File: charts/js/TimeAxis.js
/**
* Provides functionality for drawing a time axis for use with a chart.
*
* @module charts
* @submodule axis-time
*/
/**
* TimeAxis draws a time-based axis for a chart.
*
* @class TimeAxis
* @constructor
* @extends Axis
* @uses TimeImpl
* @param {Object} config (optional) Configuration parameters.
* @submodule axis-time
*/
Y.TimeAxis = Y.Base.create("timeAxis", Y.Axis, [Y.TimeImpl], {
/**
* Calculates and returns a value based on the number of labels and the index of
* the current label.
*
* @method _getLabelByIndex
* @param {Number} i Index of the label.
* @param {Number} l Total number of labels.
* @return String
* @private
*/
_getLabelByIndex: function(i, l)
{
var min = this.get("minimum"),
max = this.get("maximum"),
increm,
label;
l -= 1;
increm = ((max - min)/l) * i;
label = min + increm;
return label;
},
/**
* Returns an object literal containing and array of label values and an array of points.
*
* @method _getLabelData
* @param {Object} startPoint An object containing x and y values.
* @param {Number} edgeOffset Distance to offset coordinates.
* @param {Number} layoutLength Distance that the axis spans.
* @param {Number} count Number of labels.
* @param {String} direction Indicates whether the axis is horizontal or vertical.
* @param {Array} Array containing values for axis labels.
* @return Array
* @private
*/
_getLabelData: function(constantVal, staticCoord, dynamicCoord, min, max, edgeOffset, layoutLength, count, dataValues)
{
var dataValue,
i,
points = [],
values = [],
point,
offset = edgeOffset;
dataValues = dataValues || this._getDataValuesByCount(count, min, max);
for(i = 0; i < count; i = i + 1)
{
dataValue = this._getNumber(dataValues[i]);
if(dataValue <= max && dataValue >= min)
{
point = {};
point[staticCoord] = constantVal;
point[dynamicCoord] = this._getCoordFromValue(
min,
max,
layoutLength,
dataValue,
offset
);
points.push(point);
values.push(dataValue);
}
}
return {
points: points,
values: values
};
}
});