Locator
represents a draggable graphics primitive (2D or 3D), that generates "drag" event
Locator[{x,y}]sets a locator to {x,y} initial position
Methods
EventHandler
Use it to assign a handler function for generated events:
location = {0.3,0.7};
Plot[x, {x,0,1}, Epilog->{
EventHandler[Locator[location], {
"drag"->Function[xy, location = xy]
}]
}]
Refresh[NumberForm[location, {3,2}], 1/2]