Fill ComboBox with data from a table

Vaadin 6 / 7 / 8
1

I am using javaEE with wildfly and Vaadin 8.

In the Backend I have the following 2 entities:

@Entity
@Table(name = "ACCOUNT")
public class Account implements Serializable {

	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private int id;

	private String username;

	@NotNull
	private String password;

	@ManyToOne(fetch = FetchType.LAZY)
	@JoinColumn(name = "ACCOUNTGROUP_ID")
	private AccountGroup accountGroup;

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public AccountGroup getAccountGroup() {
		return this.accountGroup;
	}

	public void setAccountGroup(final AccountGroup accountGroup) {
		this.accountGroup = accountGroup;
	}
}

@Entity
@Table(name = "ACCOUNTGROUP")
public class AccountGroup implements Serializable {
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private int id;

	@NotNull
	private String name;
	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

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

In the Frontend I want now show/edit the Account by a Grid with a ComboBox.

@CDIView(MainView.ACCOUNT_VIEW)
public class AccountView extends VerticalLayout implements View {

	@Inject
	AccountService service;

	@Inject
	AccountGroupService acountGroupService;

	private Account entry;
	private Set<Account> selected;
	private Account selectedEntry;
	private TextField txfUsername = new TextField();
	private TextField txfPassword = new TextField();
	private ComboBox <AccountGroup>cbxAccountGroup = new ComboBox<>();

	public AccountView() {
		setSizeFull();
		setSpacing(true);
		addComponent(new TopMainMenu());
		addComponent(new Label("Account View"));
	}

	@Override
	public void enter(ViewChangeEvent event) {
		Notification.show("Showing view: Account View");
	}

	@PostConstruct
	void init() {
		selected = new HashSet<>();
		List<Account> list = service.getAllAccount();
		DataProvider<Account, ?> dataProvider = DataProvider.ofCollection(list);
		Grid<Account> grid = new Grid<Account>();
		grid.setSelectionMode(SelectionMode.MULTI);
		grid.addSelectionListener(event -> {
			selected = event.getAllSelectedItems();
		});

		grid.getEditor().setEnabled(true);
		grid.getEditor().addSaveListener(event -> {
			entry = event.getBean();
			updateRow(service, entry, grid);
		});

		cbxAccountGroup.setItems(acountGroupService.getAllAccountGroup());
		
		grid.setDataProvider(dataProvider);
		grid.addColumn(Account::getUsername).setCaption("Users Name").setEditorComponent(txfUsername,
				Account::setUsername);
		grid.addColumn(Account::getPassword).setCaption("Password").setEditorComponent(txfPassword,
				Account::setPassword);
		grid.addColumn(Account::getAccountGroup).setCaption("Account Group").setEditorComponent(cbxAccountGroup,
				Account::setAccountGroup);

		addComponent(grid);
	}

	private void updateRow(AccountService service, Account entry, Grid<Account> grid) {
		service.update(entry);
		refreshGrid(grid, service);
	}

	private void refreshGrid(Grid<Account> grid, AccountService service) {
		List<Account> list = service.getAllAccount();
		grid.setItems(list);
	}
}

Can you please give me some advice how to show the name of AccountGroup in the ComboBox cbxAccountGroup of the Grid?

2

If you simply want to change the captions of the items in the ComboBox, you can use [setItemCaptionGenerator]
(https://vaadin.com/download/release/8.4/8.4.1/docs/api/com/vaadin/ui/ComboBox.html#setItemCaptionGenerator-com.vaadin.ui.ItemCaptionGenerator-).

3

Thanks, now i have solved a part of the problem.
I use the following code:

@CDIView(MainView.PERSON_VIEW)
public class PersonView extends VerticalLayout implements View {

	@Inject
	NaturalPersonService service;

	@Inject
	TitleService titleService;

	private NaturalPerson entry;
	private Set<NaturalPerson> selected;
	private NaturalPerson selectedEntry;
	private TextField txfFirstName = new TextField();
	private TextField txfLastName = new TextField();
	private TextField txfComment = new TextField();
	private ComboBox<Title> cbxTitle = new ComboBox<>();

	public PersonView() {
		setSizeFull();
		setSpacing(true);
		addComponent(new TopMainMenu());
		addComponent(headingLabel());
}

	@PostConstruct
	void init() {
		selected = new HashSet<>();
		List<NaturalPerson> list = service.getAllNaturalPerson();
		list.sort(Comparator.comparing(NaturalPerson::getLastName));
		
		List<Title> titleList = titleService.getAllTitle();
		titleList.sort(Comparator.comparing(Title::getListPrio));

		DataProvider<NaturalPerson, ?> dataProvider = DataProvider.ofCollection(list);
		Grid<NaturalPerson> grid = new Grid<NaturalPerson>();
		grid.setSelectionMode(SelectionMode.MULTI);
		grid.addSelectionListener(event -> {
			selected = event.getAllSelectedItems();
		});

		grid.getEditor().setEnabled(true);
		grid.getEditor().addSaveListener(event -> {
			entry = event.getBean();
			updateRow(service, entry, grid);
		});

		cbxTitle.setPageLength(8);
		cbxTitle.setEmptySelectionAllowed(true);
		cbxTitle.setItemCaptionGenerator(Title::getTitle);
		cbxTitle.setItems(titleList);

		grid.setDataProvider(dataProvider);
		grid.addColumn(NaturalPerson::getFirstName).setCaption("First Name").setEditorComponent(txfFirstName,
				NaturalPerson::setFirstName);
		grid.addColumn(NaturalPerson::getLastName).setCaption("Last Name").setEditorComponent(txfLastName,
				NaturalPerson::setLastName);
		grid.addColumn(NaturalPerson::getTitle).setCaption("Titel").setEditorComponent(cbxTitle,
				NaturalPerson::setTitle);
		grid.addColumn(NaturalPerson::getComment).setCaption("Comment").setEditorComponent(txfComment,
				NaturalPerson::setComment);

		Button add = new Button("+");
		add.addClickListener(event -> addRow(service, grid));

		Button delete = new Button("-");
		delete.addClickListener(event -> deleteRow(service, selected, grid));

		Button details = new Button("details");
		details.addClickListener(event -> showDetails(service, selected, grid));

		HorizontalLayout tb = new HorizontalLayout(add, delete, details);
		addComponent(grid);
		addComponent(tb);
	}
.....

When i select now an Entry in the ComboBox “cbxTitle”, the values are shown correct.

But in the grid, i see something like this:

org.app.entity.Title@1eb77c155

How can i change this?

4

In this line of your code:

		grid.addColumn(NaturalPerson::getTitle).setCaption("Titel").setEditorComponent(cbxTitle,
				NaturalPerson::setTitle);

If you want to preserve NaturalPerson::getTitle as the column model, you can use one of the [setRenderer]
(https://vaadin.com/download/release/8.4/8.4.1/docs/api/com/vaadin/ui/Grid.Column.html#setRenderer-com.vaadin.ui.renderers.Renderer-) methods. The method with the presentationProvider also states its purpose in the API documentation as follows:

“The presentation provider is a method that takes the value of this column on a single row, and maps that to a value that the renderer accepts. This feature can be used for storing a complex value in a column for editing, but providing a simplified presentation for the user when not editing.”

So you could use that in conjunction with new TextRenderer() to display the field of org.app.entity.Title you want.

5

Thanks
how can i implement then the code with:

grid.addColumn(NaturalPerson::getTitle).setCaption("Titel").setEditorComponent(cbxTitle,
				NaturalPerson::setTitle).setRenderer(renderer);

can you give me please some more advise?

6

I think what you are looking for is:

import com.vaadin.ui.renderers.TextRenderer;
		
		...

		grid.addColumn(NaturalPerson::getTitle)
		    .setCaption("Title")
			.setRenderer(Title::getTitle, new TextRenderer())
		    .setEditorComponent(cbxTitle, NaturalPerson::setTitle);
7

a lot of thanks.
Now it works!!!

8

Sorry when i come back:
but i get now the following error:

13:49:18,436 SEVERE [com.vaadin.server.DefaultErrorHandler]
 (default task-9) : java.lang.NullPointerException
	at com.vaadin.ui.Grid$Column.generateRendererValue(Grid.java:1042)
	at com.vaadin.ui.Grid$Column.access$1100(Grid.java:831)
	at com.vaadin.ui.Grid$Column$1.generateData(Grid.java:862)
	at com.vaadin.data.provider.DataCommunicator.getDataObject(DataCommunicator.java:449)
	at com.vaadin.data.provider.DataCommunicator.pushData(DataCommunicator.java:429)
	at com.vaadin.data.provider.DataCommunicator.sendDataToClient(DataCommunicator.java:342)
	at com.vaadin.data.provider.DataCommunicator.beforeClientResponse(DataCommunicator.java:311)
	at com.vaadin.server.communication.UidlWriter.write(UidlWriter.java:126)
	at com.vaadin.server.communication.UIInitHandler.getInitialUidl(UIInitHandler.java:293)
	at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:82)
	at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:40)
	at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1601)
	at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:445)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
	at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
	at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
	at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
	at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
	at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
	at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
	at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
	at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
	at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
	at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
	at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
	at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
	at org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
	at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
	at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
	at io.undertow.server.Connectors.executeRootHandler(Connectors.java:326)
	at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:812)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

13:49:20,733 SEVERE [com.vaadin.server.DefaultErrorHandler]
 (default task-11) : java.lang.NullPointerException
	at com.vaadin.ui.Grid$Column.generateRendererValue(Grid.java:1042)
	at com.vaadin.ui.Grid$Column.access$1100(Grid.java:831)
	at com.vaadin.ui.Grid$Column$1.generateData(Grid.java:862)
	at com.vaadin.data.provider.DataCommunicator.getDataObject(DataCommunicator.java:449)
	at com.vaadin.data.provider.DataCommunicator.pushData(DataCommunicator.java:429)
	at com.vaadin.data.provider.DataCommunicator.sendDataToClient(DataCommunicator.java:342)
	at com.vaadin.data.provider.DataCommunicator.beforeClientResponse(DataCommunicator.java:311)
	at com.vaadin.server.communication.UidlWriter.write(UidlWriter.java:126)
	at com.vaadin.server.communication.UidlRequestHandler.writeUidl(UidlRequestHandler.java:124)
	at com.vaadin.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:92)
	at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:40)
	at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1601)
	at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:445)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
	at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
	at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
	at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
	at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
	at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
	at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
	at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
	at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
	at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
	at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
	at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
	at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
	at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
	at org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
	at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
	at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
	at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
	at io.undertow.server.Connectors.executeRootHandler(Connectors.java:326)
	at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:812)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

My Code is:

		cbxTitle.setPageLength(8);
		cbxTitle.setEmptySelectionAllowed(true);
		cbxTitle.setItemCaptionGenerator(Title::getTitleValue);
		cbxTitle.setItems(titleList);

		grid.setDataProvider(dataProvider);
		grid.addColumn(NaturalPerson::getFirstName).setCaption("First Name").setEditorComponent(txfFirstName,
				NaturalPerson::setFirstName);
		grid.addColumn(NaturalPerson::getLastName).setCaption("Last Name").setEditorComponent(txfLastName,
				NaturalPerson::setLastName);
		grid.addColumn(NaturalPerson::getTitle).setCaption("Title").setRenderer(Title::getTitleValue, new TextRenderer())
				.setEditorComponent(cbxTitle, NaturalPerson::setTitle);
9

If NaturalPerson::getTitle can be null you will need to implement a null-check for the renderer’s presentation provider.

For example:

.setRenderer(title -> title != null ? title.getTitleValue() : null, new TextRenderer())