TabSheet fires SelectedChangeEvent before the tab component is added

[schwarzwald]

Description of the bug

When a tab is added to the TabSheet and if it's the first tab, the tab sheet may automatically select this tab. This triggers the SelectedChangeEvent, but it happens before the tab component is added to the internal tabToContent map. If we want to access the selected component when the tab selection listener is notified, the tab sheet returns null.

Expected behavior

The SelectedChangeEvent should be fired after the tab component is internally registered, so that we can access is when the listener is notified.

Minimal reproducible example

var tabsheet = new TabSheet();
tabsheet.addSelectedTabChangeListener(e -> {
  if (e.getSelectedTab() != null) {
    Objects.requireNonNull(tabsheet.getComponent(e.getSelectedTab()));
  }
});
tabsheet.addTab("tab", new Div());

Versions

• Vaadin / Flow version: 24.5.0 (but may occur also on earlier versions)