Monday, 8 August 2016

LoadMore RecyclerView with progress bar showing at bottom


I am trying to get Endless Recycler View with progress bar showing at bottom when you are loading data from web service. But faced different problems.
Finally found a solution at this link. May be someone needs this.




build.gradle
---------------------
compile 'com.android.support:recyclerview-v7:24.0.0'
compile 'com.android.support:cardview-v7:24.0.0'

activity_main.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"
   
android:orientation="vertical"
   
app:layout_behavior="@string/appbar_scrolling_view_behavior"
   
tools:context="sgp.anil.com.firebaseexample.MainActivity"
   
tools:showIn="@layout/activity_main">

    <
android.support.v7.widget.RecyclerView
       
android:id="@+id/my_recycler_view"
       
android:layout_width="match_parent"
       
android:layout_height="wrap_content"
       
android:scrollbars="vertical" />

    <
TextView
       
android:id="@+id/empty_view"
       
android:layout_width="match_parent"
       
android:layout_height="match_parent"
       
android:gravity="center"
       
android:text="No Records"
       
android:visibility="gone" />
</
LinearLayout>
 list_row.xml
-----------------------
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView 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"
   
android:orientation="horizontal"
   
card_view:cardCornerRadius="5dp"
   
card_view:cardUseCompatPadding="true">

    <
RelativeLayout
       
android:layout_width="match_parent"
       
android:layout_height="match_parent"
       
android:background="?android:selectableItemBackground">

        <
TextView
           
android:id="@+id/tvName"
           
android:layout_width="match_parent"
           
android:layout_height="wrap_content"
           
android:layout_margin="5dp"
           
android:text="Name"
           
android:textColor="@android:color/black"
           
android:textSize="18sp" />

        <
TextView
           
android:id="@+id/tvEmailId"
           
android:layout_width="match_parent"
           
android:layout_height="wrap_content"
           
android:layout_below="@+id/tvName"
           
android:layout_margin="5dp"
           
android:text="Email Id"
           
android:textColor="@android:color/black"
           
android:textSize="12sp" />
    </
RelativeLayout>

</
android.support.v7.widget.CardView>
 progressbar.xml
-------------------------
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   
android:layout_width="match_parent"
   
android:layout_height="match_parent"
   
android:orientation="vertical" >

    <
ProgressBar
       
android:id="@+id/progressBar1"
       
android:layout_width="wrap_content"
       
android:layout_gravity="center_horizontal"
       
android:layout_height="wrap_content" />

</
LinearLayout>
 Student.Java
-------------------------
package sgp.anil.com.loadmore.utils;

import java.io.Serializable;

/**
 * Created by Anil on 05-08-2016.
 */
public class Student implements Serializable {

   
private static final long serialVersionUID = 1L;

   
private String name;

    
private String emailId;

   
public Student() {

    }

   
public Student(String name, String emailId) {
       
this.name = name;
       
this.emailId = emailId;
    }

   
public String getName() {
       
return name;
    }

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

   
public String getEmailId() {
       
return emailId;
    }

   
public void setEmailId(String emailId) {
       
this.emailId = emailId;
    }
}
 OnLoadMoreListener.Java
--------------------------------
package sgp.anil.com.loadmore.utils;

/**
 * Created by Anil on 05-08-2016.
*/

public interface OnLoadMoreListener {

    void onLoadMore();
}

DataAdapter.Java
-------------------------
package sgp.anil.com.loadmore.adapters;

import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import java.util.List;

import sgp.anil.com.loadmore.R;
import sgp.anil.com.loadmore.utils.OnLoadMoreListener;
import sgp.anil.com.loadmore.utils.Student;

/**
 * Created by Anil on 05-08-2016.
 */
public class DataAdapter extends RecyclerView.Adapter {
   
private final int VIEW_ITEM = 1;
   
private final int VIEW_PROG = 0;

   
private List<Student> studentList;

   
// The minimum amount of items to have below your current scroll position
    // before loading more.
   
private int visibleThreshold = 5;
   
private int lastVisibleItem, totalItemCount;
   
private boolean loading;
   
private OnLoadMoreListener onLoadMoreListener;


   
public DataAdapter(List<Student> students, RecyclerView recyclerView) {
       
studentList = students;

       
if (recyclerView.getLayoutManager() instanceof LinearLayoutManager) {

           
final LinearLayoutManager linearLayoutManager = (LinearLayoutManager) recyclerView
                    .getLayoutManager();


            recyclerView
                    .addOnScrollListener(
new RecyclerView.OnScrollListener() {
                       
@Override
                       
public void onScrolled(RecyclerView recyclerView,
                                              
int dx, int dy) {
                           
super.onScrolled(recyclerView, dx, dy);

                           
totalItemCount = linearLayoutManager.getItemCount();
                            
lastVisibleItem = linearLayoutManager
                                   
.findLastVisibleItemPosition();
                           
if (!loading
                                   
&& totalItemCount <= (lastVisibleItem + visibleThreshold)) {
                                
// End has been reached
                                // Do something
                               
if (onLoadMoreListener != null) {
                                   
onLoadMoreListener.onLoadMore();
                                }
                               
loading = true;
                            }
                        }
                    });
        }
    }

   
@Override
   
public int getItemViewType(int position) {
       
return studentList.get(position) != null ? VIEW_ITEM : VIEW_PROG;
    }

   
@Override
   
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent,
                                                     
int viewType) {
        RecyclerView.ViewHolder vh;
       
if (viewType == VIEW_ITEM) {
            View v = LayoutInflater.from(parent.getContext()).inflate(
                    R.layout.
list_row, parent, false);

            vh =
new StudentViewHolder(v);
        }
else {
            View v = LayoutInflater.from(parent.getContext()).inflate(
                    R.layout.
progressbar_item, parent, false);

            vh =
new ProgressViewHolder(v);
        }
       
return vh;
    }

   
@Override
   
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
       
if (holder instanceof StudentViewHolder) {

            Student singleStudent = (Student)
studentList.get(position);

            ((StudentViewHolder) holder).
tvName.setText(singleStudent.getName());

            ((StudentViewHolder) holder).
tvEmailId.setText(singleStudent.getEmailId());

            ((StudentViewHolder) holder).
student = singleStudent;

        }
else {
            ((ProgressViewHolder) holder).
progressBar.setIndeterminate(true);
        }
    }

   
public void setLoaded() {
       
loading = false;
    }

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

   
public void setOnLoadMoreListener(OnLoadMoreListener onLoadMoreListener) {
       
this.onLoadMoreListener = onLoadMoreListener;
    }


   
//
   
public static class StudentViewHolder extends RecyclerView.ViewHolder {
       
public TextView tvName;

       
public TextView tvEmailId;

       
public Student student;

       
public StudentViewHolder(View v) {
           
super(v);
           
tvName = (TextView) v.findViewById(R.id.tvName);

           
tvEmailId = (TextView) v.findViewById(R.id.tvEmailId);

            v.setOnClickListener(
new View.OnClickListener() {

               
@Override
               
public void onClick(View v) {
                    Toast.makeText(v.getContext(),
                           
"OnClick :" + student.getName() + " \n " + student.getEmailId(),
                            Toast.
LENGTH_SHORT).show();

                }
            });
        }
    }

   
public static class ProgressViewHolder extends RecyclerView.ViewHolder {
       
public ProgressBar progressBar;

       
public ProgressViewHolder(View v) {
           
super(v);
           
progressBar = (ProgressBar) v.findViewById(R.id.progressBar1);
        }
    }
}
 MainActivity.Java
--------------------------
package sgp.anil.com.loadmore;

import android.os.Bundle;
import android.os.Handler;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.TextView;

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

import sgp.anil.com.firebaseexample.adapters.DataAdapter;
import sgp.anil.com.firebaseexample.utils.OnLoadMoreListener;
import sgp.anil.com.firebaseexample.utils.Student;

public class MainActivity extends AppCompatActivity {

   
private TextView tvEmptyView;
   
private RecyclerView mRecyclerView;
   
private DataAdapter mAdapter;
   
private LinearLayoutManager mLayoutManager;

   
private List<Student> studentList;
   
   
protected Handler handler;

   
@Override
   
protected void onCreate(Bundle savedInstanceState) {
       
super.onCreate(savedInstanceState);
        setContentView(R.layout.
activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.
toolbar);
        setSupportActionBar(toolbar);

      
tvEmptyView = (TextView) findViewById(R.id.empty_view);
       
mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);
       
studentList = new ArrayList<Student>();
       
handler = new Handler();
       
if (toolbar != null) {
            setSupportActionBar(toolbar);
            getSupportActionBar().setTitle(
"SGP Students");

        }
        loadData();

       
// use this setting to improve performance if you know that changes
        // in content do not change the layout size of the RecyclerView
       
mRecyclerView.setHasFixedSize(true);

       
mLayoutManager = new LinearLayoutManager(this);

       
// use a linear layout manager
       
mRecyclerView.setLayoutManager(mLayoutManager);

       
// create an Object for Adapter
       
mAdapter = new DataAdapter(studentList, mRecyclerView);

       
// set the adapter object to the Recyclerview
       
mRecyclerView.setAdapter(mAdapter);
        
//  mAdapter.notifyDataSetChanged();


       
if (studentList.isEmpty()) {
           
mRecyclerView.setVisibility(View.GONE);
           
tvEmptyView.setVisibility(View.VISIBLE);

        }
else {
           
mRecyclerView.setVisibility(View.VISIBLE);
           
tvEmptyView.setVisibility(View.GONE);
        }

       
mAdapter.setOnLoadMoreListener(new OnLoadMoreListener() {
           
@Override
           
public void onLoadMore() {
               
//add null , so the adapter will check view_type and show progress bar at bottom
               
studentList.add(null);
               
mAdapter.notifyItemInserted(studentList.size() - 1);

               
handler.postDelayed(new Runnable() {
                   
@Override
                   
public void run() {
                       
//   remove progress item
                       
studentList.remove(studentList.size() - 1);
                       
mAdapter.notifyItemRemoved(studentList.size());
                       
//add items one by one
                        
int start = studentList.size();
                       
int end = start + 20;

                       
for (int i = start + 1; i <= end; i++) {
                           
studentList.add(new Student("Student " + i, "AndroidStudent" + i + "@gmail.com"));
                           
mAdapter.notifyItemInserted(studentList.size());
                        }
                       
mAdapter.setLoaded();
                       
//or you can add all at once but do not forget to call mAdapter.notifyDataSetChanged();
                   
}
                },
2000);

            }
        });

    }


   
// load initial data
   
private void loadData() {

       
for (int i = 1; i <= 20; i++) {
           
studentList.add(new Student("Student " + i, "androidstudent" + i + "@gmail.com"));

        }


    }

}



3 comments:

  1. please can you mail me the source code danito2060@gmail.com

    ReplyDelete
  2. Did the same thing, and paginated the response, but after each response, the progress bar sticks to the bottom of the last loaded page and the second list loads. here is a link to the git repo, please help

    https://github.com/davidshare/GithubDevelopersApp

    ReplyDelete