Drag-and-drop

From Academic Kids

In computer graphical user interfaces, drag-and-drop is the action of (or support for the action of) clicking on a virtual object and dragging it onto another virtual object. The basic sequence involved in drag-and-drop is:

Press, and hold down, the button on the mouse or other pointing device, to "grab" the object,
"Drag" the object/cursor/pointing device to the desired location,
"Drop" the object by releasing the button.

A common example is dragging an icon on a virtual desktop to a special trashcan icon to delete a file. In general, drag-and-drop can be used to invoke many kinds of actions, or create many kinds of associations, between two abstract objects.

Further examples include:

Dragging a data file onto a program icon or special window for viewing or processing,
Moving or copying files to a new location/directory/folder,
Adding objects to a list of objects to be processed,
Rearranging widgets in a graphical user interface to customize their layout,
Dragging a command onto an object to which the command is to be applied,
- e.g. dragging a color onto a graphical object to change its color,
Dragging a tool to a canvas location to apply the tool at that location,
Creating a hyperlink from one location or word to another location or document.

As a feature, support for drag-and-drop is not found in all software, though it is sometimes a fast and easy-to-learn technique for users to perform tasks. Drag-and-drop is a common feature of graphical user interfaces.

Dragging requires more physical effort than moving the same pointing device without holding down any buttons. Because of this, a user cannot move as quickly and precisely while dragging (see Fitts' law). However, drag-and-drop operations have the advantage of thoughtfully chunking together two operands (the object to drag, and the drop location) into a single action (see, for example, Buxton, W. (1986). Chunking and Phrasing and the Design of Human-Computer Dialogues, Proceedings of the IFIP World Computer Congress, Dublin, Ireland, 475-480. [1] (http://www.billbuxton.com/chunking.html) ).

See also: point-and-click

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