如何将onClick监听器设置为recyclerView

Question

我想将onClick添加到recyclerView，以便将数据发送回表单"活动"以进行更新数据处理。当这段代码中没有适配器时，我如何实现onItemClickListner？

显示Employees.java:

package com.example.roomdatabaseandroid;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.ItemTouchHelper;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
import com.example.roomdatabaseandroid.DataModel.EmployeeDao;
import com.example.roomdatabaseandroid.DataModel.EmployeeDatabase;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
public class ShowEmployees extends AppCompatActivity {
private static final int EDIT_COURSE_REQUEST = 2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_employees);
RecyclerView recyclerView;
FloatingActionButton fab = findViewById(R.id.idFABAdd);
EmployeeDao employeeDao;
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//starting a new activity for adding a new course and passing a constant value in it.
Intent intent = new Intent(ShowEmployees.this, MainActivity.class);
startActivity(intent);
}
});
employeeDao = EmployeeDatabase.getDBInstance(this).employeeDao();
recyclerView = findViewById(R.id.employeeRecyclerView);
EmployeeRecycler employeeRecycler = new EmployeeRecycler(employeeDao.getAllEmployee());
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(employeeRecycler);
//below method is use to add swipe to delete method for item of recycler view.
new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
@Override
public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
return false;
}
@Override
public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
//on recycler view item swiped then we are deleting the item of our recycler view.
employeeDao.deleteEmployee(employeeRecycler.data.get(viewHolder.getAdapterPosition()));
Toast.makeText(ShowEmployees.this, "Employee deleted", Toast.LENGTH_SHORT).show();
}
}).attachToRecyclerView(recyclerView);
}
}

Employee_Recycler.java：

package com.example.roomdatabaseandroid;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

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

import com.example.roomdatabaseandroid.DataModel.DataConverter;
import com.example.roomdatabaseandroid.DataModel.Employee;

import java.util.List;

public class EmployeeRecycler extends RecyclerView.Adapter<EmployeeViewHolder> {

List<Employee> data;

public EmployeeRecycler(List<Employee> employees){
data = employees;
}

@NonNull
@Override
public EmployeeViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(
R.layout.list_item_1,
parent,false
);
return new EmployeeViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull EmployeeViewHolder holder, int position) {
Employee employee = data.get(position);
holder.imageView.setImageBitmap(DataConverter.convertByteArraytoImage(employee.getImage()));
holder.firstName.setText(employee.getFirstName());
holder.middleName.setText(employee.getMiddleName());
holder.lastName.setText(employee.getLastName());
holder.dob.setText(employee.getDOB());
holder.gender.setText(employee.getGender());
holder.address.setText(employee.getAddress());
holder.designation.setText(employee.getDesignation());
holder.email.setText(employee.getEmail());
holder.phoneNumber.setText(employee.getPhoneNumber());
}

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

}

EmployeeViewHolder.java:

package com.example.roomdatabaseandroid;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
public class EmployeeViewHolder extends RecyclerView.ViewHolder {
ImageView imageView;
TextView firstName,middleName,lastName,email,phoneNumber,address,designation,gender,dob;
public EmployeeViewHolder(@NonNull View itemView) {
super(itemView);
firstName = itemView.findViewById(R.id.idTVFirstName);
middleName = itemView.findViewById(R.id.idTVMiddleName);
lastName = itemView.findViewById(R.id.idTVLastName);
dob = itemView.findViewById(R.id.idTVDOB);
address = itemView.findViewById(R.id.idTVAddress);
gender = itemView.findViewById(R.id.idTVGender);
designation = itemView.findViewById(R.id.idTVDesignation);
email = itemView.findViewById(R.id.idTVEmail);
phoneNumber = itemView.findViewById(R.id.idTVPhoneNumber);
imageView = itemView.findViewById(R.id.profileImageView);
}
}

Answer 1

添加一个接口

interface AdapterItemClickListener {
void onItemClickListener(Employee employee, int position)
}

你的activity必须实现这个接口

public class ShowEmployees extends AppCompatActivity implements AdapterItemClickListener  {
private static final int EDIT_COURSE_REQUEST = 2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_show_employees);
RecyclerView recyclerView;
FloatingActionButton fab = findViewById(R.id.idFABAdd);
EmployeeDao employeeDao;
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//starting a new activity for adding a new course and passing a constant value in it.
Intent intent = new Intent(ShowEmployees.this, MainActivity.class);
startActivity(intent);
}
});
employeeDao = EmployeeDatabase.getDBInstance(this).employeeDao();
recyclerView = findViewById(R.id.employeeRecyclerView);
EmployeeRecycler employeeRecycler = new EmployeeRecycler(employeeDao.getAllEmployee(), this);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(employeeRecycler);


//below method is use to add swipe to delete method for item of recycler view.
new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
@Override
public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
return false;
}
@Override
public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
//on recycler view item swiped then we are deleting the item of our recycler view.
employeeDao.deleteEmployee(employeeRecycler.data.get(viewHolder.getAdapterPosition()));
Toast.makeText(ShowEmployees.this, "Employee deleted", Toast.LENGTH_SHORT).show();
}
}).attachToRecyclerView(recyclerView);
}
void onItemClickListener(Employee employee, int position) {
//update or another job
}
}

和您的适配器

public class EmployeeRecycler extends RecyclerView.Adapter<EmployeeViewHolder> {

List<Employee> data;
AdapterItemClickListener itemClickListener;

public EmployeeRecycler(List<Employee> employees, AdapterItemClickListener itemClickListener){
data = employees;
this.itemClickListener = itemClickListener;
}

@NonNull
@Override
public EmployeeViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(
R.layout.list_item_1,
parent,false
);
return new EmployeeViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull EmployeeViewHolder holder, int position) {
Employee employee = data.get(position);
holder.imageView.setImageBitmap(DataConverter.convertByteArraytoImage(employee.getImage()));
holder.firstName.setText(employee.getFirstName());
holder.middleName.setText(employee.getMiddleName());
holder.lastName.setText(employee.getLastName());
holder.dob.setText(employee.getDOB());
holder.gender.setText(employee.getGender());
holder.address.setText(employee.getAddress());
holder.designation.setText(employee.getDesignation());
holder.email.setText(employee.getEmail());
holder.phoneNumber.setText(employee.getPhoneNumber());

holder.itemView.setOnClickListener (v -> { 
itemClickListener.onItemClickListener(employee, position);
});
}

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

}