想做图表？Android优秀图表库MPAndroidChart
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前言
在项目当中很多时候要对数据进行分析就要用到图表，在gitHub上有很多优秀的图表开源库，今天给大家分享的就是MPAndroidChart中的柱状图。简单介绍一下MPAndroidChart：他可以实现图表的拖动，3D，局部查看，数据动态展示等功能。
官方源码地址：github.com/PhilJay/MPA…
废话就不多说啦，先给看大家看看效果图哟
操作步骤
第一步：需要将依赖的库添加到你的项目中
implementation 'com.github.PhilJay:MPAndroidChart:v3.1.0-alpha'
implementation 'com.google.android.material:material:1.0.0'
第二步：xml中
<com.github.mikephil.charting.charts.BarChart
android:id="@+id/chart1"
android:layout_width="match_parent"
android:layout_height="300dp"
/>
第三步：ValueFormatter.java
/**
* Class to format all values before they are drawn as labels.
*/
public abstract class ValueFormatter implements IAxisValueFormatter, IValueFormatter {
/**
* <b>DO NOT USE</b>, only for backwards compatibility and will be removed in future versions.
*
* @param value the value to be formatted
* @param axis the axis the value belongs to
* @return formatted string label
*/
@Override
@Deprecated
public String getFormattedValue(float value, AxisBase axis) {
return getFormattedValue(value);
}
/**
* <b>DO NOT USE</b>, only for backwards compatibility and will be removed in future versions.
* @param value the value to be formatted
* @param entry the entry the value belongs to - in e.g. BarChart, this is of class BarEntry
* @param dataSetIndex the index of the DataSet the entry in focus belongs to
* @param viewPortHandler provides information about the current chart state (scale, translation, ...)
* @return formatted string label
*/
@Override
@Deprecated
public String getFormattedValue(float value, Entry entry, int dataSetIndex, ViewPortHandler viewPortHandler) {
return getFormattedValue(value);
}
/**
* Called when drawing any label, used to change numbers into formatted strings.
*
* @param value float to be formatted
* @return formatted string label
*/
public String getFormattedValue(float value) {
return String.valueOf(value);
}
/**
* Used to draw axis labels, calls {@link #getFormattedValue(float)} by default.
*
* @param value float to be formatted
* @param axis axis being labeled
* @return formatted string label
*/
public String getAxisLabel(float value, AxisBase axis) {
return getFormattedValue(value);
}
/**
* Used to draw bar labels, calls {@link #getFormattedValue(float)} by default.
*
* @param barEntry bar being labeled
* @return formatted string label
*/
public String getBarLabel(BarEntry barEntry) {
return getFormattedValue(barEntry.getY());
}
/**
* Used to draw stacked bar labels, calls {@link #getFormattedValue(float)} by default.
*
* @param value current value to be formatted
* @param stackedEntry stacked entry being labeled, contains all Y values
* @return formatted string label
*/
public String getBarStackedLabel(float value, BarEntry stackedEntry) {
return getFormattedValue(value);
}
/**
* Used to draw line and scatter labels, calls {@link #getFormattedValue(float)} by default.
*
* @param entry point being labeled, contains X value
* @return formatted string label
*/
public String getPointLabel(Entry entry) {
return getFormattedValue(entry.getY());
}
/**
* Used to draw pie value labels, calls {@link #getFormattedValue(float)} by default.
*
* @param value float to be formatted, may have been converted to percentage
* @param pieEntry slice being labeled, contains original, non-percentage Y value
* @return formatted string label
*/
public String getPieLabel(float value, PieEntry pieEntry) {
return getFormattedValue(value);
}
/**
* Used to draw radar value labels, calls {@link #getFormattedValue(float)} by default.
*
* @param radarEntry entry being labeled
* @return formatted string label
*/
public String getRadarLabel(RadarEntry radarEntry) {
return getFormattedValue(radarEntry.getY());
}
/**
* Used to draw bubble size labels, calls {@link #getFormattedValue(float)} by default.
*
* @param bubbleEntry bubble being labeled, also contains X and Y values
* @return formatted string label
*/
public String getBubbleLabel(BubbleEntry bubbleEntry) {
return getFormattedValue(bubbleEntry.getSize());
}
/**
* Used to draw high labels, calls {@link #getFormattedValue(float)} by default.
*
* @param candleEntry candlestick being labeled
* @return formatted string label
*/
public String getCandleLabel(CandleEntry candleEntry) {
return getFormattedValue(candleEntry.getHigh());
}
}
第四步：MyValueFormatter
public class MyValueFormatter extends ValueFormatter{
private final DecimalFormat mFormat;
private String suffix;
public MyValueFormatter(String suffix) {
mFormat = new DecimalFormat("0000");
this.suffix = suffix;
}
@Override
public String getFormattedValue(float value) {
return mFormat.format(value) + suffix;
}
@Override
public String getAxisLabel(float value, AxisBase axis) {
if (axis instanceof XAxis) {
return mFormat.format(value);
} else if (value > 0) {
return mFormat.format(value) + suffix;
} else {
return mFormat.format(value);
}
}
}
第五步：MainAcyivity
package detongs.hbqianze.him.linechart;
import android.os.Bundle;
import android.util.Log;
import android.view.WindowManager;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;
import com.github.mikephil.charting.charts.BarChart;
import com.github.mikephil.charting.components.XAxis;
import com.github.mikephil.charting.components.YAxis;
import com.github.mikephil.charting.data.BarData;
import com.github.mikephil.charting.data.BarDataSet;
import com.github.mikephil.charting.data.BarEntry;
import com.github.mikephil.charting.interfaces.datasets.IBarDataSet;
import com.github.mikephil.charting.interfaces.datasets.IDataSet;
import com.github.mikephil.charting.utils.ColorTemplate;
import java.util.ArrayList;
import detongs.hbqianze.him.linechart.chart.MyValueFormatter;
import detongs.hbqianze.him.linechart.chart.ValueFormatter;
public class MainActivity extends AppCompatActivity {
private BarChart chart;
private TextView te_cache;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
chart = findViewById(R.id.chart1);
te_cache = findViewById(R.id.te_cache);
chart.getDescription().setEnabled(false);
//设置最大值条目，超出之后不会有值
chart.setMaxVisibleValueCount(60);
//分别在x轴和y轴上进行缩放
chart.setPinchZoom(true);
//设置剩余统计图的阴影
chart.setDrawBarShadow(false);
//设置网格布局
chart.setDrawGridBackground(true);
//通过自定义一个x轴标签来实现2,015 有分割符符bug
ValueFormatter custom = new MyValueFormatter(" ");
//获取x轴线
XAxis xAxis = chart.getXAxis();
//设置x轴的显示位置
xAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
//设置网格布局
xAxis.setDrawGridLines(true);
//图表将避免第一个和最后一个标签条目被减掉在图表或屏幕的边缘
xAxis.setAvoidFirstLastClipping(false);
//绘制标签 指x轴上的对应数值 默认true
xAxis.setDrawLabels(true);
xAxis.setValueFormatter(custom);
//缩放后x 轴数据重叠问题
xAxis.setGranularityEnabled(true);
//获取右边y标签
YAxis axisRight = chart.getAxisRight();
axisRight.setStartAtZero(true);
//获取左边y轴的标签
YAxis axisLeft = chart.getAxisLeft();
//设置Y轴数值 从零开始
axisLeft.setStartAtZero(true);
chart.getAxisLeft().setDrawGridLines(false);
//设置动画时间
chart.animateXY(600,600);
chart.getLegend().setEnabled(true);
getData();
//设置柱形统计图上的值
chart.getData().setValueTextSize(10);
for (IDataSet set : chart.getData().getDataSets()){
set.setDrawValues(!set.isDrawValuesEnabled());
}
}
public void getData(){
ArrayList<BarEntry> values = new ArrayList<>();
Float aFloat = Float.valueOf("2015");
Log.v("xue","aFloat+++++"+aFloat);
BarEntry barEntry = new BarEntry(aFloat,Float.valueOf("100"));
BarEntry barEntry1 = new BarEntry(Float.valueOf("2016"),Float.valueOf("210"));
BarEntry barEntry2 = new BarEntry(Float.valueOf("2017"),Float.valueOf("300"));
BarEntry barEntry3 = new BarEntry(Float.valueOf("2018"),Float.valueOf("450"));
BarEntry barEntry4 = new BarEntry(Float.valueOf("2019"),Float.valueOf("300"));
BarEntry barEntry5 = new BarEntry(Float.valueOf("2020"),Float.valueOf("650"));
BarEntry barEntry6 = new BarEntry(Float.valueOf("2021"),Float.valueOf("740"));
values.add(barEntry);
values.add(barEntry1);
values.add(barEntry2);
values.add(barEntry3);
values.add(barEntry4);
values.add(barEntry5);
values.add(barEntry6);
BarDataSet set1;
if (chart.getData() != null &&
chart.getData().getDataSetCount() > 0) {
set1 = (BarDataSet) chart.getData().getDataSetByIndex(0);
set1.setValues(values);
chart.getData().notifyDataChanged();
chart.notifyDataSetChanged();
} else {
set1 = new BarDataSet(values, "点折水");
set1.setColors(ColorTemplate.VORDIPLOM_COLORS);
set1.setDrawValues(false);
ArrayList<IBarDataSet> dataSets = new ArrayList<>();
dataSets.add(set1);
BarData data = new BarData(dataSets);
chart.setData(data);
chart.setFitBars(true);
}
//绘制图表
chart.invalidate();
}
}
