A Complete Example Integrating the Rating Star with Grid

package com.example.DemoProject;
import com.vaadin.server.ThemeResource;
public class Company {

    private int serialNo;
    private String name;
    private RatingStars rtstars;
    private ThemeResource rsrc;

    public Company() {
    }

    public Company(int serialNo, String name, RatingStars rtstars) {
        this.serialNo = serialNo;
        this.name = name;
        this.rtstars = rtstars;
    }

    public ThemeResource getRsrc() {
        return rsrc;
    }

    public void setRsrc(ThemeResource rsrc) {
        this.rsrc = rsrc;
    }

    public Company(int serialNo, String name, RatingStars rtstars, ThemeResource rsrc) {
        this.serialNo = serialNo;
        this.name = name;
        this.rtstars = rtstars;
        this.rsrc = rsrc;
    }

    public RatingStars getRtstars() {
        return rtstars;
    }

    public void setRtstars(RatingStars rtstars) {
        this.rtstars = rtstars;
    }

    public Company(int serialNo, String name) {
        this.serialNo = serialNo;
        this.name = name;
    }

    public int getSerialNo() {
        return serialNo;
    }

    public void setSerialNo(int serialNo) {
        this.serialNo = serialNo;
    }

    public String getName() {
        return name;
    }

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

}



AND THE UI 



package com.example.DemoProject;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;

import com.vaadin.annotations.PreserveOnRefresh;
import com.vaadin.data.provider.ListDataProvider;
import com.vaadin.navigator.View;
import com.vaadin.server.ThemeResource;
import com.vaadin.shared.ui.dnd.DropEffect;
import com.vaadin.shared.ui.dnd.EffectAllowed;
import com.vaadin.shared.ui.grid.DropMode;
import com.vaadin.ui.Button;
import com.vaadin.ui.Grid;
import com.vaadin.ui.Grid.Column;
import com.vaadin.ui.HorizontalLayout;
import com.vaadin.ui.TextField;
import com.vaadin.ui.components.grid.GridDragSource;
import com.vaadin.ui.components.grid.GridDropTarget;
import com.vaadin.ui.renderers.ImageRenderer;

@PreserveOnRefresh
public class CompanyRating extends HorizontalLayout implements View {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private ListDataProvider<Company> dataProvider;

    private List<Company> company;
    
    protected Grid<Company> grid = new Grid<>();

    private Optional<Company> dragged;

    public HorizontalLayout hlytbase = new HorizontalLayout();
    private Grid<Company> childgrid = new Grid<>();

    private ListDataProvider<Company> dp;
    TextField name = new TextField();

    TextField srno = new TextField();

    Button btn = new com.vaadin.ui.Button("ADD");


    private List<Company> items;
    public CompanyRating() {
        srno.setPlaceholder("enter Serial no");
        name.setPlaceholder("enter name");
        company = new ArrayList<>();
       
        company.add(new Company(1, "Dominoes", new RatingStars()));
        company.add(new Company(2, "Google", new RatingStars()));
        company.add(new Company(3, "Yahoo", new RatingStars()));
        company.add(new Company(4, "Ford", new RatingStars()));
        company.add(new Company(5, "Nissan", new RatingStars()));
        company.add(new Company(6, "BMW", new RatingStars()));
      
        dataProvider = new ListDataProvider<>(company);

        
        Map<Company, TextField> textFields = new HashMap<>();
        
        
        GridDragSource<Company> dragSource = new GridDragSource<>(grid);


        dragSource.setEffectAllowed(EffectAllowed.MOVE);

        dragSource.setDragDataGenerator("text", person -> {
            return person.getName() + " " + person.getSerialNo();
        });

        dragSource.addGridDragStartListener(event -> {
            List<Company> list = new ArrayList<>(event.getDraggedItems());
            if (!list.isEmpty()) {
                dragged = Optional.of(list.get(0));
            }
        });

        dragSource.addGridDragEndListener(event -> {
            if (event.getDropEffect() == DropEffect.MOVE) {
                grid.getDataProvider().refreshAll();
            }
        });
        
        GridDropTarget<Company> dropTarget = new GridDropTarget<>(grid, DropMode.ON_TOP);
        dropTarget.setDropEffect(DropEffect.MOVE);

        
        dropTarget.addGridDropListener(event -> {
            Optional<Company> dropTargetRow = event.getDropTargetRow();
            if (dropTargetRow.isPresent() && dragged.isPresent()) {
                Company drag = dragged.get();
                Company drop = dropTargetRow.get();
                Collections.swap(company, company.indexOf(drag), company.indexOf(drop));
                dataProvider.refreshAll();
            }
        });        
        

        grid.addColumn(Company::getSerialNo).setCaption("Serial Number").setWidth(50);
        grid.addColumn(Company::getName).setCaption("Name").setWidth(100);
        grid.addComponentColumn(Company::getRtstars).setCaption("Rate It");
        Column<Company, ThemeResource> imageColumn = grid.addColumn(
                p -> new ThemeResource(p.getName() + ".jpg"),
                        new ImageRenderer<Company>()).setCaption("Image");

       
        grid.setDataProvider(dataProvider);

        btn.addClickListener(e -> {
            if (!srno.getValue().isEmpty()) {
            company.add(new Company(Integer.parseInt(srno.getValue()), name.getValue(),
                    new RatingStars()));
            dataProvider.refreshAll();
            }
        });


        addComponents(srno, name, btn, grid);

        items = new ArrayList<>();
        dp = new ListDataProvider<>(items);
        childgrid.addColumn(Company::getSerialNo).setCaption("Number");
        childgrid.addColumn(Company::getName).setCaption("Company");
        childgrid.setDataProvider(dp);
        addComponent(childgrid);
        childgrid.setVisible(false);

        grid.addItemClickListener(e -> {
            items.clear();
            Company company = e.getItem();
            if (company != null) {
                childgrid.setVisible(true);
                items.add(company);
            } else {
                childgrid.setVisible(false);
            }
            dp.refreshAll();
        });

    }
}