Using List and Grid in Android -Recycleview

• The displacements  in List or Grid is Very common in Mobile Development, 
• the user can sea collection of list and scroll through them, 
• The collection of things can be list or Grid,
• to show elements like Grid type or list type we can Use Recycleview.

RecyclerView:

The RecyclerView widget is a more advanced and flexible version of ListView. This widget is a container for displaying large data sets that can be scrolled very efficiently by maintaining a limited number of views.

Using RecyclerView : 

• The recycle view supports the  display collection of Data
• it is a moderate version of Listview and Gridview from Android Framework.
• Recycleview Uses ViewHolder to store a reference of view for One entry.
• ViewHolder is static Inner class in Adapter it holds reference of Relevant Views 

Gradel Dependency for Recyclview:

   Add following dependency to gradle

compile "com.android.support:recyclerview-v7:26.1.0"

.

Adapters:

• Adapter manages the data model and adapts into the into the individual entry in the widge
• it extends RecyclerView.Adapter  

android Recyclview development step by Step:

step-1: (create list-item-view )

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout
    android:layout_margin="5dp"    android:layout_marginTop="5dp"    android:orientation="vertical"    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"    android:layout_height="wrap_content">
    <TextView       android:gravity="bottom"        android:text="Mahesh"        android:id="@+id/txt_Name"        android:textColor="@color/colorAccent"        android:layout_width="match_parent"        android:layout_height="50dp" />
    <TextView        android:gravity="center_vertical"        android:text="1234567891"        android:id="@+id/txt_number"        android:textColor="@color/colorPrimary"        android:layout_width="match_parent"        android:layout_height="50dp" />
</LinearLayout>

Step-2:(Create UserModel):

Create Model 

public class UserModel {
    public String _Name;
    public  String _Number;

    public UserModel(String _Name, String _Number) {
        this._Name = _Name;
        this._Number = _Number;
    }

    public String get_Name() {
        return _Name;
    }

    public void set_Name(String _Name) {
        this._Name = _Name;
    }

    public String get_Number() {
        return _Number;
    }

    public void set_Number(String _Number) {
        this._Number = _Number;
    }
}

Step-3 : (Create Adapter Class with View Holder)

Crate Adapter For class

public class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder> {
    ArrayList<UserModel> userData=new ArrayList<>();

    public Adapter(ArrayList<UserModel> userData) {
        this.userData = userData;
    }

    @Override    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());

        View v= inflater.inflate(R.layout.listitem_row,parent,false);
        ViewHolder holder=new ViewHolder(v);
        return holder;
    }

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

      /*  Get User Info Based On Position */        UserModel curentUser= userData.get(position);

        holder._txtName.setText(curentUser._Name);
        holder._txtNumber.setText(curentUser._Number);

    }

    @Override    public int getItemCount() {
        /*  Get Count from Data */                return userData.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder{

        public TextView _txtName;
        public TextView _txtNumber;

        public ViewHolder(View v) {
            super(v);
            _txtName= v.findViewById(R.id.txt_Name);
            _txtNumber= v.findViewById(R.id.txt_number);

        }
    }

}

step-4: (Add recyview in Main layout):

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:background="@color/colorPrimary"    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"    tools:context="in.arula.android_list.MainActivity">

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

    </android.support.v7.widget.RecyclerView>

</android.support.constraint.ConstraintLayout>

Step-5 (Write Code in Main-Activity):

public class MainActivity extends AppCompatActivity {

    ArrayList<UserModel> userData=new ArrayList<>();

    private RecyclerView recyclerView;
    private RecyclerView.Adapter mAdapter;
    private RecyclerView.LayoutManager layoutManager;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        /* Add data to User List */        Adddata();
        recyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);

        // use this setting to        // improve performance if you know that changes        // in content do not change the layout size        // of the RecyclerView
        recyclerView.setHasFixedSize(true);
        // use a linear layout manager        layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        mAdapter = new Adapter(userData);
        recyclerView.setAdapter(mAdapter);



    }

    private void Adddata() {

        userData.add(new UserModel("Mahesh","12345678"));
        userData.add(new UserModel("Suresh","1234567e87"));
        userData.add(new UserModel("Rahul","123456734287"));
        userData.add(new UserModel("Amith","12345884748"));
        userData.add(new UserModel("Sagar","12345378974"));
        userData.add(new UserModel("Mahesh","12345678"));
        userData.add(new UserModel("Suresh","1234567e87"));
        userData.add(new UserModel("Rahul","123456734287"));
        userData.add(new UserModel("Amith","12345884748"));
        userData.add(new UserModel("Sagar","12345378974"));


    }
}