InputRange

InputRange[min_, max_, step_:1, initial_:(min+max)/2, opts___] _EventObject

creates a basic combo of a slider and numerical input field and returns EventObject

Event generation

Every-time user drags a slider, an event in a form of number will be generated

slider = InputRange[0,1,0.1];
EventHandler[slider, Function[data,
	Print[StringTemplate["`` is a number"][data]]
]];
slider

Options

"Label"

Adds a label to a slider

slider = InputRange[0, 1, 0.1, "Label"->"Slider"]

"Topic"

Specifies which topic or pattern of an event is used

"Topic" -> name_String

emits name for each time when user drags a slider

"Topic" -> {oninput_String, onchange_String}

emits oninput when any changes occur, while onchange is emitted after the users action. Null value will suppress event generation, i.e. to make onchange only slider

"Topic" -> {Null, "Default"}

"TrackedExpression"

Adds expression to track (usually a symbol) and update the slider position

var = 0.3;
EventHandler[InputRange[0,2,0.1, var, "TrackedExpression"->Offload[var], Print]

Now you can overwrite slider position by setting

var = 0.6;

Debouncing

To prevent an event propagation, when a tracked symbol is updated use

"TrackedExpression"->{Offload[var], "Debounce"}

then you can safely write

var = 0.3;
EventHandler[InputRange[0,2,0.1, var, "TrackedExpression"->{Offload[var], "Debounce"}], Function[newValue,
	var = newValue
]]

Then InputRange will remember its state

Appearance

By the default is Automatic. Possible value: "FineTuning" - adds a fine control element to vary the range value $\pm 10\%$.

Chaining events

One can reuse another event for a new element

InputRange[event_EventObject, min_, max_, step_:1, initial_:(min+max)/2, opts___]

for example

ev = EventObject[];

InputButton[ev, "Topic"->"Button"]
InputRange[ev, 0,1,0.1, "Topic"->"Slider"]

EventHandler[ev, {
	"Button" -> Beep,
	"Slider" -> Print
}];

Applications

Control properties using knob

EventHandler[InputRange[0,1,0.1], Function[data, pos = data]];
% 
% // EventFire;
Graphics[Rectangle[{-1,0}, {1, Offload[pos]}]]

Supported output forms

• StandardForm
• WLXForm