @Override
            public String toString() {
                return super.toString();
            }
        };
        return VH;

    }


    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {


        databseMode= (newlist.get(position));

        holder.name.setText(databseMode.getname());
        holder.detail.setText(databseMode.getdetail());

        /*holder.layout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(SaveListAdapter.this,"Item is selected",Toast.LENGTH_LONG).show();
*//*
                Intent intent=new Intent(a.getApplicationContext(),LocationEdit.class);
                intent.putExtra("potition",getItemId(position ));
                a.startActivity(intent);*//*

            }
        });*/
    }



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


    public static class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        public TextView name,detail;
        public LinearLayout layout;
        private Context context;
        List<DatabseMode> databasemodelist;

        public ViewHolder(Context context,View itemView) {
            super(itemView);
            this.name = (TextView) itemView.findViewById(R.id.textView);
            this.detail=itemView.findViewById(R.id.textview00);
            this.context=context;
            itemView.setOnClickListener(this);
            //layout= (LinearLayout) itemView;
        }



        @Override
        public void onClick(View v) {
            int position=getLayoutPosition();
            DatabseMode databseMode=databasemodelist.get(position);
            Intent intent=new Intent(context,LocationEdit.class);
            intent.putExtra("id",databseMode.getname());
            context.startActivity(intent);
            Toast.makeText(context,"this the text",Toast.LENGTH_SHORT).show();
        }
    }

}

The above is the adapter for recycleview

package com.onebook.locationsaver;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;
import java.util.List;

public class LocationList extends AppCompatActivity {

    private RecyclerView recyclerViewsavedata;
    private RecyclerView.Adapter getdataadapter;
    private List<DatabseMode> databasemodelist;
    private DatabaseHelper databaseHelper ;
    ListView listView;
    private Context context;


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



        databasemodelist =new ArrayList<>();
        databaseHelper =new DatabaseHelper(this);

        recyclerViewsavedata=findViewById(R.id.recyclerView);
        recyclerViewsavedata.setHasFixedSize(true);
        recyclerViewsavedata.setLayoutManager(new LinearLayoutManager(this));


        databasemodelist=databaseHelper.getAllCotacts();


        //listView.setAdapter(new Listviewadapter(LocationList.this,databasemodelist));
        getdataadapter=new SaveListAdapter((Activity) context,databasemodelist);
        recyclerViewsavedata.setAdapter(getdataadapter);
        recyclerViewsavedata.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Toast.makeText(LocationList.this,"This item is selecton",Toast.LENGTH_SHORT).show();
            }
        });
    }
}

The above is the Recycleview class ane one help me please i'm struggle on this for 4 days onclick in the recycle view is not working in my applilation

Answer 1

Change Your LocationList.class to this:

public class LocationList extends AppCompatActivity {

private RecyclerView recyclerViewsavedata;
private SaveListAdapter getdataadapter;
private List<DatabseMode> databasemodelist = new ArrayList<>();
private DatabaseHelper databaseHelper;


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

    recyclerViewsavedata = findViewById(R.id.recyclerView);
    recyclerViewsavedata.setHasFixedSize(true);
    recyclerViewsavedata.setLayoutManager(new LinearLayoutManager(this));

    databaseHelper = new DatabaseHelper(this);
    databasemodelist = databaseHelper.getAllCotacts();

    getdataadapter = new SaveListAdapter(LocationList.this, databasemodelist);
    recyclerViewsavedata.setAdapter(getdataadapter);
}}

Your SaveListAdapter.class to this:

public class SaveListAdapter extends androidx.recyclerview.widget.RecyclerView.Adapter<SaveListAdapter.ViewHolder>  {
private Context context;
private List<DatabseMode> databasemodelist;
private ArrayList<DatabseMode> newlist = new ArrayList<>();

public SaveListAdapter(Context context, List<DatabseMode> databasemodelist) {
    this.databasemodelist=databasemodelist;
    this.context = context;
    for (int i = databasemodelist.size() - 1; i >= 0; i--) {
        newlist.add(databasemodelist.get(i));
    }
}

@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
  return new SaveListAdapter.ViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.recycle_view_icon, parent, false));
}


@Override
public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {
    DatabseMode databseMode = newlist.get(position);
    holder.name.setText(databseMode.getname());
    holder.detail.setText(databseMode.getdetail());

    holder.itemView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Toast.makeText(context,"Item is selected",Toast.LENGTH_LONG).show();
            Intent intent=new Intent(context, LocationEdit.class);
            intent.putExtra("id",databseMode.getname());
            context.startActivity(intent);
        }
    });
}

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

public static class ViewHolder extends RecyclerView.ViewHolder {
    public TextView name;
    public TextView detail;

    public ViewHolder(Context context,View itemView) {
        super(itemView);
        name =  itemView.findViewById(R.id.textView);
        detail = itemView.findViewById(R.id.textview00);
    }
}}