Class for creating horizontal and vertical slider controls.
var Slider = new Class({
Implements: [Events, Options],
Binds: ['clickedElement', 'draggedKnob', 'scrolledElement'],
options: {/*
onTick: function(intPosition){},
onChange: function(intStep){},
onComplete: function(strStep){},*/
onTick: function(position){
if (this.options.snap) position = this.toPosition(this.step);
this.knob.setStyle(this.property, position);
},
initialStep: 0,
snap: false,
offset: 0,
range: false,
wheel: false,
steps: 100,
mode: 'horizontal'
},
initialize: function(element, knob, options){
this.setOptions(options);
this.element = document.id(element);
this.knob = document.id(knob);
this.previousChange = this.previousEnd = this.step = -1;
var offset, limit = {}, modifiers = {'x': false, 'y': false};
switch (this.options.mode){
case 'vertical':
this.axis = 'y';
this.property = 'top';
offset = 'offsetHeight';
break;
case 'horizontal':
this.axis = 'x';
this.property = 'left';
offset = 'offsetWidth';
}
this.full = this.element.measure(function(){
this.half = this.knob[offset] / 2;
return this.element[offset] - this.knob[offset] + (this.options.offset * 2);
}.bind(this));
this.setRange(this.options.range);
this.knob.setStyle('position', 'relative').setStyle(this.property, this.options.initialStep ? this.toPosition(this.options.initialStep) : - this.options.offset);
modifiers[this.axis] = this.property;
limit[this.axis] = [- this.options.offset, this.full - this.options.offset];
var dragOptions = {
snap: 0,
limit: limit,
modifiers: modifiers,
onDrag: this.draggedKnob,
onStart: this.draggedKnob,
onBeforeStart: (function(){
this.isDragging = true;
}).bind(this),
onCancel: function(){
this.isDragging = false;
}.bind(this),
onComplete: function(){
this.isDragging = false;
this.draggedKnob();
this.end();
}.bind(this)
};
if (this.options.snap){
dragOptions.grid = Math.ceil(this.stepWidth);
dragOptions.limit[this.axis][1] = this.full;
}
this.drag = new Drag(this.knob, dragOptions);
this.attach();
},
attach: function(){
this.element.addEvent('mousedown', this.clickedElement);
if (this.options.wheel) this.element.addEvent('mousewheel', this.scrolledElement);
this.drag.attach();
return this;
},
detach: function(){
this.element.removeEvent('mousedown', this.clickedElement);
this.element.removeEvent('mousewheel', this.scrolledElement);
this.drag.detach();
return this;
},
set: function(step){
if (!((this.range > 0) ^ (step < this.min))) step = this.min;
if (!((this.range > 0) ^ (step > this.max))) step = this.max;
this.step = Math.round(step);
this.checkStep();
this.fireEvent('tick', this.toPosition(this.step));
this.end();
return this;
},
setRange: function(range, pos){
this.min = Array.pick([range[0], 0]);
this.max = Array.pick([range[1], this.options.steps]);
this.range = this.max - this.min;
this.steps = this.options.steps || this.full;
this.stepSize = Math.abs(this.range) / this.steps;
this.stepWidth = this.stepSize * this.full / Math.abs(this.range);
this.set(Array.pick([pos, this.step]).floor(this.min).max(this.max));
return this;
},
clickedElement: function(event){
if (this.isDragging || event.target == this.knob) return;
var dir = this.range < 0 ? -1 : 1;
var position = event.page[this.axis] - this.element.getPosition()[this.axis] - this.half;
position = position.limit(-this.options.offset, this.full -this.options.offset);
this.step = Math.round(this.min + dir * this.toStep(position));
this.checkStep();
this.fireEvent('tick', position);
this.end();
},
scrolledElement: function(event){
var mode = (this.options.mode == 'horizontal') ? (event.wheel < 0) : (event.wheel > 0);
this.set(mode ? this.step - this.stepSize : this.step + this.stepSize);
event.stop();
},
draggedKnob: function(){
var dir = this.range < 0 ? -1 : 1;
var position = this.drag.value.now[this.axis];
position = position.limit(-this.options.offset, this.full -this.options.offset);
this.step = Math.round(this.min + dir * this.toStep(position));
this.checkStep();
},
checkStep: function(){
if (this.previousChange != this.step){
this.previousChange = this.step;
this.fireEvent('change', this.step);
}
},
end: function(){
if (this.previousEnd !== this.step){
this.previousEnd = this.step;
this.fireEvent('complete', this.step + '');
}
},
toStep: function(position){
var step = (position + this.options.offset) * this.stepSize / this.full * this.steps;
return this.options.steps ? Math.round(step -= step % this.stepSize) : step;
},
toPosition: function(step){
return (this.full * Math.abs(this.min - step)) / (this.steps * this.stepSize) - this.options.offset;
}
});