Section: New Results

Reciprocal Drag and Drop

Figure 5. Navigating a graphical object's direct manipulation history as captured by the DnD-1 model, using the Dwell-and-Spring widget.

Drag-and-drop has become ubiquitous, both on desktop computers and touch-sensitive surfaces. It is used to move and edit the geometry of elements in graphics editors, to adjust parameters using controllers such as sliders, or to manage views (e.g., moving and resizing windows, panning maps). Reverting changes made via a drag-and-drop usually entails performing the reciprocal drag-and-drop action. This can be costly as users have to remember the previous position of the object and put it back precisely. We introduced the DnD-1 model that handles all past locations of graphical objects. We redesigned the Dwell-and-Spring widget to interact with this history. Applications can implement DnD-1 to enable users to perform reciprocal drag-and-drop to any past location for both individual objects and groups of objects. We performed two user studies, whose results show that users understand DnD-1, and that Dwell-and-Spring enables them to interact with this model effectively.

This work was published in ACM ToCHI [1] .