assets.lib.Chart.js.src.Chart.Line.js Maven / Gradle / Ivy
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(function(){
"use strict";
var root = this,
Chart = root.Chart,
helpers = Chart.helpers;
var defaultConfig = {
///Boolean - Whether grid lines are shown across the chart
scaleShowGridLines : true,
//String - Colour of the grid lines
scaleGridLineColor : "rgba(0,0,0,.05)",
//Number - Width of the grid lines
scaleGridLineWidth : 1,
//Boolean - Whether to show horizontal lines (except X axis)
scaleShowHorizontalLines: true,
//Boolean - Whether to show vertical lines (except Y axis)
scaleShowVerticalLines: true,
//Boolean - Whether the line is curved between points
bezierCurve : true,
//Number - Tension of the bezier curve between points
bezierCurveTension : 0.4,
//Boolean - Whether to show a dot for each point
pointDot : true,
//Number - Radius of each point dot in pixels
pointDotRadius : 4,
//Number - Pixel width of point dot stroke
pointDotStrokeWidth : 1,
//Number - amount extra to add to the radius to cater for hit detection outside the drawn point
pointHitDetectionRadius : 20,
//Boolean - Whether to show a stroke for datasets
datasetStroke : true,
//Number - Pixel width of dataset stroke
datasetStrokeWidth : 2,
//Boolean - Whether to fill the dataset with a colour
datasetFill : true,
//String - A legend template
legendTemplate : "-legend\"><% for (var i=0; i- \"><%if(datasets[i].label){%><%=datasets[i].label%><%}%>
<%}%>
"
};
Chart.Type.extend({
name: "Line",
defaults : defaultConfig,
initialize: function(data){
//Declare the extension of the default point, to cater for the options passed in to the constructor
this.PointClass = Chart.Point.extend({
strokeWidth : this.options.pointDotStrokeWidth,
radius : this.options.pointDotRadius,
display: this.options.pointDot,
hitDetectionRadius : this.options.pointHitDetectionRadius,
ctx : this.chart.ctx,
inRange : function(mouseX){
return (Math.pow(mouseX-this.x, 2) < Math.pow(this.radius + this.hitDetectionRadius,2));
}
});
this.datasets = [];
//Set up tooltip events on the chart
if (this.options.showTooltips){
helpers.bindEvents(this, this.options.tooltipEvents, function(evt){
var activePoints = (evt.type !== 'mouseout') ? this.getPointsAtEvent(evt) : [];
this.eachPoints(function(point){
point.restore(['fillColor', 'strokeColor']);
});
helpers.each(activePoints, function(activePoint){
activePoint.fillColor = activePoint.highlightFill;
activePoint.strokeColor = activePoint.highlightStroke;
});
this.showTooltip(activePoints);
});
}
//Iterate through each of the datasets, and build this into a property of the chart
helpers.each(data.datasets,function(dataset){
var datasetObject = {
label : dataset.label || null,
fillColor : dataset.fillColor,
strokeColor : dataset.strokeColor,
pointColor : dataset.pointColor,
pointStrokeColor : dataset.pointStrokeColor,
points : []
};
this.datasets.push(datasetObject);
helpers.each(dataset.data,function(dataPoint,index){
//Add a new point for each piece of data, passing any required data to draw.
datasetObject.points.push(new this.PointClass({
value : dataPoint,
label : data.labels[index],
datasetLabel: dataset.label,
strokeColor : dataset.pointStrokeColor,
fillColor : dataset.pointColor,
highlightFill : dataset.pointHighlightFill || dataset.pointColor,
highlightStroke : dataset.pointHighlightStroke || dataset.pointStrokeColor
}));
},this);
this.buildScale(data.labels);
this.eachPoints(function(point, index){
helpers.extend(point, {
x: this.scale.calculateX(index),
y: this.scale.endPoint
});
point.save();
}, this);
},this);
this.render();
},
update : function(){
this.scale.update();
// Reset any highlight colours before updating.
helpers.each(this.activeElements, function(activeElement){
activeElement.restore(['fillColor', 'strokeColor']);
});
this.eachPoints(function(point){
point.save();
});
this.render();
},
eachPoints : function(callback){
helpers.each(this.datasets,function(dataset){
helpers.each(dataset.points,callback,this);
},this);
},
getPointsAtEvent : function(e){
var pointsArray = [],
eventPosition = helpers.getRelativePosition(e);
helpers.each(this.datasets,function(dataset){
helpers.each(dataset.points,function(point){
if (point.inRange(eventPosition.x,eventPosition.y)) pointsArray.push(point);
});
},this);
return pointsArray;
},
buildScale : function(labels){
var self = this;
var dataTotal = function(){
var values = [];
self.eachPoints(function(point){
values.push(point.value);
});
return values;
};
var scaleOptions = {
templateString : this.options.scaleLabel,
height : this.chart.height,
width : this.chart.width,
ctx : this.chart.ctx,
textColor : this.options.scaleFontColor,
fontSize : this.options.scaleFontSize,
fontStyle : this.options.scaleFontStyle,
fontFamily : this.options.scaleFontFamily,
valuesCount : labels.length,
beginAtZero : this.options.scaleBeginAtZero,
integersOnly : this.options.scaleIntegersOnly,
calculateYRange : function(currentHeight){
var updatedRanges = helpers.calculateScaleRange(
dataTotal(),
currentHeight,
this.fontSize,
this.beginAtZero,
this.integersOnly
);
helpers.extend(this, updatedRanges);
},
xLabels : labels,
font : helpers.fontString(this.options.scaleFontSize, this.options.scaleFontStyle, this.options.scaleFontFamily),
lineWidth : this.options.scaleLineWidth,
lineColor : this.options.scaleLineColor,
showHorizontalLines : this.options.scaleShowHorizontalLines,
showVerticalLines : this.options.scaleShowVerticalLines,
gridLineWidth : (this.options.scaleShowGridLines) ? this.options.scaleGridLineWidth : 0,
gridLineColor : (this.options.scaleShowGridLines) ? this.options.scaleGridLineColor : "rgba(0,0,0,0)",
padding: (this.options.showScale) ? 0 : this.options.pointDotRadius + this.options.pointDotStrokeWidth,
showLabels : this.options.scaleShowLabels,
display : this.options.showScale
};
if (this.options.scaleOverride){
helpers.extend(scaleOptions, {
calculateYRange: helpers.noop,
steps: this.options.scaleSteps,
stepValue: this.options.scaleStepWidth,
min: this.options.scaleStartValue,
max: this.options.scaleStartValue + (this.options.scaleSteps * this.options.scaleStepWidth)
});
}
this.scale = new Chart.Scale(scaleOptions);
},
addData : function(valuesArray,label){
//Map the values array for each of the datasets
helpers.each(valuesArray,function(value,datasetIndex){
//Add a new point for each piece of data, passing any required data to draw.
this.datasets[datasetIndex].points.push(new this.PointClass({
value : value,
label : label,
x: this.scale.calculateX(this.scale.valuesCount+1),
y: this.scale.endPoint,
strokeColor : this.datasets[datasetIndex].pointStrokeColor,
fillColor : this.datasets[datasetIndex].pointColor
}));
},this);
this.scale.addXLabel(label);
//Then re-render the chart.
this.update();
},
removeData : function(){
this.scale.removeXLabel();
//Then re-render the chart.
helpers.each(this.datasets,function(dataset){
dataset.points.shift();
},this);
this.update();
},
reflow : function(){
var newScaleProps = helpers.extend({
height : this.chart.height,
width : this.chart.width
});
this.scale.update(newScaleProps);
},
draw : function(ease){
var easingDecimal = ease || 1;
this.clear();
var ctx = this.chart.ctx;
// Some helper methods for getting the next/prev points
var hasValue = function(item){
return item.value !== null;
},
nextPoint = function(point, collection, index){
return helpers.findNextWhere(collection, hasValue, index) || point;
},
previousPoint = function(point, collection, index){
return helpers.findPreviousWhere(collection, hasValue, index) || point;
};
this.scale.draw(easingDecimal);
helpers.each(this.datasets,function(dataset){
var pointsWithValues = helpers.where(dataset.points, hasValue);
//Transition each point first so that the line and point drawing isn't out of sync
//We can use this extra loop to calculate the control points of this dataset also in this loop
helpers.each(dataset.points, function(point, index){
if (point.hasValue()){
point.transition({
y : this.scale.calculateY(point.value),
x : this.scale.calculateX(index)
}, easingDecimal);
}
},this);
// Control points need to be calculated in a seperate loop, because we need to know the current x/y of the point
// This would cause issues when there is no animation, because the y of the next point would be 0, so beziers would be skewed
if (this.options.bezierCurve){
helpers.each(pointsWithValues, function(point, index){
var tension = (index > 0 && index < pointsWithValues.length - 1) ? this.options.bezierCurveTension : 0;
point.controlPoints = helpers.splineCurve(
previousPoint(point, pointsWithValues, index),
point,
nextPoint(point, pointsWithValues, index),
tension
);
// Prevent the bezier going outside of the bounds of the graph
// Cap puter bezier handles to the upper/lower scale bounds
if (point.controlPoints.outer.y > this.scale.endPoint){
point.controlPoints.outer.y = this.scale.endPoint;
}
else if (point.controlPoints.outer.y < this.scale.startPoint){
point.controlPoints.outer.y = this.scale.startPoint;
}
// Cap inner bezier handles to the upper/lower scale bounds
if (point.controlPoints.inner.y > this.scale.endPoint){
point.controlPoints.inner.y = this.scale.endPoint;
}
else if (point.controlPoints.inner.y < this.scale.startPoint){
point.controlPoints.inner.y = this.scale.startPoint;
}
},this);
}
//Draw the line between all the points
ctx.lineWidth = this.options.datasetStrokeWidth;
ctx.strokeStyle = dataset.strokeColor;
ctx.beginPath();
helpers.each(pointsWithValues, function(point, index){
if (index === 0){
ctx.moveTo(point.x, point.y);
}
else{
if(this.options.bezierCurve){
var previous = previousPoint(point, pointsWithValues, index);
ctx.bezierCurveTo(
previous.controlPoints.outer.x,
previous.controlPoints.outer.y,
point.controlPoints.inner.x,
point.controlPoints.inner.y,
point.x,
point.y
);
}
else{
ctx.lineTo(point.x,point.y);
}
}
}, this);
ctx.stroke();
if (this.options.datasetFill && pointsWithValues.length > 0){
//Round off the line by going to the base of the chart, back to the start, then fill.
ctx.lineTo(pointsWithValues[pointsWithValues.length - 1].x, this.scale.endPoint);
ctx.lineTo(pointsWithValues[0].x, this.scale.endPoint);
ctx.fillStyle = dataset.fillColor;
ctx.closePath();
ctx.fill();
}
//Now draw the points over the line
//A little inefficient double looping, but better than the line
//lagging behind the point positions
helpers.each(pointsWithValues,function(point){
point.draw();
});
},this);
}
});
}).call(this);