Behavior in detailview

Support
#1

Hi everyone, I have a detailView of class A with some fields and a datagrid to a class B (o2m relationship) , the B class has a boolean field “principal”. I must assure that there is only one B with principal to true. So i write a method to do that in the “beforeSave” of B detailview, but for some reason the other records remains doesn’t change their principal value. Any ideas why? in the before save code it’s like this
if record.getPrincipal()){ record.getA().getB().stream() .filter(Objects::nonNull) .filter(p -> !record.getCode().equals(p.getCode())) .forEach(p -> p.setPrincipal(false)); }
Thanks

#2

Hi!

Could you please provide a small test project that reproduces the issue?

Best regards,
Dmitriy

#3

simple-app.tar.gz (52.4 KB)

#4

Hi!

Thank you for demo project.

Unfortunately, I encountered some difficulties while using it:

  1. The project lacked build system information, making it impossible to build the project initially. Furthermore, there’s no objective indication of the project’s affiliation with a specific Jamix version. To avoid this, use the framework’s built-in project archiver: ./gradlew zipProject
  2. You used a postgres database defined on your local machine. My machine doesn’t have a postgres database. Naturally, running the application with this configuration is impossible. To transfer the test project, you need to use a transferable database, such as an H2 File.

On my test project in your case, this problem does not occur:
test-project.zip (122.4 KB)

I hope my test project will help you fix your own.

Best regards,
Dmitriy

Offtop:

I’ll also offer a word of caution. I saw in your code that you use a checkbox component as a renderer. Using a full-fledged component can have a negative impact on performance, because creating a component entails creating both its client-part and server-part. If you have a lot of entities and a lot of checkboxes, this will definitely slow down the app. It’s more optimal to use icons to indicate Boolean values. For example:

    @Supply(to = "childDataGrid.principal", subject = "renderer")
    private Renderer<B> childDataGridPrincipalRenderer() {
        return new ComponentRenderer<>(b -> Boolean.TRUE.equals(b.getPrincipal())
                ? icons.get(JmixFontIcon.CHECK_SQUARE_O)
                : icons.get(JmixFontIcon.THIN_SQUARE));
    }