Most often used to configure a set of items (for a report, a toolbar, etc) when
- a (often large) pool of options exists
- order or sequence of the items may have some relevance to the user
- the amount or order of options might change over time or by use (optional)
Users must be able to see the available pool of items, see the current set of items that exists, and have a means to add and remove items from their current set.
Alternative: "Meta Pattern"
Title, summary and context stay the same
It has to be absolutely clear to the user which items he can select from and which ones are already selected. The size of the pool of items to select from may range from only a few to large amounts of items and changing the selection might be a common or rare usecase.
Ask yourself two questions:
1. Will the selected items be displayed regularly but only rarely changed or will they only be displayed when the selection is changed?
- In the first case, use the Picker dialog.
- In the second case, ask yourself the second question
2. How many items are usually in the pool?
- If there are less than ten, use the List of checkboxes
- If there are more than ten, use the Two lists with arrow buttons