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To select multiple items, you repeatedly select single items using their checkboxes until all your items are selected (toggle selection). Alternatively, use a rubber band rectangle when using a mouse to select the items (object selection). Note that in the latter case, the checkboxes of all selected items are also checked as soon as you release the mouse button. A previously selected group of items is first deselected before the newly defined group becomes selected.
Any visible and enabled view for item details will refresh immediately and show additional details on the set of selected items (e.g. summary of all sizes, number of selected items, etc.).
Select and deselect all items
Views supporting the selection of multiple items shall also always offer an additional checkbox to toggle the selection of all items (visible or invisible) in the view. Checking it first selects all items, checking it again de-selects the items.
Indicate number of selected items
Any view supporting the selection of multiple items shall indicate the total number of currently selected items.
Open an item for editing or further inspection
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If you click on a list or tree view offering item selection and you do not click on a selectable item, all previously selected items are deselected. The items are also deselected if you toggle the "select all items" checkbox to first select all, then deselect all items (see #Select and deselect all items).
Deselect a single item
You may deselect a single item by unchecking its checkbox or clicking on it while holding down the Command/Ctrl modified key. When using the keyboard, move the keyboard focus on the item, then hit SPACE - hitting SPACE thus toggles a selection. On a touch device, you may only uncheck an item's checkbox to deselect it.
If an item is deselected, all other selected items remain selected.
Executing an operation on selected items
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| Mouse | Keyboard | Touch |
|---|---|---|---|
Focus an item | move mouse over it | move keyboard focus using arrow keys | (not supported) |
Select an item | click it or tick its checkbox | move keyboard focus, then hit SPACE | tap on it or tick its checkbox |
Deselect an item | click it while holding Command/Ctrl, or | move keyboard focus, then hit SPACE | uncheck its checkbox |
Open an item | double-click it, or | double-tap it, or | select it, then it Command/Ctrl-ENTER, or |
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