AngularJS集成HighCharts动态绘制CPU和内存变化曲线

调研了下动态曲线绘制的开源项目，HighCharts应用在AngularJS上相对容易使用和集成，来看下在AngularJS上集成HighCharts的StockChart图表，实现动态绘制Android内存和CPU的变化曲线。

一、实现效果

先看下HightCharts CPU和内存图表显示实现效果，图表左上角可以选择显示的区间范围，1分钟、5分钟或显示全部，截图显示的是全部数据，底部栏可以拖动查看不同区间数据。

二、HighCharts集成

先到HighCharts下载中心下载对应的资源，这边下载的是Highcharts-Stock-8.1.2，Highcharts-Stock下载之后就不用下载Highcharts资源，Highcharts-Stock里面已经包含，也可以直接使用CDN 文件而不用下载：

// Highcharts
<script src="http://cdn.highcharts.com.cn/highcharts/8.1.2/highcharts.js"></script>
// Highcharts Stock
<script src="http://cdn.highcharts.com.cn/highstock/8.1.2/highstock.js"></script>
// Highcharts Maps
<script src="http://cdn.highcharts.com.cn/highmaps/8.1.2/highmaps.js"></script>
// Highcharts Gantt
<script src="http://cdn.highcharts.com.cn/gantt/8.1.2/highcharts-gantt.js"></script>

还可以通过 NPM 安装：

npm install highcharts --save

或者通过 Bower 安装：

bower install highcharts --save

在Highcharts-Stock-8.1.2下载完成之后，把Highcharts-Stock-8.1.2/code/highstock.js文件拷贝放到工程目录下，添加highstock.js引用声明，之后就可以在工程里面使用Highcharts：

script(src='*****/*****/highstock.js')

三、Highcharts-Stock绘制CPU曲线

直接上代码，先看下CPU图表的参数初始化：

前端界面：

div(id='cpu')

JS文件，renderTo参数就是指定前端界面展示的控件id ：

var chartCpuOptions = {
  chart: {
    renderTo: 'cpu'
  },
  xAxis: [{
    // currentDateIndicator: true,
    min: new Date().getTime(),
    max: new Date().getTime() + 24 * 60 * 60 * 1000
  }],
  rangeSelector: {
    buttons: [{
      count: 1,
      type: 'minute',
      text: '1M'
    }, {
      count: 5,
      type: 'minute',
      text: '5M'
    }, {
      type: 'all',
      text: 'All'
    }],
    inputEnabled: false,
    selected: 0
  },
  exporting: {
    enabled: true
  },
  title: {
    text: 'CPU'
  },
  series: [
    {
      name: 'Process CPU',
      data: []
    },
    {
      name: 'System CPU',
      data: []
    }
  ]
};

var chartCpu = new Highcharts.StockChart(chartCpuOptions);

xAxis图表横坐标轴参数一定要初始化，否则会报如下异常，min和max就是指定横坐标轴的最小值和最大值，xAxis的参数说明可以参考HighCharts API xAxis参数文档：

Error: <rect> attribute x: Expected length, "NaN".

rangeSelector就是图表范围选择器，这边配置1分钟、5分钟和全部显示三个类型，buttons的type参数取值可以是：”millisecond”, “second”, “minute”, “hour”, “day”, “week”, “month”, “ytd”, “all”。

exporting.enabled是否启用导出图表按钮，默认是true，但配置了之后竟然不会显示。

title.text配置图表显示的标题，也可以调整显示的位置。

series配置图表显示的数据列，name参数就是鼠标移动到图表曲线的时候显示的数据列悬浮提示内容。

四、Highcharts-Stock绘制内存曲线

内存曲线图表参数的初始化也类似，前端界面：

div(id='memory')

JS文件：

var chartMemoryOptions = {
  chart: {
    renderTo: 'memory'
  },
  xAxis: {
    // currentDateIndicator: true,
    min: new Date().getTime(),
    max: new Date().getTime() + 24 * 60 * 60 * 1000
  },
  rangeSelector: {
    buttons: [{
      count: 1,
      type: 'minute',
      text: '1M'
    }, {
      count: 5,
      type: 'minute',
      text: '5M'
    }, {
      type: 'all',
      text: 'All'
    }],
    inputEnabled: false,
    selected: 0
  },
  exporting: {
    enabled: true
  },
  title: {
    text: 'Memory'
  },
  series: [
    {
      name: 'Total',
      data: []
    },
    {
      name: 'Native',
      data: []
    },
    {
      name: 'Dalvik',
      data: []
    },
    {
      name: 'Sommap',
      data: []
    }
  ]
};

var chartMemory = new Highcharts.StockChart(chartMemoryOptions);

五、Highcharts图表数据刷新

1. CPU数据的刷新显示

cpulist和memorylist都是JSON结构的数据源：

//每次都设置最新的数据来更新图表
var cpuSize = cpulist.length;
var cpuTimeStamp = new Date(parseFloat(cpulist[cpuSize - 1].time)).getTime();
chartCpu.series[0].addPoint([cpuTimeStamp, parseFloat(cpulist[cpuSize - 1].processRate)]);
chartCpu.series[1].addPoint([cpuTimeStamp, parseFloat(cpulist[cpuSize - 1].systemRate)]);

//更新一次X轴的最小值和最大值，避免和初始化数据设置不一致导致图表刷新显示问题。
var hasInitCPUxAxis = false;
if(!hasInitCPUxAxis){
  hasInitCPUxAxis = true;
  chartCpu.xAxis[0].setExtremes(cpuTimeStamp - 60 * 1000, cpuTimeStamp);
}

2. Memory数据的刷新显示

var memSize = memorylist.length;
var memTimeStamp = new Date(parseFloat(memorylist[memSize - 1].time)).getTime();
chartMemory.series[0].addPoint([memTimeStamp, parseFloat((parseInt(memorylist[memSize - 1].totalPss) / 1024).toFixed(2))]);
chartMemory.series[1].addPoint([memTimeStamp, parseFloat((parseInt(memorylist[memSize - 1].nativePss) / 1024).toFixed(2))]);
chartMemory.series[2].addPoint([memTimeStamp, parseFloat((parseInt(memorylist[memSize - 1].dalvikPss) / 1024).toFixed(2))]);
chartMemory.series[3].addPoint([memTimeStamp, parseFloat((parseInt(memorylist[memSize - 1].soMmapPss) / 1024).toFixed(2))]);
var hasInitMemoryXAxis = false;
if(!hasInitMemoryXAxis){
  hasInitMemoryXAxis = true;
  chartMemory.xAxis[0].setExtremes(memTimeStamp - 60 * 1000, memTimeStamp);
}

3. 遇到的问题

这边数据更新要注意下，不能用chartCpuOptions.series[0].data.push()的方式，而要用chartMemory.series[0].addPoint([x,y]) 才有效。使用不当会输出如下异常：

Uncaught TypeError: d[w].destroyElements is not a function
    at n.generatePoints (highstock.js:5899)
    at n.e.generatePoints (highstock.js:9605)
    at n.translate (highstock.js:5939)
    at n.redraw (highstock.js:6243)
    at highstock.js:4731
    at Array.forEach (<anonymous>)
    at k.Chart.redraw (highstock.js:4730)
    at k.Chart.setSize (highstock.js:4937)
    at highstock.js:4904

另外注意添加的数据点参数不能是String类型的数据，最好加下parseInt或parseFloat的转化，控制台输出的异常提示如下：

Uncaught Error: Highcharts error #14: www.highcharts.com/errors/14/
    at k.Chart.e (highstock.js:98)
    at k.fireEvent (highstock.js:487)
    at k.error (highstock.js:110)
    at n.setData (highstock.js:5796)
    at n.g.updatedDataHandler (highstock.js:8923)
    at highstock.js:485
    at k.fireEvent (highstock.js:486)
    at highstock.js:4709
    at Array.forEach (<anonymous>)
    at k.Chart.redraw (highstock.js:4707)
    at n.addPoint (highstock.js:6658)
    at Socket.dataReceiveListener (performance-monitor.js:286)
    at Socket.Emitter.emit (index.js:131)
    at Socket.onevent (socket.js:263)
    at Socket.onpacket (socket.js:221)
    at Manager.eval (index.js:21)

关于error #14的说明如下：

String value sent to series.data, expected Number

This happens if using a string as a data point, for example in a setup like this:
series: [{
    data: ["3", "5", "1", "6"]
}]
Highcharts expects numerical data values.
The most common reason for this error this is that data is parsed from CSV or from a XML source, and the implementer forgot to run parseFloat on the parsed value.
Note: For performance reasons internal type casting is not performed, and only the first value is checked (since 2.3).