Pass a variable in UI.navigation

Flow
1

I want to pass a variable to a page. I have 4 different buttons that have a ClickListener that navigates to the page, and I want also pass 4 possible different values. The first idea was using the URL:

localhost:8080/second-page?value=1

I try to find a way to get value from it, but nothing wants to work.

I try also a different way using the plug-in URL Parameter Mapping but return only null values.

Any idea?

2

Please show us what you’ve tried. What you are looking for are QueryParameter available in all Before and AfterEnterEvents’ Location Object.

3

What @knoobie said.
This example code should work for your case:

@Route("second-page")
public class SecondPage extends VerticalLayout implements HasUrlParameter<Integer> {

    @Override
    public void setParameter(BeforeEvent beforeEvent, @OptionalParameter Integer parameter) {
        // prints '1' for localhost:8080/second-page?value=1
        beforeEvent.getLocation().getQueryParameters().getSingleParameter("value")
                .ifPresent(System.out::println);
    }
}
4

Adding to @knoobie and @mikhail.21 comments, make sure to read about the Navigation Lifecycle. Parameters are read/processed before the view itself is built and need to be saved to variables than can then be read from your constructor/initialization methods.