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Best Vaadin component for a list of String

My issue is I have a simple List of Strings say
List<String> names = List.of("Frank","Joe","Eva");
All I want is display it on the UI. With some simple code like
ListComponent lc = new ListComponent.setItems(names);
I have tried it with Table which seems to work but code behind it is a bit boilerplate for this simple task(7-8 line of code).
I have tried also the Grid component and it works well when I want to bind a POJO to it , but with String.class type its a nightmare.
Grid<String> listGrid= new Grid<>(String.class) ;
listGrid.setItems(names);
it doesnt work because I have to provide getters for the column, which String.class doesnt have for the value. So I did this:
Grid<String> listGrid= new Grid<>(String.class) ;
listGrid.setItems(names);
listGrid.addColumn(String::toString).setCaption("name");
It works! However unspecified columns also appear in the grid, so now I have 3 columns Byte,Empty,name. And I dont know why. Where are these comes from?

What are the requirements for displaying them? Just to get them on the screen? Is Label enough?
for(String name: names) {
mylayout.addComponent(new Label(name))
}
If you need selection, then maybe ListSelect or ComboBox are the go-to’s.

If you want to avoid the additional columns, one way is to do as was pointed out in a comment, i.e. do removeAllColumns() before you go on creating your own columns.
Another approach would be to do new Grid<>() instead of new Grid<>(String.class). The main difference is that the second constructor uses reflection on the provided class and automatically configures columns for anything that looks like regular Java bean properties.

I would highly prefer to use grid.removeColumnByKey rather than removeAllColumns()
You can also use grid.setColumns to specify order of columns.
I will add link to vaadin documentantion for grid with java examples which is realy helpfull. enter link description here

I did something similar to adding the Strings in TextAreas. Because I needed some formatting, I added the text using StringBuilder.
List<String> details = getDetails();
StringBuilder builder = new StringBuilder();
for (String detail : details) {
TextArea ta = new TextArea();
ta.setSizeFull();
ta.setMaxHeight("100px");
ta.setValue(builder.append(detail).toString());
((Span) content).add(ta);
((Span) content).add(new Hr());
}
The result is like this:

Try out this
final Grid<String> grid = new Grid<>();
grid.setItems(new ArrayList<String>());
grid.addColumn(item -> item).setHeader("Value");

How to use (browser)autocomplete with Vaadin 10 TextField

I try to build an reservation Form with vaadin 10 while building it i encounterd the problem, that the autocompletion we know from every form on te web doesn't work. I put in an name field the name press submit an the next time i want to re-enter the name i need to write it out again.
My code looks like that (shortend):
TextField name = new TextField();
Button save = new Button("submit");
save.addClickListener(event -> save());
name.setAutocomplete(Autocomplete.ON);
add(name);
add(save);
i had the hopes that Autocomplete.On does the magic for me but it seems not to work. Maybe the way the save methode works screw things up?
the methode is rather big i just simplify it
private void save() {
--save everything to db
--remove all fields
--replace the fields with text saying reservation done
}

found out that someone created issue https://github.com/vaadin/vaadin-text-field/issues/156
seems to be an Shadow DOM limitation
Related issues:
https://bugs.chromium.org/p/chromium/issues/detail?id=746593
https://bugs.webkit.org/show_bug.cgi?id=172567
Edit:
for auto completion for my loginForm i got it working with adding
class xyz extends Div implements PageConfigurator{
...
#Override
public void configurePage(InitialPageSettings settings) {
settings.addInlineWithContents(
InitialPageSettings.Position.PREPEND,
"window.customElements=window.customElements||{};
window.customElements.forcePolyfill=true;
window.ShadyDOM={force:true};",
InitialPageSettings.WrapMode.JAVASCRIPT);
}

I came across this issue recently with Vaadin 14 and a custom login form.
Chrome only offers auto-filling fields (and also save login details) if it can see the input tags with name attributes in the Light DOM, but Vaadin creates TextFields with all of its elements inside of a Shadow DOM hidden.
Solution is to create a reference with <input slot="input"> inside the parent <vaadin-text-field> as part of Light DOM. All the styles and everything will still be in the Shadow DOM but Chrome now can see the input fields for auto-completion.
Kotlin code:
val username = TextField().apply {
element.setAttribute("name", "username")
element.appendChild(Element("input").setAttribute("slot", "input"))
}
val password = PasswordField().apply {
element.setAttribute("name", "password")
element.appendChild(Element("input").setAttribute("slot", "input"))
}
add(username, password)

Is it possible to add 'Open a web link action' action to acroform field programmatically using iText?

In Adobe Acrobat there is a possibility to add 'Open a web link action' to acroform. Is it possible to do so with iText usind already existing acroform?
I was unable to find any mention about it at iText docs and therefore tried to create new acrofield programmatically and add this action to it, but without success. Here's my code:
PdfReader pdfReader = new PdfReader(templateStream);
PdfStamper stamper = new PdfStamper(pdfReader, new FileOutputStream("delivery.pdf"));
stamper.setFormFlattening(true);
stamper.getAcroFields().setField("package", packages);
stamper.getAcroFields().setField("purchase_id", purchaseId);
stamper.getAcroFields().setField("activation_code", activationCode);
if (partner != "") {
PdfFormField field = PdfFormField.createTextField(stamper.getWriter(), false,
false, 100);
field.setFieldName("partner");
PdfAction action = new PdfAction(partner);
field.setAction(action);
field.setColor(new BaseColor(0,0,255));
PdfAppearance appearance = stamper.getUnderContent(1).
createAppearance(200, 20);
appearance.setFontAndSize(BaseFont.createFont(BaseFont.HELVETICA, BaseFont.WINANSI, BaseFont.NOT_EMBEDDED), 12f);
appearance.setColorFill(BaseColor.BLUE);
field.setAppearance(PdfAnnotation.APPEARANCE_DOWN, appearance);
field.setDefaultAppearanceString(appearance);
stamper.getAcroFields().setField("partner", "Click here to show partner's web site");
}
The resulting PDF document is shown without partner field. Please point me to some docs or to mistake at my code.

You are trying to add interactivity to a form. However, you are also throwing away all interactivity by using this line:
stamper.setFormFlattening(true);
You also claim that you are adding an extra field. As far as I can see, that claim is false. You create a field name field (and you create it the hard way; I would expect you to use the TextField class instead). However, I don't see you adding that field anywhere. I miss the following line:
stamper.addAnnotation(field, 1);
Note that this line doesn't make sense:
stamper.getAcroFields().setField("partner", "Click here to show partner's web site");
Why would you create a field first (and possibly add a caption) and then change it immediately afterwards? Why not create the field correctly from the start?
Finally, it seems that you want to create a button that can be clicked by people. Then why are you creating a text field? Wouldn't it make more sense to create a push button?
This is an example of a question to which a machine would respond: Too many errors... Maybe you should consider reading the documentation before trying to fix your code.

Swt + Jface application

I want to use some libraries from eclipse to create standalone application.
JFace provides for instance SourceViewer, which is great if you need to show some code in your app (that is what i need). SourceViewer looks like that eclipse editor area and you can configure it as you want. It is really great.
The SourceViewer is configured via
public void configure(SourceViewerConfiguration configuration)
There is JavaSourceViewerConfiguration, which is subclass of SourceViewerConfiguration and it should be good if you want show Java code.
This is JavaSourceViewerConfiguration constructor.
public JavaSourceViewerConfiguration(IColorManager colorManager, IPreferenceStore preferenceStore, ITextEditor editor, String partitioning)
The last two parameters could be null, so the QUESTION is how to obtain properly configured IColorManager and IPreferenceStore instances?
What i currently have:
SourceViewer sv = new SourceViewer(sf, new CompositeRuler(), SWT.NONE);
LineNumberRulerColumn lnRuler = new LineNumberRulerColumn();
sv.addVerticalRulerColumn(lnRuler);
PreferenceStore pf = new PreferenceStore();
IColorManager cm = (new JavaTextTools(pf)).getColorManager();
sv.configure(new JavaSourceViewerConfiguration(cm, pf, null, null));
But in this code i always got
Exception in thread "main" java.lang.NullPointerException
at org.eclipse.jdt.ui.text.JavaSourceViewerConfiguration.getConfiguredTextHoverStateMasks(JavaSourceViewerConfiguration.java:639)
at org.eclipse.jface.text.source.SourceViewer.configure(SourceViewer.java:507)
at swtPokus.Main.main(Main.java:37)
I think it is because that PreferenceStore pf should be somehow configured so it contains keys and values which are used by the SourceViewer.
Question2 is where to get those value for PreferenceStore?

How can i disable a button when the model is not updated?

In my UI i have 2 text field and and 2 buttons .I am using jface data binding to bind the text field and i am doing the validation and depending on the validation success the model is updated other wise it will not.I want my button to respond accordingly .Like if my model is not updated than i want to disable my button.One more thing that i do anot want to do hard coding .so is there any way to that without hard coding.
In other way I want to bind a button to text field so that when the text field has some unwanted value than the button should be disabled .In the other way i am doing data binding on text field which will take care when the text field does not have proper value than it will not update its model.Then i want to disable the button when the value is not proper can i do that.Any pointer on this helps me a lot.

You can make use of below listener. Add listener to your Observable
org.eclipse.core.databinding.observable.value.IValueChangeListener

After some research, I found that I have to observe the enable/disable property of the button and bind it with the current emf databinding context. Detail of the function which I have used is given below:
void bindEnablementButtonToValidationStatus(Button button, EMFDataBindingContext ctx) {
IObservableValue buttonEnable = SWTObservables.observeEnabled(button);
IObservableValue validationStatus = new AggregateValidationStatus(
ctx.getValidationRealm(),
ctx.getBindings(),
AggregateValidationStatus.MAX_SEVERITY);
ctx.bindValue(buttonEnable, validationStatus,
new EMFUpdateValueStrategy(
UpdateValueStrategy.POLICY_NEVER),
new EMFUpdateValueStrategy().setConverter(
new Converter(IStatus.class, Boolean.TYPE) {
public Object convert(Object fromObject) {
return new Boolean(((IStatus)fromObject).isOK());
}
}));
}