Chart.js - 甜甜圈总是显示工具提示？

Question

使用Chart.js库时,我可以在页面上添加多个甜甜圈而不会出现问题.

http://www.chartjs.org/docs/#doughnut-pie-chart

但我无法找到一种始终显示工具提示的方法 - 不仅仅是将鼠标悬停在甜甜圈上时.有人知道这是否可行？

Answer 1

我今天遇到了同样的问题,通过添加onAnimationComplte和tooltipevents选项很容易解决.

onAnitmationComplete调用该方法来显示像悬停事件一样的工具提示.通常,您在tooltipevents中定义事件以显示工具提示,但我们需要删除它们并传递一个空数组.

注意:( http://www.chartjs.org/docs/#doughnut-pie-chart).

使用Javascript:

var options = 
{
    tooltipTemplate: "<%= value %>",

    onAnimationComplete: function()
    {
        this.showTooltip(this.segments, true);

        //Show tooltips in bar chart (issue: multiple datasets doesnt work http://jsfiddle.net/5gyfykka/14/)
        //this.showTooltip(this.datasets[0].bars, true);

        //Show tooltips in line chart (issue: multiple datasets doesnt work http://jsfiddle.net/5gyfykka/14/)
        //this.showTooltip(this.datasets[0].points, true);  
    },

    tooltipEvents: [],

    showTooltips: true
}

var context = $('#chart').get(0).getContext('2d');
var chart = new Chart(context).Pie(data, options);  

HTML:

<div id="chartContainer">
    <canvas id="chart" width="200" height="200"></canvas>
</div>

示例数据:

var data = [
    {
        value: 300,
        color:"#F7464A",
        highlight: "#FF5A5E"
    },
    {
        value: 50,
        color: "#46BFBD",
        highlight: "#5AD3D1"
    },
    {
        value: 100,
        color: "#FDB45C",
        highlight: "#FFC870"
    }
]

JSFiddle PIE:http: //jsfiddle.net/5gyfykka/

JSFiddle BAR/LINE:http: //jsfiddle.net/5gyfykka/14/

Answer 2

您可以通过编写支持ChartJS版本> 2.1.5的自己的插件来完成此操作.

在脚本中包含以下代码:

// Show tooltips always even the stats are zero

Chart.pluginService.register({
  beforeRender: function(chart) {
    if (chart.config.options.showAllTooltips) {
      // create an array of tooltips
      // we can't use the chart tooltip because there is only one tooltip per chart
      chart.pluginTooltips = [];
      chart.config.data.datasets.forEach(function(dataset, i) {
        chart.getDatasetMeta(i).data.forEach(function(sector, j) {
          chart.pluginTooltips.push(new Chart.Tooltip({
            _chart: chart.chart,
            _chartInstance: chart,
            _data: chart.data,
            _options: chart.options.tooltips,
            _active: [sector]
          }, chart));
        });
      });

      // turn off normal tooltips
      chart.options.tooltips.enabled = false;
    }
  },
  afterDraw: function(chart, easing) {
    if (chart.config.options.showAllTooltips) {
      // we don't want the permanent tooltips to animate, so don't do anything till the animation runs atleast once
      if (!chart.allTooltipsOnce) {
        if (easing !== 1)
          return;
        chart.allTooltipsOnce = true;
      }

      // turn on tooltips
      chart.options.tooltips.enabled = true;
      Chart.helpers.each(chart.pluginTooltips, function(tooltip) {
        tooltip.initialize();
        tooltip.update();
        // we don't actually need this since we are not animating tooltips
        tooltip.pivot();
        tooltip.transition(easing).draw();
      });
      chart.options.tooltips.enabled = false;
    }
  }
});

// Show tooltips always even the stats are zero

然后,只需在要显示所有可用工具提示的任何图表的选项中使用以下行.

showAllTooltips: true

工作小提琴如下

// Show tooltips always even the stats are zero

Chart.pluginService.register({
  beforeRender: function(chart) {
    if (chart.config.options.showAllTooltips) {
      // create an array of tooltips
      // we can't use the chart tooltip because there is only one tooltip per chart
      chart.pluginTooltips = [];
      chart.config.data.datasets.forEach(function(dataset, i) {
        chart.getDatasetMeta(i).data.forEach(function(sector, j) {
          chart.pluginTooltips.push(new Chart.Tooltip({
            _chart: chart.chart,
            _chartInstance: chart,
            _data: chart.data,
            _options: chart.options.tooltips,
            _active: [sector]
          }, chart));
        });
      });

      // turn off normal tooltips
      chart.options.tooltips.enabled = false;
    }
  },
  afterDraw: function(chart, easing) {
    if (chart.config.options.showAllTooltips) {
      // we don't want the permanent tooltips to animate, so don't do anything till the animation runs atleast once
      if (!chart.allTooltipsOnce) {
        if (easing !== 1)
          return;
        chart.allTooltipsOnce = true;
      }

      // turn on tooltips
      chart.options.tooltips.enabled = true;
      Chart.helpers.each(chart.pluginTooltips, function(tooltip) {
        tooltip.initialize();
        tooltip.update();
        // we don't actually need this since we are not animating tooltips
        tooltip.pivot();
        tooltip.transition(easing).draw();
      });
      chart.options.tooltips.enabled = false;
    }
  }
});

// Show tooltips always even the stats are zero


var canvas = $('#myCanvas2').get(0).getContext('2d');
var doughnutChart = new Chart(canvas, {
  type: 'doughnut',
  data: {
    labels: [
      "Success",
      "Failure"
    ],
    datasets: [{
      data: [45, 9],
      backgroundColor: [
        "#1ABC9C",
        "#566573"
      ],
      hoverBackgroundColor: [
        "#148F77",
        "#273746"
      ]
    }]
  },
  options: {
    // In options, just use the following line to show all the tooltips
    showAllTooltips: true
  }
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.3.0/Chart.bundle.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div>
     <canvas id="myCanvas2" width="350" height="296"></canvas>
</div>

在这里工作JSFIDDLE.

Answer 3

我扩展了Kapi的方法,所以当你将鼠标悬停在它上面时,你仍然可以保持默认功能,如颜色变化,当你将鼠标悬停在一个部分上时,它将隐藏其余部分.我觉得它看起来更好.

var options =
{
    onAnimationComplete: function () {
        this.showTooltip(this.segments, true);
    },        
}

var ctx = document.getElementById("Chart").getContext("2d");
var myPieChart = new Chart(ctx).Pie(data, options);

$("#Chart").on('mouseleave', function (){
    myPieChart.showTooltip(myPieChart.segments, true);
});