Thinking of the rolodex slider motif of some address books,

cross reference Location Within as a way to indicate... or as a counter, where the rolodex letter thing is similar, but not identical???

Problem

Solution

Similar to the Location Within pattern but not, because you can interact with it.

Variations

There are two key sets of variations. The first is in display:

Each of these can also be interacted with in several ways:

WRAP UP...

Interaction Details

Generally sometimes visible, you have to start a movement, or select an almost hidden version to open it big enough to access the controls. Then just tap the selection to jump.

Can sometimes grab an indicator. Say this overlaps with scrollbar so see those guidelines, but discuss here, because it's part of the location indicator system...

Presentation Details

Don't jump! Scroll there. Or, if too long, simulate a scroll by accelerating, then jumping closer, then decelerating to the location. The total transition should only take 0.5-1 sec, but the transition helps a great deal in understanding that the action was carried out. One part of a list is very much the same as another, so a change may not be noticed if an instant jump occurs.

indictors, in their compressed state, may be much smaller than usual for readability; about half the normal minimum size is usually acceptable, as long as there are sufficient pixels for it to be legible. It's a hint of the function, instead.

Always must indicate the current position in this position indicator. Anything clear will do, from highlight, to bold to an indicator bar or other icon in the bar. This must also animate live when jumping to a new position. Do not allow it to disappear and then reappear when the move is completed...

Antipatterns

Examples