我有一个设计要求,要显示包含5个趋势数据数据集的折线图.沿着笔划线的每个数据值需要在其相应的数据点处显示数据值标签.
不幸的是,我无法在Charts.js中找到满足此要求的选项.
有没有可以帮助我的解决方法？
我也把它发布在小提琴上：http://jsfiddle.net/s9eannLh/
非常感谢！
var data = {
labels: ["","Jun 2013","Jul 2013","Aug 2013","Sep 2013","Oct 2013","Nov 2013","Dec 2013","Jan 2014","Feb 2014","Mar 2014","Apr 2014","May 2014"],datasets: [
{
label: "hemoglobin_1",title: "test",fillColor: "transparent",strokeColor: "#65204c",pointColor: "#65204c",pointHighlightStroke: "#FFF",data: [null,5.7,5.8,5.9,6.7,6.5,6.4,6.4]
},{
label: "hemoglobin_2",strokeColor: "#ed7141",pointColor: "#ed7141",15.5,15.6,15.2,15.1,15.8,17,17.4,16.8,16.4,16.4]
},{
label: "hemoglobin_3",strokeColor: "#de4760",pointColor: "#de4760",37.1,37,37.2,37.6,36.9,36.8,38,37.5,39.1,37.5]
},{
label: "hemoglobin_4",strokeColor: "#fdcf7e",pointColor: "#fdcf7e",29.9,30.4,29.5,29.6,30.2,29.4,29.8,26.9,27,28.5,26.8,28.5]
},{
label: "hemoglobin_5",strokeColor: "#a33a59",pointColor: "#a33a59",11.8,11.4,11.9,11.5,12.2,11.7,10.9,10.7,11.3,11.3]
}
]
};
var options = {
responsive: true,scaleOverride: true,scaleSteps: 10,scaleStepWidth: 5,scaleStartValue: 0,showTooltips: false,pointDot: true,pointDotRadius : 6,datasetStrokeWidth : 3,bezierCurve : false,scaleShowHorizontalLines: false,scaleGridLineWidth : 2,scaleGridLineColor : "#EEEEEE",scaleLineWidth: 3,scaleLineColor: "#000000",scaleFontFamily: '"Gotham Book",sans-serif',scaleFontSize: 18
}
var ctx = $("#myChart").get(0).getContext("2d");
var Trends = new Chart(ctx).Line(data,options);
最佳答案
我终于找到了这个问题的解决方案.
我意识到我可以访问DOM中的图表对象：
Trends.datasets
在五个数据集中的每个数据集中,存在包含x&的点对象. y职位：
Trends.datasets[0..4].points
所以我使用Chart.js中的全局配置函数通过回调解析了这些点：
// Function - Will fire on animation progression.
onAnimationProgress: function(){},// Function - Will fire on animation completion.
onAnimationComplete: function(){}
我发现我必须在响应时使用onAnimationComplete：true,因为点标签会在resize事件中消失.
一旦我在回调中找到了点,我就会在画布上写下我想要的标签.
我对代码的补充是：
var options = {
onAnimationProgress: function() { drawDatasetPointsLabels() },onAnimationComplete: function() { drawDatasetPointsLabels() }
}
function drawDatasetPointsLabels() {
ctx.font = '.9rem "Gotham Book",sans-serif';
ctx.fillStyle = '#AAA';
ctx.textAlign="center";
$(Trends.datasets).each(function(idx,dataset){
$(dataset.points).each(function(pdx,pointinfo){
// First dataset is shifted off the scale line.
// Don't write to the canvas for the null placeholder.
if ( pointinfo.value !== null ) {
ctx.fillText(pointinfo.value,pointinfo.x,pointinfo.y - 15);
}
});
});
}
var data = {
labels: ["",11.3]
}
]
};
var options = {
responsive: true,scaleFontSize: 18,onAnimationProgress: function() { drawDatasetPointsLabels() },onAnimationComplete: function() { drawDatasetPointsLabels() }
}
var ctx = $("#myChart").get(0).getContext("2d");
var Trends = new Chart(ctx).Line(data,options);
function drawDatasetPointsLabels() {
ctx.font = '.9rem "Gotham Book",dataset){
// First dataset is shifted off the scale line.
// Don't write to the canvas for the null placeholder.
$(dataset.points).each(function(pdx,pointinfo){
if ( pointinfo.value !== null ) {
ctx.fillText(pointinfo.value,pointinfo.y - 15);
}
});
});
}
这是jsfiddle：http://jsfiddle.net/s9eannLh上最初的有问题的版本
[更新链接]
以下是jsfiddle：https://jsfiddle.net/s9eannLh/82/的更新解决方案
谢谢大家！
