{
"id": "L09",
"title": "Transfer list",
"topic": "lists",
"use": "Assign several entries of a small inventory to one record — the cost centers an employee is booked to. On the left stands what is available, on the right what is assigned, and the user moves entries back and forth while both sides stay in view. The assignment takes effect when it is saved. For a single assignment two lists are an apparatus for one hand movement; a select is enough there.",
"decisions": [
"Two selectable ed-lists side by side, available on the left and assigned on the right: the state is there at a glance, and several entries move in one go, without a dialog for each.",
"Each side moves its own selection with the button in its head — Assign on the left, Remove on the right: taking back is the same gesture as assigning, the other way round, and each button is unavailable while nothing on its side is ticked.",
"Both sides can be filtered, not only the left: the assigned side grows too. A filter keeps the ticks of the entries it hides, and the line under the list says how many of them are out of view and move along — the list's own rule for a selection beyond the view.",
"Each side names how many entries it holds in its title, and the count beside it how many of those in view are ticked; both follow every move. A side with nothing in view says why, instead of an empty frame.",
"Both sides stay sorted by cost center number, so an entry that moves lands where its number puts it and not at the end, where the order would look random.",
"After a move the focus goes to its side's filter, the next control that is still there: the button just pressed becomes unavailable.",
"Nothing applies until Save assignment: the line under the toolbar says so and counts the changes not saved yet, and an entry moved back where it came from is no change. A newly assigned entry says the same in its own row until it is saved.",
"Save assignment stores what the lists showed when it was pressed, and shows that it is saving: a move made meanwhile stays an unsaved change, not one that reads as saved without having been sent.",
"Save assignment is unavailable while nothing has changed, and its title says what makes it available, so the pointer learns it too where the line under the toolbar is out of sight."
],
"try": [
{
"do": "Tick 4210 Fleet North and 4300 Sales on the left and press Assign",
"then": "both move to the right, in the order of their numbers; the titles count 3 available and 5 assigned, and the line under the toolbar counts 2 unsaved changes"
},
{
"do": "Tick 4300 Sales on the right, then type 42 into the filter on the right",
"then": "only the cost centers whose number or name holds 42 stay in view, the title still counts all 5 assigned, and the line under the list says 1 ticked cost center is out of view"
},
{
"do": "Tick 4210 Fleet North on the right and press Remove",
"then": "both ticked cost centers go back to the left, the one out of view included, and the line counts no unsaved change any more, because a move back is no change"
},
{
"do": "Assign 4100 Administration and press Save assignment, then at once assign 4310 Marketing",
"then": "the toast confirms the assignment for Timo Brandt, 4100 Administration no longer says it is new, and 4310 Marketing stays 1 unsaved change"
}
],
"revision": 1,
"changes": [],
"reviewed": false,
"source": "\n \n\n
\n
\n \n \n Save assignment\n \n \n
\n
\n\n
\n
\n
\n
\n \n \n Assign\n \n \n
\n
\n\n
\n
\n
\n \n \n Remove\n \n \n
\n
\n
\n\n
\n