Scriptaculous/Slider.js

   1 // Copyright (c) 2005-2007 Marty Haught, Thomas Fuchs
   2 //
   3 // script.aculo.us is freely distributable under the terms of an MIT-style license.
   4 // For details, see the script.aculo.us web site: http://script.aculo.us/
   5
   6 JSAN.use('Prototype');
   7
   8 if (!Control) var Control = { };
   9
  10 // options:
  11 //  axis: 'vertical', or 'horizontal' (default)
  12 //
  13 // callbacks:
  14 //  onChange(value)
  15 //  onSlide(value)
  16 Control.Slider = Class.create({
  17   initialize: function(handle, track, options) {
  18     var slider = this;
  19
  20     if (Object.isArray(handle)) {
  21       this.handles = handle.collect( function(e) { return $(e) });
  22     } else {
  23       this.handles = [$(handle)];
  24     }
  25
  26     this.track   = $(track);
  27     this.options = options || { };
  28
  29     this.axis      = this.options.axis || 'horizontal';
  30     this.increment = this.options.increment || 1;
  31     this.step      = parseInt(this.options.step || '1');
  32     this.range     = this.options.range || $R(0,1);
  33
  34     this.value     = 0; // assure backwards compat
  35     this.values    = this.handles.map( function() { return 0 });
  36     this.spans     = this.options.spans ? this.options.spans.map(function(s){ return $(s) }) : false;
  37     this.options.startSpan = $(this.options.startSpan || null);
  38     this.options.endSpan   = $(this.options.endSpan || null);
  39
  40     this.restricted = this.options.restricted || false;
  41
  42     this.maximum   = this.options.maximum || this.range.end;
  43     this.minimum   = this.options.minimum || this.range.start;
  44
  45     // Will be used to align the handle onto the track, if necessary
  46     this.alignX = parseInt(this.options.alignX || '0');
  47     this.alignY = parseInt(this.options.alignY || '0');
  48
  49     this.trackLength = this.maximumOffset() - this.minimumOffset();
  50
  51     this.handleLength = this.isVertical() ?
  52       (this.handles[0].offsetHeight != 0 ?
  53         this.handles[0].offsetHeight : this.handles[0].style.height.replace(/px$/,"")) :
  54       (this.handles[0].offsetWidth != 0 ? this.handles[0].offsetWidth :
  55         this.handles[0].style.width.replace(/px$/,""));
  56
  57     this.active   = false;
  58     this.dragging = false;
  59     this.disabled = false;
  60
  61     if (this.options.disabled) this.setDisabled();
  62
  63     // Allowed values array
  64     this.allowedValues = this.options.values ? this.options.values.sortBy(Prototype.K) : false;
  65     if (this.allowedValues) {
  66       this.minimum = this.allowedValues.min();
  67       this.maximum = this.allowedValues.max();
  68     }
  69
  70     this.eventMouseDown = this.startDrag.bindAsEventListener(this);
  71     this.eventMouseUp   = this.endDrag.bindAsEventListener(this);
  72     this.eventMouseMove = this.update.bindAsEventListener(this);
  73
  74     // Initialize handles in reverse (make sure first handle is active)
  75     this.handles.each( function(h,i) {
  76       i = slider.handles.length-1-i;
  77       slider.setValue(parseFloat(
  78         (Object.isArray(slider.options.sliderValue) ?
  79           slider.options.sliderValue[i] : slider.options.sliderValue) ||
  80          slider.range.start), i);
  81       h.makePositioned().observe("mousedown", slider.eventMouseDown);
  82     });
  83
  84     this.track.observe("mousedown", this.eventMouseDown);
  85     document.observe("mouseup", this.eventMouseUp);
  86     document.observe("mousemove", this.eventMouseMove);
  87
  88     this.initialized = true;
  89   },
  90   dispose: function() {
  91     var slider = this;
  92     Event.stopObserving(this.track, "mousedown", this.eventMouseDown);
  93     Event.stopObserving(document, "mouseup", this.eventMouseUp);
  94     Event.stopObserving(document, "mousemove", this.eventMouseMove);
  95     this.handles.each( function(h) {
  96       Event.stopObserving(h, "mousedown", slider.eventMouseDown);
  97     });
  98   },
  99   setDisabled: function(){
 100     this.disabled = true;
 101   },
 102   setEnabled: function(){
 103     this.disabled = false;
 104   },
 105   getNearestValue: function(value){
 106     if (this.allowedValues){
 107       if (value >= this.allowedValues.max()) return(this.allowedValues.max());
 108       if (value <= this.allowedValues.min()) return(this.allowedValues.min());
 109
 110       var offset = Math.abs(this.allowedValues[0] - value);
 111       var newValue = this.allowedValues[0];
 112       this.allowedValues.each( function(v) {
 113         var currentOffset = Math.abs(v - value);
 114         if (currentOffset <= offset){
 115           newValue = v;
 116           offset = currentOffset;
 117         }
 118       });
 119       return newValue;
 120     }
 121     if (value > this.range.end) return this.range.end;
 122     if (value < this.range.start) return this.range.start;
 123     return value;
 124   },
 125   setValue: function(sliderValue, handleIdx){
 126     if (!this.active) {
 127       this.activeHandleIdx = handleIdx || 0;
 128       this.activeHandle    = this.handles[this.activeHandleIdx];
 129       this.updateStyles();
 130     }
 131     handleIdx = handleIdx || this.activeHandleIdx || 0;
 132     if (this.initialized && this.restricted) {
 133       if ((handleIdx>0) && (sliderValue<this.values[handleIdx-1]))
 134         sliderValue = this.values[handleIdx-1];
 135       if ((handleIdx < (this.handles.length-1)) && (sliderValue>this.values[handleIdx+1]))
 136         sliderValue = this.values[handleIdx+1];
 137     }
 138     sliderValue = this.getNearestValue(sliderValue);
 139     this.values[handleIdx] = sliderValue;
 140     this.value = this.values[0]; // assure backwards compat
 141
 142     this.handles[handleIdx].style[this.isVertical() ? 'top' : 'left'] =
 143       this.translateToPx(sliderValue);
 144
 145     this.drawSpans();
 146     if (!this.dragging || !this.event) this.updateFinished();
 147   },
 148   setValueBy: function(delta, handleIdx) {
 149     this.setValue(this.values[handleIdx || this.activeHandleIdx || 0] + delta,
 150       handleIdx || this.activeHandleIdx || 0);
 151   },
 152   translateToPx: function(value) {
 153     return Math.round(
 154       ((this.trackLength-this.handleLength)/(this.range.end-this.range.start)) *
 155       (value - this.range.start)) + "px";
 156   },
 157   translateToValue: function(offset) {
 158     return ((offset/(this.trackLength-this.handleLength) *
 159       (this.range.end-this.range.start)) + this.range.start);
 160   },
 161   getRange: function(range) {
 162     var v = this.values.sortBy(Prototype.K);
 163     range = range || 0;
 164     return $R(v[range],v[range+1]);
 165   },
 166   minimumOffset: function(){
 167     return(this.isVertical() ? this.alignY : this.alignX);
 168   },
 169   maximumOffset: function(){
 170     return(this.isVertical() ?
 171       (this.track.offsetHeight != 0 ? this.track.offsetHeight :
 172         this.track.style.height.replace(/px$/,"")) - this.alignY :
 173       (this.track.offsetWidth != 0 ? this.track.offsetWidth :
 174         this.track.style.width.replace(/px$/,"")) - this.alignX);
 175   },
 176   isVertical:  function(){
 177     return (this.axis == 'vertical');
 178   },
 179   drawSpans: function() {
 180     var slider = this;
 181     if (this.spans)
 182       $R(0, this.spans.length-1).each(function(r) { slider.setSpan(slider.spans[r], slider.getRange(r)) });
 183     if (this.options.startSpan)
 184       this.setSpan(this.options.startSpan,
 185         $R(0, this.values.length>1 ? this.getRange(0).min() : this.value ));
 186     if (this.options.endSpan)
 187       this.setSpan(this.options.endSpan,
 188         $R(this.values.length>1 ? this.getRange(this.spans.length-1).max() : this.value, this.maximum));
 189   },
 190   setSpan: function(span, range) {
 191     if (this.isVertical()) {
 192       span.style.top = this.translateToPx(range.start);
 193       span.style.height = this.translateToPx(range.end - range.start + this.range.start);
 194     } else {
 195       span.style.left = this.translateToPx(range.start);
 196       span.style.width = this.translateToPx(range.end - range.start + this.range.start);
 197     }
 198   },
 199   updateStyles: function() {
 200     this.handles.each( function(h){ Element.removeClassName(h, 'selected') });
 201     Element.addClassName(this.activeHandle, 'selected');
 202   },
 203   startDrag: function(event) {
 204     if (Event.isLeftClick(event)) {
 205       if (!this.disabled){
 206         this.active = true;
 207
 208         var handle = Event.element(event);
 209         var pointer  = [Event.pointerX(event), Event.pointerY(event)];
 210         var track = handle;
 211         if (track==this.track) {
 212           var offsets  = Position.cumulativeOffset(this.track);
 213           this.event = event;
 214           this.setValue(this.translateToValue(
 215            (this.isVertical() ? pointer[1]-offsets[1] : pointer[0]-offsets[0])-(this.handleLength/2)
 216           ));
 217           var offsets  = Position.cumulativeOffset(this.activeHandle);
 218           this.offsetX = (pointer[0] - offsets[0]);
 219           this.offsetY = (pointer[1] - offsets[1]);
 220         } else {
 221           // find the handle (prevents issues with Safari)
 222           while((this.handles.indexOf(handle) == -1) && handle.parentNode)
 223             handle = handle.parentNode;
 224
 225           if (this.handles.indexOf(handle)!=-1) {
 226             this.activeHandle    = handle;
 227             this.activeHandleIdx = this.handles.indexOf(this.activeHandle);
 228             this.updateStyles();
 229
 230             var offsets  = Position.cumulativeOffset(this.activeHandle);
 231             this.offsetX = (pointer[0] - offsets[0]);
 232             this.offsetY = (pointer[1] - offsets[1]);
 233           }
 234         }
 235       }
 236       Event.stop(event);
 237     }
 238   },
 239   update: function(event) {
 240    if (this.active) {
 241       if (!this.dragging) this.dragging = true;
 242       this.draw(event);
 243       if (Prototype.Browser.WebKit) window.scrollBy(0,0);
 244       Event.stop(event);
 245    }
 246   },
 247   draw: function(event) {
 248     var pointer = [Event.pointerX(event), Event.pointerY(event)];
 249     var offsets = Position.cumulativeOffset(this.track);
 250     pointer[0] -= this.offsetX + offsets[0];
 251     pointer[1] -= this.offsetY + offsets[1];
 252     this.event = event;
 253     this.setValue(this.translateToValue( this.isVertical() ? pointer[1] : pointer[0] ));
 254     if (this.initialized && this.options.onSlide)
 255       this.options.onSlide(this.values.length>1 ? this.values : this.value, this);
 256   },
 257   endDrag: function(event) {
 258     if (this.active && this.dragging) {
 259       this.finishDrag(event, true);
 260       Event.stop(event);
 261     }
 262     this.active = false;
 263     this.dragging = false;
 264   },
 265   finishDrag: function(event, success) {
 266     this.active = false;
 267     this.dragging = false;
 268     this.updateFinished();
 269   },
 270   updateFinished: function() {
 271     if (this.initialized && this.options.onChange)
 272       this.options.onChange(this.values.length>1 ? this.values : this.value, this);
 273     this.event = null;
 274   }
 275 });