如何使标签在角度图表中可点击

Question

我正在尝试向由 angular-chart 呈现的图表的标签添加一个点击处理程序。

有没有办法添加特定的事件处理程序或使用现有的图表点击指令？

目前，图表单击指令仅返回 MouseEvent 对象。

阅读文档后，我找不到答案。

Answer 1

您可以使用getPointsAtEvent事件来检测图形上最近的点，并检索其关联的标签。 问题是您无法直接检测标签元素上的点击，因为它在<canvas>元素中绘制为文本。

演示：

 angular.module( 'app', ['tc.chartjs']); angular.module( 'app' ) .controller( 'AppController', function( $scope ) { $scope.chart; $scope.chartClick = function( event ) { var pointsClicked = $scope.chart.getPointsAtEvent(event); if (!pointsClicked || pointsClicked.length == 0) return; if (pointsClicked[0].label) $scope.label = 'You clicked on ' + pointsClicked[0].label; }; // Chart.js Data $scope.data = { labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'], datasets: [ { label: 'My First dataset', fillColor: 'rgba(220,220,220,0.2)', strokeColor: 'rgba(220,220,220,1)', pointColor: 'rgba(220,220,220,1)', pointStrokeColor: '#fff', pointHighlightFill: '#fff', pointHighlightStroke: 'rgba(220,220,220,1)', data: [65, 59, 80, 81, 56, 55, 40] } ] }; // Chart.js Options $scope.options = { // Sets the chart to be responsive responsive: true }; }); /** * tc-angular-chartjs - v1.0.9 - 2014-10-14 * Copyright (c) 2014 Carl Craig <carlcraig@3c-studios.com> * Dual licensed with the Apache-2.0 or MIT license. */ !function(){"use strict";function a(a){return new a}function b(a){return new a("line")}function c(a){return new a("bar")}function d(a){return new a("radar")}function e(a){return new a("polararea")}function f(a){return new a("pie")}function g(a){return new a("doughnut")}function h(){return function(a){function b(b,d,e){var f,g=d[0].getContext("2d"),h=new Chart(g),i=!1,j=!1,k=!1,l=null;for(var m in e)"chartLegend"===m?i=!0:"chart"===m?k=!0:"autoLegend"===m&&(j=!0);b.$watch("data",function(e){if(e){if(f&&f.destroy(),a)f=h[c(a)](b.data,b.options);else{if(!b.type)throw"Error creating chart: Chart type required.";f=h[c(b.type)](b.data,b.options)}i&&(b.legend=f.generateLegend()),j&&(l&&l.remove(),angular.element(d[0]).after(f.generateLegend()),l=angular.element(d[0]).next()),k&&(b.chart=f)}},!0)}function c(a){var b=a.toLowerCase();switch(b){case"line":return"Line";case"bar":return"Bar";case"radar":return"Radar";case"polararea":return"PolarArea";case"pie":return"Pie";case"doughnut":return"Doughnut";default:return a}}var d={restrict:"A",scope:{data:"=chartData",options:"=chartOptions",type:"@chartType",legend:"=chartLegend",chart:"=chart"},link:b};return d}}function i(){function a(a,b){a.$watch("legend",function(a){a&&b.html(a)},!0)}var b={restrict:"A",scope:{legend:"=chartLegend"},link:a};return b}angular.module("tc.chartjs",[]).directive("tcChartjs",a).directive("tcChartjsLine",b).directive("tcChartjsBar",c).directive("tcChartjsRadar",d).directive("tcChartjsPolararea",e).directive("tcChartjsPie",f).directive("tcChartjsDoughnut",g).directive("tcChartjsLegend",i).factory("TcChartjsFactory",h),a.$inject=["TcChartjsFactory"],b.$inject=["TcChartjsFactory"],c.$inject=["TcChartjsFactory"],d.$inject=["TcChartjsFactory"],e.$inject=["TcChartjsFactory"],f.$inject=["TcChartjsFactory"],g.$inject=["TcChartjsFactory"]}(); angular.bootstrap( document, [ 'app' ]);

 <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.14/angular.min.js"></script> <script src="http://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.0.1-beta.2/Chart.min.js"></script> <div ng-controller="AppController"> <canvas tc-chartjs-line chart-options="options" chart-data="data" auto-legend ng-click="chartClick($event)" chart="chart"></canvas> <h3 ng-bind="label"></h3> </div>