Browser back should restore body like it was before

Description of the bug

When a dialog is shown (added to the body and set opened true), it does not get cleaned up when using browser back. Same goes with vcf tooltip. This leads to unexpected behaviour, if for example the dialog is confirmed afterwards.

Expected behavior

The dialog should be closed and removed from the body, even if it has no close or cancel action, as browser back is a “hard action”

Minimal reproducible example

Use the following two routes:

@Route("view")
public class View extends Div {

    public View() {
        add(new Button("go to dialog", e -> UI.getCurrent().navigate("dialog")));
    }

}

@Route("dialog")
public class DialogView extends Div {

    public DialogView() {
        add(new Button("open dialog", e -> {
            Dialog dialog = new Dialog(new Span("Do you really want to send?"));
            dialog.getFooter().add(new Button("confirm", ev -> {
                Span result = new Span("An error occured in the backend");
                result.getStyle().set("color", "red");
                add(result);
                dialog.setOpened(false);
            }), new Button("cancel", ev -> dialog.setOpened(false)));
            dialog.setOpened(true);
        }));
    }

}

• Go to “view” and click “go to dialog”. Click “open dialog”. A dialog opens. Click “confirm” and the backend error is displayed.
• Do that again, but before hitting confirm on the dialog, click browser back button. The dialog is still there. Now try to confirm the dialog. The error is not shown this time.

Versions

• Vaadin / Flow version: 23.1.2
• Java version: 11

[knoobie]

I would argue it’s intended, because a dialog can be shown on multiple views / routes and the developer can choose what they want with the tools available. But I’m not working for vaadin, just wanted to give you a quick workaround 😉

[taefi]

@timbo86 I can say this is not a bug since it works as intended. However, there can be some arguments about the default behavior of the dialog while navigating via menu or by manually entering the URL in the address bar or using the back and forward button in different circumstances e.g. being modal or not. Also, I can confirm this is working the same in V14 (dialog remains open when navigating with back and forward buttons).