图表js-甜甜圈总是显示工具提示吗？

Question

当使用图表时。js库，我可以添加多个甜甜圈在我的页面上没有问题。

http://www.chartjs.org/docs/#doughnut-饼图

但是我找不到一种方法总是显示工具提示——不仅仅是当鼠标悬停在甜甜圈上时。有人知道这是否可能吗？

Answer 1

我对Kapi的方法进行了扩展，因此当您将鼠标悬停在它上面时，仍然可以保留默认功能，如颜色更改，而当您将鼠标悬停在某个部分上时，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);
});

Answer 2

您可以通过编写自己的插件来实现这一点，该插件支持ChartJS版本

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

// 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
  }
});

html lang-html prettyprint-override"><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>

Answer 3

我今天也遇到了同样的问题，通过在animationcomplte和tooltipevents上添加选项，我很容易就解决了这个问题。

OnAnitationComplete调用该方法以像悬停事件一样显示工具提示。通常在ToolTipeEvents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:(http://www.chartjs.org/docs/#doughnut-饼图）。

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);  

超文本标记语言：

<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"
    }
]

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

jsiddle条/线：http://jsfiddle.net/5gyfykka/14/