How to expand a preference section by default when opening the preference dialog programmatically

[jdneo]

I'm using PreferencesUtil.createPreferenceDialogOn to open the preference dialog with certain pages.

The problem I have is that, in the opened preference dialog, the page in the same section is collapse:

Is there an api to make the section be expanded by default? Like:

[iloveeclipse]

Briefly looking at the code I don't see this is implemented. I guess org.eclipse.ui.internal.dialogs.FilteredPreferenceDialog need to be changed to allow tree expansion if a page is opened that has sub-pages. PR's are welcome :-)

[mickaelistria]

I'm not sure the current behavior is specified nor that it is the best one. The one you're targetting seems more generally better. So instead of an API, I think we can consider just fixing it by default in the code. I would recommend you submit a PR changing the default behavior.

[jdneo]

Tried to do that in #3153