jQuery Knob
- canvas based ; no png or jpg sprites.
- touch, mouse and mousewheel, keyboard events implemented.
- downward compatible ; overloads an input element.
Example
<input type="text" value="75" class="dial">
<script>
$(function() {
$(".dial").knob();
});
</script>
Options
Options are provided as attributes 'data-option':
<input type="text" class="dial" data-min="-50" data-max="50">
... or in the "knob()" call :
$(".dial").knob({
'min':-50,
'max':50
});
The following options are supported :
Behaviors :
- min : min value | default=0.
- max : max value | default=100.
- step : step size | default=1.
- angleOffset : starting angle in degrees | default=0.
- angleArc : arc size in degrees | default=360.
- stopper : stop at min & max on keydown/mousewheel | default=true.
- readOnly : disable input and events | default=false.
- rotation : direction of progression | default=clockwise.
UI :
- cursor : display mode "cursor", cursor size could be changed passing a numeric value to the option, default width is used when passing boolean value "true" | default=gauge.
- thickness : gauge thickness.
- lineCap : gauge stroke endings. | default=butt, round=rounded line endings
- width : dial width.
- height : dial height.
- displayInput : default=true | false=hide input.
- displayPrevious : default=false | true=displays the previous value with transparency.
- fgColor : foreground color.
- inputColor : input value (number) color.
- font : font family.
- fontWeight : font weight.
- bgColor : background color.
Hooks
<script>
$(".dial").knob({
'release' : function (v) { /*make something*/ }
});
</script>
-
'release' : executed on release
Parameters :
- value : int, current value
-
'change' : executed at each change of the value
Parameters :
- value : int, current value
-
'draw' : when drawing the canvas
Context :
- this.g : canvas context 2D (see Canvas documentation)
- this.$ : jQuery wrapped element
- this.o : options
- this.i : input
- ... console.log(this);
-
'cancel' : triggered on [esc] keydown
-
'format' : allows to format output (add unit %, ms ...)
The scope (this) of each hook function is the current Knob instance (refer to the demo code).
Example
<input type="text" value="75" class="dial">
<script>
$(".dial").knob({
'change' : function (v) { console.log(v); }
});
</script>
Dynamically configure
<script>
$('.dial').trigger(
'configure',
{
"min":10,
"max":40,
"fgColor":"#FF0000",
"skin":"tron",
"cursor":true
}
);
</script>
Set the value
<script>
$('.dial')
.val(27)
.trigger('change');
</script>
Supported browser
Tested on Chrome, Safari, Firefox, IE>=8.0 (IE8.0 with excanvas).
