android折线图的实现

一：配置

参考上篇博客

二：模板代码

MainActivity:

public class MainActivity extends AppCompatActivity {

    private LineChart mChart;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mChart = findViewById(R.id.line_chart);
        mChart.setTouchEnabled(false);
        mChart.setDragEnabled(false);
        mChart.setScaleEnabled(false);
        mChart.setPinchZoom(false);
        mChart.setDrawGridBackground(false);
        mChart.getDescription().setEnabled(false);

        Legend legend = mChart.getLegend();
        legend.setEnabled(false);

        XAxis xAxis = mChart.getXAxis();
        xAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
        xAxis.setDrawGridLines(false);
        xAxis.setGranularity(1f);
        xAxis.setAxisMinimum(0f);
        xAxis.setAxisMaximum(6f);
        final String[] labels = new String[7];
        for (int i = 0; i <7; i++) {
            labels[i] = getPastDate(i);
        }
        xAxis.setValueFormatter(new IndexAxisValueFormatter(labels));

        YAxis yAxis = mChart.getAxisLeft();
        yAxis.setDrawGridLines(false);
        yAxis.setGranularity(1f);
        yAxis.setAxisMinimum(0);
        yAxis.setAxisMaximum(1000);
        //数据
        ArrayList<Entry> values = new ArrayList<>();
        values.add(new Entry(0, 5f));
        values.add(new Entry(1, 4f));
        values.add(new Entry(2, 6f));
        values.add(new Entry(3, 7f));
        values.add(new Entry(4, 8f));
        values.add(new Entry(5, 3f));
        values.add(new Entry(6, 2f));

        LineDataSet dataSet = new LineDataSet(values, "");
        dataSet.setLineWidth(2f);
        dataSet.setColor(Color.BLUE);
        dataSet.setCircleColor(Color.BLUE);
        dataSet.setDrawCircleHole(false);
        dataSet.setDrawValues(false);

        ArrayList<ILineDataSet> dataSets = new ArrayList<>();
        dataSets.add(dataSet);

        LineData data = new LineData(dataSets);
        mChart.setData(data);
        mChart.invalidate();
    }

    private String getPastDate(int daysAgo) {
        DateFormat dateFormat = new SimpleDateFormat("M/d", Locale.ENGLISH);
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.DAY_OF_YEAR, -daysAgo);
        Date date = calendar.getTime();
        return dateFormat.format(date);
    }
}

xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/title_textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="最近一周消费情况"
        android:textSize="18sp"
        android:textStyle="bold"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="16dp" />

    <com.github.mikephil.charting.charts.LineChart
        android:id="@+id/line_chart"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:layout_below="@id/title_textview"
        android:layout_marginTop="16dp"
        android:padding="16dp" />

</RelativeLayout>

三：具体属性

以上的代码是没有注释，理解相对不易：

详细属性参看：AndroidMPChart之LineChart详细总结 - 简书 (jianshu.com)