图表库MPAndroidChart简介

介绍

A simple charting library for Android, supporting line-, bar-, scatter-, candlestick- and piecharts, as well as scaling, dragging, selecting and animations. Supporting Android 2.2 (API level 8) and upwards.

这个图表非常强大，很多属性设置起来非常方便，并且动画效果非常酷，之前用的achartengine，跟这个对比，简直low爆了，而且用起来也非常繁琐，建议大家尽早替换吧！下面以创建曲线为例作简单的讲解，其他曲线类似

github地址：https://github.com/PhilJay/MPAndroidChart

使用

• xml

  <com.github.mikephil.charting.charts.LineChart
      android:id="@+id/chart"
      android:layout_width="match_parent"
      android:layout_height="match_parent" />
  
  LineChart chart = (LineChart) findViewById(R.id.chart);
  

• code

  LineChart chart = new LineChart(Context);
  

• init data

  ArrayList<String> xVals = new ArrayList<String>();
  ArrayList<Entry> yVals = new ArrayList<Entry>();
  
  LineDataSet set1 = new LineDataSet(yVals, title + "曲线");
  set1.setColor(Color.RED);
  set1.setCircleColor(Color.RED);
  set1.setLineWidth(2f);
  set1.setCircleSize(4f);
  set1.setDrawCircles(true);
  set1....//可以根据需求设置一系列参数，非常详细
  
  ArrayList<LineDataSet> dataSets = new ArrayList<LineDataSet>();
  dataSets.add(set1); // add the datasets 创建多个表示多根曲线
  // create a data object with the datasets
  LineData data = new LineData(xVals, dataSets);
  //最后
  chart.setData(data);
  

几点说明

1. 为了兼容低版本动画效果，此库必须导入第三方动画库nineoldandroids.jar，如果你是以jar包的形式应用并且你的项目已经引入了nineoldandroids.jar，请将项目中的nineoldandroids.jar删除，否则项目会报错

2. 可以直接调用方法将图表的截图保存到图库或者sd卡，非常方便

   saveToGallery(String title): Saves the current chart state as an image to the gallery.
   saveToPath(String title, String pathOnSD): Saves the current chart state as an image to the specified path.
   

3. 可以设置曲线展示动画方式（）

   animateX(int durationMillis): Animates the charts values on the horizontal axis, meaning that the chart will build up within the specified time from left to right.
   animateY(int durationMillis): Animates the charts values on the vertical axis, meaning that the chart will build up within the specified time from bottom to top.
   animateXY(int xDuration, int yDuration): Animates both horizontal and vertical axis, resulting in a left/right bottom/top build-up.
   

4. 可以改变图表中图例的颜色及显示位置

   Legend legend = lineChart.getLegend();
   legend.setTextColor(Color.WHITE);
   legend.setPosition(LegendPosition.BELOW_CHART_CENTER);
   

5. 可以设置图表、x轴、y轴、图例的字体

   Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/OpenSans-SemiboldItalic.ttf");
   //图表
   chart.setValueTypeface(tf);
   //x轴
   XLabels x = chart.getXLabels();
   x.setTypeface(tf);
   //y轴
   YLabels y = lineChart.getYLabels();
   y.setTypeface(tf);
   //图例
   legend.setTypeface(tf)
   

6. 可以给图表添加 Limit Lines

   LimitLine maxLine = new LimitLine(maxValue);
   maxLine.setLineWidth(4f);
   maxLine.enableDashedLine(10f, 10f, 0f);
   maxLine.setDrawValue(false);
   maxLine.setLabelPosition(LimitLabelPosition.RIGHT);
   
   LimitLine minLine = new LimitLine(minValue);
   minLine.setLineWidth(4f);
   minLine.enableDashedLine(10f, 10f, 0f);
   minLine.setDrawValue(false);
   minLine.setLabelPosition(LimitLabelPosition.RIGHT);
   
   lineData.addLimitLine(maxLine);
   lineData.addLimitLine(minLine);