无法获取 angular 堆叠条形图中图表单击的系列值

Question

 <canvas class="chart chart-bar" chart-data="data" chart-labels="labels"
                  chart-options="options" chart-series="series" chart-click="onclick"></canvas>

'use strict';

var app = angular.module('examples', ['chart.js', 'ui.bootstrap']);

app.controller('StackedBarCtrl', ['$scope', function ($scope) {
    $scope.labels = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'];
    $scope.type = 'StackedBar';
    $scope.series = ['2015', '2016'];
    $scope.options = {
      scales: {
        xAxes: [{
          stacked: true,
        }],
        yAxes: [{
          stacked: true
        }]
      }
    };

    $scope.onclick = function(points,evt)
    {
        console.log("evt "+points[0]["_modal"]["datasetLabel"]);
    }

    $scope.data = [
      [65, 59, 90, 81, 56, 55, 40],
      [28, 48, 40, 19, 96, 27, 100]
    ];
}]);

如果我点击第 28 栏，我没有获得值 2016，因为 onclick 函数中的点数组 return 每个堆栈都有 2 个对象，我无法弄清楚如何获得值 2016，因为那里没有标志指示点击了哪个栏

Answer 1

传递给您的 onclick 回调的第二个参数包含活动元素数组，其中的每个项目包含 _datasetIndex 和 _index

array[1]
[Element]
    _datasetIndex:0
    _index: 0

使用这些值你可以获得你需要的值

$scope.onclick = function(event, elems)
{
    var datasetIndex = elems[0]._datasetIndex;
    console.log("evt " + $scope.series[datasetIndex]);
}

请参考与您的问题相关的chartjs docs and this issue

更新

看起来堆叠条形图有点棘手。解决方案是使用 Chart.helpers

找到最近的点击栏

$scope.$on('chart-create', function(event, instance){
  // used to obtain chart instance
  $scope.chart = instance.chart;
});
$scope.onclick = function(elements,e)
{
  // helper function that translates an event to a position in canvas coordinates
  var pos = Chart.helpers.getRelativePosition(e, $scope.chart);

  // inRange is the function on the chart element that is used for hit testing
  var intersect = elements.find(function(element) {
    return element.inRange(pos.x, pos.y);
  });
  if(intersect){
    alert('You clicked ' + $scope.labels[intersect._index] + ' ' + $scope.series[intersect._datasetIndex]);    
  }
}

这是工作plunkr

无法获取 angular 堆叠条形图中图表单击的系列值

Unable to get series vale for chart-click in angular stacked bar graph

angularjs

angular-chart