我最近在使用一个安卓图表插件androidplot，看到别人很多代码都使用了匿名内部类，像这样：
_ratePlot.setRangeValueFormat(new Format() {
@Override
public StringBuffer format(Object obj, @NonNull StringBuffer toAppendTo,
@NonNull FieldPosition pos) {
double val = ((Number) obj).doubleValue();
double maxY = _ratePlot.getCalculatedMaxY().doubleValue();
if (val == 0 || maxY < finalK) {
return new DecimalFormat("0").format(val, toAppendTo, pos);
} else if (maxY < finalK * finalK) {
if (val < 10 * finalK)
return new DecimalFormat("0.0 k").format(val / (1000), toAppendTo, pos);
else
return new DecimalFormat("0 k").format(val / (1000), toAppendTo, pos);
} else {
if (val < 10 * finalK * finalK)
return new DecimalFormat("0.0 M").format(val / (finalK * finalK), toAppendTo, pos);
else
return new DecimalFormat("0 M").format(val / (finalK * finalK), toAppendTo, pos);
}
}
@Override
public Object parseObject(String source, @NonNull ParsePosition pos) {
return null;
}
});
但是我只看到了定义这个匿名内部类，没有看到在哪里调用，所以有没有大神知道怎样确定参数obj的值，也就是val到底是多少呢？
完整代码：
package net.i2p.android.router.stats;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.androidplot.xy.BarFormatter;
import com.androidplot.xy.BarRenderer;
import com.androidplot.xy.BoundaryMode;
import com.androidplot.xy.XYPlot;
import com.androidplot.xy.XYSeries;
import com.androidplot.xy.XYStepMode;
import net.i2p.android.router.I2PFragmentBase;
import net.i2p.android.router.R;
import net.i2p.android.router.service.StatSummarizer;
import net.i2p.android.router.service.SummaryListener;
import net.i2p.android.router.util.Util;
import java.text.DateFormat;
import java.text.DecimalFormat;
import java.text.FieldPosition;
import java.text.Format;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Observable;
import java.util.Observer;
public class RateGraphFragment extends I2PFragmentBase {
// redraws a plot whenever an update is received:
private class MyPlotUpdater implements Observer {
public void update(Observable o, Object arg) {
Util.d("Redrawing plot");
updatePlot();
}
}
public static final String RATE_NAME = "rate_name";
public static final String RATE_PERIOD = "rate_period";
private Handler _handler;
private SetupTask _setupTask;
private SummaryListener _listener;
private XYPlot _ratePlot;
private MyPlotUpdater _plotUpdater;
private int _k;
public static RateGraphFragment newInstance(String name, long period) {
RateGraphFragment f = new RateGraphFragment();
Bundle args = new Bundle();
args.putString(RATE_NAME, name);
args.putLong(RATE_PERIOD, period);
f.setArguments(args);
return f;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
_handler = new Handler();
_setupTask = new SetupTask();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_graph, container, false);
_ratePlot = (XYPlot) v.findViewById(R.id.rate_stat_plot);
return v;
}
@Override
public void onStart() {
super.onStart();
_handler.removeCallbacks(_setupTask);
_handler.postDelayed(_setupTask, 100);
}
@Override
public void onStop() {
super.onStop();
if (_listener != null && _plotUpdater != null) {
Util.d("Removing plot updater from listener");
_listener.removeObserver(_plotUpdater);
}
_handler.removeCallbacks(_setupTask);
}
private class SetupTask implements Runnable {
public void run() {
String rateName = getArguments().getString(RATE_NAME);
long period = getArguments().getLong(RATE_PERIOD);
_k = 1000;
if (rateName.startsWith("bw.") || rateName.contains("Size") || rateName.contains("Bps") || rateName.contains("memory"))
_k = 1024;
Util.d("Setting up " + rateName + "." + period);
if (StatSummarizer.instance() == null) {
Util.d("StatSummarizer is null, delaying setup");
_handler.postDelayed(this, 1000);
return;
}
_listener = StatSummarizer.instance().getListener(rateName, period);
if (_listener == null) {
Util.d("Listener is null, delaying setup");
_handler.postDelayed(this, 1000);
return;
}
XYSeries rateSeries = _listener.getSeries();
_plotUpdater = new MyPlotUpdater();
_ratePlot.addSeries(rateSeries, new BarFormatter(Color.argb(200, 0, 80, 0), Color.argb(200, 0, 80, 0)));
_ratePlot.calculateMinMaxVals();
long maxX = _ratePlot.getCalculatedMaxX().longValue();
Util.d("Adding plot updater to listener");
_listener.addObserver(_plotUpdater);
// Only one line, so hide the legend
_ratePlot.getLegendWidget().setVisible(false);
BarRenderer renderer = (BarRenderer) _ratePlot.getRenderer(BarRenderer.class);
renderer.setBarWidthStyle(BarRenderer.BarWidthStyle.VARIABLE_WIDTH);
renderer.setBarGap(0);
_ratePlot.setDomainUpperBoundary(maxX, BoundaryMode.GROW);
_ratePlot.setDomainStep(XYStepMode.INCREMENT_BY_VAL, 15 * 60 * 1000);
_ratePlot.setTicksPerDomainLabel(4);
_ratePlot.setRangeLowerBoundary(0, BoundaryMode.FIXED);
_ratePlot.setTicksPerRangeLabel(5);
_ratePlot.setDomainValueFormat(new Format() {
private DateFormat dateFormat = SimpleDateFormat.getTimeInstance(DateFormat.SHORT);
@Override
public StringBuffer format(Object obj, @NonNull StringBuffer toAppendTo,
@NonNull FieldPosition pos) {
long when = ((Number) obj).longValue();
Date date = new Date(when);
return dateFormat.format(date, toAppendTo, pos);
}
@Override
public Object parseObject(String s, @NonNull ParsePosition parsePosition) {
return null;
}
});
final int finalK = _k;
_ratePlot.setRangeValueFormat(new Format() {
@Override
public StringBuffer format(Object obj, @NonNull StringBuffer toAppendTo,
@NonNull FieldPosition pos) {
double val = ((Number) obj).doubleValue();
double maxY = _ratePlot.getCalculatedMaxY().doubleValue();
if (val == 0 || maxY < finalK) {
return new DecimalFormat("0").format(val, toAppendTo, pos);
} else if (maxY < finalK * finalK) {
if (val < 10 * finalK)
return new DecimalFormat("0.0 k").format(val / (1000), toAppendTo, pos);
else
return new DecimalFormat("0 k").format(val / (1000), toAppendTo, pos);
} else {
if (val < 10 * finalK * finalK)
return new DecimalFormat("0.0 M").format(val / (finalK * finalK), toAppendTo, pos);
else
return new DecimalFormat("0 M").format(val / (finalK * finalK), toAppendTo, pos);
}
}
@Override
public Object parseObject(String source, @NonNull ParsePosition pos) {
return null;
}
});
Util.d("Redrawing plot");
updatePlot();
}
}
private void updatePlot() {
_ratePlot.calculateMinMaxVals();
double maxY = _ratePlot.getCalculatedMaxY().doubleValue();
_ratePlot.setRangeStep(XYStepMode.INCREMENT_BY_VAL, getRangeStep(maxY, _k));
_ratePlot.redraw();
}
private double getRangeStep(double maxY, int k) {
if (maxY >= k * k)
return getRangeStepForScale(maxY, k * k);
else if (maxY >= k)
return getRangeStepForScale(maxY, k);
else
return getRangeStepForScale(maxY, 1);
}
private double getRangeStepForScale(double maxY, int scale) {
if (maxY >= 400 * scale)
return 40 * scale;
else if (maxY >= 200 * scale)
return 20 * scale;
else if (maxY >= 100 * scale)
return 10 * scale;
else if (maxY >= 40 * scale)
return 4 * scale;
else if (maxY >= 20 * scale)
return 2 * scale;
else if (maxY >= 10 * scale)
return scale;
else if (maxY >= 4 * scale)
return 0.4 * scale;
else if (maxY >= 2 * scale)
return 0.2 * scale;
else
return 0.1 * scale;
}
}
