The callback of a state change binding is evaluated when certain states change, as specified at binding creation.
Arguments
- target
either an object of class loon or a vector that specifies the widget, layer, glyph, navigator or context completely. The widget is specified by the widget path name (e.g.
'.l0.plot'
), the remaining objects by their ids.- event
vector with state names
- callback
callback function is an R function which is called by the Tcl interpreter if the event of interest happens. Note that in loon the callback functions support different optional arguments depending on the binding type, read the details for more information