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在 android开源图表库MPAndroidChart文档翻译（上） 中，介绍了mpandroidchart的创建，回调方法，还有轴。这篇文章继续翻译剩余内容。文档内容比较多，这是中篇。最后的内容在下篇做翻译。

六、设置数据

要给图表设置数据，调用的方法为

  public void setData(ChartData data) { ... }

 // this is just one of many constructors
    public LineData(ArrayList<String> xVals, ArrayList<ILineDataSet> sets) { ... }

例如，你可能想在LineChart中想展示两家公司一年的季度收入。这种情况，建议使用两个不同的LineDataSet对象,每个包含四个值（一年四个季度），使用ArrayList描述X轴上的标签，只需要简单数据源 "1.Q", "2.Q", "3.Q", "4.Q"。
当然，使用一个LineDataSet对象，包含这两个公司的8个值也是可以的。
初始化LineDataSet对象

 public LineDataSet(ArrayList<Entry> yVals, String label) { ... }

Entry类型的ArrayList包含了表中的所有值，一个Entry对象包含了x轴的位置，和它对应的值。

    public Entry(float val, int xIndex) { ... }

    ArrayList<Entry> valsComp1 = new ArrayList<Entry>();
    ArrayList<Entry> valsComp2 = new ArrayList<Entry>();

   Entry c1e1 = new Entry(100.000f, 0); // 0 == quarter 1
    valsComp1.add(c1e1);
    Entry c1e2 = new Entry(50.000f, 1); // 1 == quarter 2 ...
    valsComp1.add(c1e2);
    // and so on ...

    Entry c2e1 = new Entry(120.000f, 0); // 0 == quarter 1
    valsComp2.add(c2e1);
    Entry c2e2 = new Entry(110.000f, 1); // 1 == quarter 2 ...
    valsComp2.add(c2e2);
    //...

 LineDataSet setComp1 = new LineDataSet(valsComp1, "Company 1");
 setComp1.setAxisDependency(AxisDependency.LEFT);
 LineDataSet setComp2 = new LineDataSet(valsComp2, "Company 2");
 setComp2.setAxisDependency(AxisDependency.LEFT);

  // use the interface ILineDataSet
    ArrayList<ILineDataSet> dataSets = new ArrayList<ILineDataSet>();
    dataSets.add(setComp1);
    dataSets.add(setComp2);

    ArrayList<String> xVals = new ArrayList<String>();
    xVals.add("1.Q"); xVals.add("2.Q"); xVals.add("3.Q"); xVals.add("4.Q"); 

    LineData data = new LineData(xVals, dataSets);
    mLineChart.setData(data);
    mLineChart.invalidate(); // refresh

七、设置颜色

我们希望用红色代表一个公司的数据
用绿色代表另一个公司数据。
代码为

 LineDataSet setComp1 = new LineDataSet(valsComp1, "Company 1");
  // sets colors for the dataset, resolution of the resource name to a "real" color is done internally
  setComp1.setColors(new int[] { R.color.red1, R.color.red2, R.color.red3, R.color.red4 }, Context);

  LineDataSet setComp2 = new LineDataSet(valsComp2, "Company 2");
  setComp2.setColors(new int[] { R.color.green1, R.color.green2, R.color.green3, R.color.green4 }, Context);

LineDataSet set = new LineDataSet(...);
set.setColors(ColorTemplate.VORDIPLOM_COLORS);

八、值的格式化接口ValueFormatter

从1.6.2版本可用，在2.1.4版本做出修改。
ValueFormatter接口可以用来指定绘制的格式

ublic class MyValueFormatter implements ValueFormatter {

    private DecimalFormat mFormat;

    public MyValueFormatter() {
        mFormat = new DecimalFormat("###,###,##0.0"); // use one decimal
    }

    @Override
    public String getFormattedValue(float value, Entry entry, int dataSetIndex, ViewPortHandler viewPortHandler) {
        // write your logic here
        return mFormat.format(value) + " $"; // e.g. append a dollar-sign
    }
}

// usage on whole data object
lineData.setValueFormatter(new MyValueFormatter());

// usage on individual dataset object
lineDataSet.setValueFormatter(new MyValueFormatter());

LargeValueFormatter: 用于较大值得转换，如1000转换成1k,不支持小数点。
PercentFormatter:使用百分号，在饼状图中特别有用
StackedValueFormatter: 在 BarChart中使用. 它允许指定所有的堆栈值是否应绘制，或者是最高值

九、X轴上的格式化接口XAxisValueFormatter

public class MyCustomXAxisValueFormatter implements XAxisValueFormatter {

    @Override
    public String getXValue(String original, int index, ViewPortHandler viewPortHandler) {
        // original is the original value to use, x-index is the index in your x-values array
        // implement your logic here ...
        return ...;
    }
}

// usage on XAxis, get axis instance:
XAxis xAxis = chart.getXAxis();

// set the formatter
xAxis.setValueFormatter(new MyCustomXAxisValueFormatter());

自定义格式转换MyCustomXValueFormatter

十、Y轴上的格式化接口YAxisValueFormatter

public class MyYAxisValueFormatter implements YAxisValueFormatter {

    private DecimalFormat mFormat;

    public MyYAxisValueFormatter () {
        mFormat = new DecimalFormat("###,###,##0.0"); // use one decimal
    }

    @Override
    public String getFormattedValue(float value, YAxis yAxis) {
        // write your logic here
        // access the YAxis object to get more information
        return mFormat.format(value) + " $"; // e.g. append a dollar-sign
    }
}

// get an instance of the YAxis (e.g. left axis)
YAxis leftAxis = chart.getAxisLeft();
leftAxis.setValueFormatter(new MyYAxisValueFormatter());

十一、具体图表的设置

Line-, Bar-, Scatter-, Candle- & BubbleChart

折线图，条形表，散点图，K线图，气泡图

setAutoScaleMinMaxEnabled(boolean enabled): 指示是否启用在y轴自动缩放。如果启用，当视角变换时，Y轴自动调整到和当前的X轴范围适应的最小值，默认值false
setKeepPositionOnRotation(boolean enabled): 伸缩之后是否能还原到原来的位置. 默认值false

BarChart条形图

PieChart饼状图

十二、图例

Legend legend = chart.getLegend();

setEnabled(boolean enabled)

Legend l = chart.getLegend();
    l.setFormSize(10f); // set the size of the legend forms/shapes
    l.setForm(LegendForm.CIRCLE); // set what type of form/shape should be used
    l.setPosition(LegendPosition.BELOW_CHART_LEFT);
    l.setTypeface(...);
    l.setTextSize(12f);
    l.setTextColor(Color.BLACK);
    l.setXEntrySpace(5f); // set the space between the legend entries on the x-axis
    l.setYEntrySpace(5f); // set the space between the legend entries on the y-axis

    // set custom labels and colors
    l.setCustom(ColorTemplate.VORDIPLOM_COLORS, new String[] { "Set1", "Set2", "Set3", "Set4", "Set5" });

    // and many more...

 // EXAMPLE 1
 // add entries to the "data" object
 exampleData.addEntry(...);
 chart.notifyDataSetChanged(); // let the chart know it's data changed
 chart.invalidate(); // refresh

 // EXAMPLE 2
 // add entries to "dataSet" object
 dataSet.addEntry(...);
 exampleData.notifyDataChanged(); // let the data know a dataSet changed
 chart.notifyDataSetChanged(); // let the chart know it's data changed
 chart.invalidate(); // refresh

示例

DynamicalAddingActivity
RealtimeDataActivity

十四、修改视图窗口

这个库有多种修改视图方法，需要注意的是，这些方法只适用于LineChart, BarChart, ScatterChart and CandleStickChart。
下面提到的方法是Chart类提供的方法，另一种方法是通过ViewPortHandler直接访问，但是这种方法只推荐熟悉API的高级用户使用。

限制可见性
setVisibleXRangeMaximum(float maxXRange): 设置X轴上可见区域的最大值。
setVisibleXRangeMinimum(float minXRange):设置X轴上可见的最小值，限制最小缩放。
setVisibleYRangeMaximum(float maxYRange, AxisDependency axis): 设置Y轴可见的最大值。
setViewPortOffsets(float left, float top, float right, float bottom): 设置视图偏移量，影响自动偏移量，使用resetViewPortOffsets()方法撤销操作
etExtraOffsets(float left, float top, float right, float bottom):设置额外的偏移量，这样做不会改变自动偏移量

移动视图
fitScreen(): 充满边界
moveViewToX(float xValue):移动到X轴固定位置
moveViewTo(float xValue, float yValue, AxisDependency axis): 移动到X,Y轴固定位置
移动动画设置
moveViewToAnimated(float xValue, float yValue, AxisDependency axis, long duration)
centerViewToAnimated(float xValue, float yValue, AxisDependency axis, long duration)
注意：所有的moveViewTo方法都会自动刷新视图，不需要调用invalidate()方法
缩放
zoomIn()
zoomOut():
zoom(float scaleX, float scaleY, float x, float y): 
zoom(float scaleX, float scaleY, float xValue, float yValue, AxisDependency axis): 
缩放动画
zoomAndCenterAnimated(float scaleX, float scaleY, float xValue, float yValue, AxisDependency axis, long duration):

chart.setData(...); // first set data

// now modify viewport
chart.setVisibleXRangeMaximum(20); // allow 20 values to be displayed at once on the x-axis, not more
chart.moveViewToX(10); // set the left edge of the chart to x-index 10
// moveViewToX(...) also calls invalidate()

十五、动画设置

mChart.animateX(3000); // animate horizontal 3000 milliseconds
// or:
mChart.animateY(3000); // animate vertical 3000 milliseconds
// or:
mChart.animateXY(3000, 3000); // animate horizontal and vertical 3000 milliseconds

public enum EasingOption {
      Linear,
      EaseInQuad,
      EaseOutQuad,
      EaseInOutQuad,
      EaseInCubic,
      EaseOutCubic,
      EaseInOutCubic,
      EaseInQuart,
      EaseOutQuart,
      EaseInOutQuart,
      EaseInSine,
      EaseOutSine,
      EaseInOutSine,
      EaseInExpo,
      EaseOutExpo,
      EaseInOutExpo,
      EaseInCirc,
      EaseOutCirc,
      EaseInOutCirc,
      EaseInElastic,
      EaseOutElastic,
      EaseInOutElastic,
      EaseInBack,
      EaseOutBack,
      EaseInOutBack,
      EaseInBounce,
      EaseOutBounce,
      EaseInOutBounce,
  }

 public void animateY(int durationmillis, EasingFunction function); 

 /**
  * Interface for creating custom made easing functions. 
  */
  public interface EasingFunction {
     /**
      * Called everytime the animation is updated.
      * @param input - the time passed since the animation started (value between 0 and 1)
      */
      public float getInterpolation(float input);
  }

public class CustomMarkerView extends MarkerView {

    private TextView tvContent;

    public CustomMarkerView (Context context, int layoutResource) {
        super(context, layoutResource);
        // this markerview only displays a textview
        tvContent = (TextView) findViewById(R.id.tvContent);
    }

    // callbacks everytime the MarkerView is redrawn, can be used to update the
    // content (user-interface)
    @Override
    public void refreshContent(Entry e, Highlight highlight) {
        tvContent.setText("" + e.getVal()); // set the entry-value as the display text
    }

    @Override
    public int getXOffset(float xpos) {
        // this will center the marker-view horizontally
        return -(getWidth() / 2);
    }

    @Override
    public int getYOffset(float ypos) {
        // this will cause the marker-view to be above the selected value
        return -getHeight();
    }
}

CustomMarkerView mv = new CustomMarkerView(Context, R.layout.custom_marker_view_layout);

// set the marker to the chart
chart.setMarkerView(mv);

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android开源图表库MPAndroidChart文档翻译（中）

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原文地址：http://blog.csdn.net/robertcpp/article/details/51622083