Interface Concept: Breadcrumbs

NOTE: Please use Talk:Interface_Draft:_Breadcrumb_Concept to provide comments and/or feedback

=Definition= A breadcrumb should provide a trail for users navigating within lists, items and item details. It works historically, providing an easy way to access previously seen pages. Position and appearance are defined in the style guide. The breadcrumb is not intended as replacement for the browser back button. The browser back button is the most used element in web applications and must behave as expected.

Entry point
The breadcrumb is not displayed right from beginning. It appears/is extended as soon as the user leaves one of the pages defined here.

Overview on 'Click Levels'
The rough overview shows main functional areas and click levels from a list to an item and finally to item details such as statistics, revisions. (this is a diagram only, not a specification of the page flow R4).



Examples
The breadcrumb should grow from right to left and is extended if the user leaves the page and has no label. The trail can have up to 3 entries. Entries are cropped on the left side.

Example:

Pages and corresponding breadcrumbs generated in Public Repository

Pages and corresponding breadcrumbs generated in Depositor Workspace

If a filter setting is changed on a list, the breadcrumb is extended too.

=Reasoning=

Why the following breadcrumbs do not make sense in the PubMan context
Problem: For web applications - where items are irrevocably changed - there is no way back (except a certain undo functionality is implemented). Once an item has been changed the browser should warn. And if so, the user needs to know the difference between 'back' and 'undo'.

Path

Path breadcrumbs are dynamic and show the path that the user has taken to arrive at a page


 * PubMan does not provide a strict hierarchical structure. In many cases there is no single path to a page.

History of pages/Action history


 * This is a reasonable feature for static content. If items change at one point in time it does not make sense to jump to a page reflecting a state which is different from the current/real one.

Attribute

Attribute breadcrumbs give information that categorizes the current page.
 * Would make sense, but as pages are role dependent the attribute might reflect a wrong categorization

Why a breadcrumb makes no sense for the following functionality in PubMan
Most pages are anyway redundantly displayed in a breadcrumb or inconsistent in use, because

Simple Search
 * is anyway provided persistently inside header
 * is not clear where breadcrumb leads to (revise search via advanced search?)

Advanced Search
 * is anyway provided persistently inside header

Organisation Search
 * is anyway provided persistently inside header

Export
 * will mostly appear at the end of the breadcrumb
 * will automatically be available after any search
 * is provided persistently in the options menu

Submission(methods)
 * is inconsistent because items change

Actions
 * will be a mixture of structural breadcrumb and action history
 * as actions lead to modifications the breadcrumb is rather a undo history (not possible!!)

=Assumption= There is a certain functional area, where items do not change and where a breadcrumb could provide help (see Diagram). PubMan should provide a breadcrumb only for item lists, view item version, item details.

This additional navigation should not be called breadcrumb or be offered in a breadcrumb manner/stype in the interface because it is different.

=References=