Drag to create

Drag to create makes the object and sizes it in the same gesture. Press where it should start, pull to where it should end, let go, and the thing exists at exactly that extent. There is no separate step where the interface asks how big, because the question was answered by the stroke. It is how an event gets drawn across two hours in a scheduler, how a rectangle or an artboard appears on a canvas, and how a crop, a selection region or a time range gets made in an editor.

What it buys is one gesture instead of three. The alternative is a button that makes a default-sized object, which the reader then has to move and then resize, and each of those is a separate act of aiming. The gesture also puts the object where the reader was already looking, which a dialog cannot do. That is why it survives in tools where speed matters and disappears in tools where objects have no extent worth choosing.

It has two failure modes and both are worth designing for. The first is the accidental object: any press on an empty surface is now potentially a creation, so a slipped finger leaves litter. The fix is a threshold, which is a drag threshold doing its usual job in an unusual place: under a few pixels of travel the press is a click and nothing is made. The second fix is that whatever is made arrives selected and undoable, so the reader is one keystroke from having never made it. The other failure mode is discoverability, because an empty surface says nothing about the gesture at all. A short line of help in the empty state, or a ghost preview appearing as soon as the press moves, is usually the whole of the answer.

Three neighbouring gestures are all drags and none of them are this one. Brushing drags across a chart to select a range of data that is already plotted, so nothing new comes into existence. Drag and drop moves something that already exists from one place to another. And a resize handle changes the extent of an existing object, which is the second half of this gesture performed later and on its own. The tell for this term is that the object was not there before the press.