First of all, please attach the address of helloCharts framework. I also learned the comprehension test by downloading that demo. Please kindly point out if there is anything I have taken into account. If you want to learn more about the framework, download the Demo and learn about it yourself.

Less nonsense, on the effect:

Step 1: Import the dependency packages

implementation 'com. Making. Lecho: hellocharts - android: v1.5.8'
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Step 2: Configure the XML file

It’s a little bit easier here, nothing to say, right

<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".LineChartActivity" >

    <lecho.lib.hellocharts.view.LineChartView
        android:id="@+id/chart"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:layout_marginBottom="100dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"></lecho.lib.hellocharts.view.LineChartView>

</androidx.constraintlayout.widget.ConstraintLayout>


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Step 3: Activity code (key)

First of all, attach all the code, the following parameters are explained in detail:

import android.graphics.Color;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;

import java.util.ArrayList;
import java.util.List;

import lecho.lib.hellocharts.animation.ChartAnimationListener;
import lecho.lib.hellocharts.gesture.ZoomType;
import lecho.lib.hellocharts.listener.LineChartOnValueSelectListener;
import lecho.lib.hellocharts.model.Axis;
import lecho.lib.hellocharts.model.AxisValue;
import lecho.lib.hellocharts.model.Line;
import lecho.lib.hellocharts.model.LineChartData;
import lecho.lib.hellocharts.model.PointValue;
import lecho.lib.hellocharts.model.ValueShape;
import lecho.lib.hellocharts.model.Viewport;
import lecho.lib.hellocharts.util.ChartUtils;
import lecho.lib.hellocharts.view.Chart;
import lecho.lib.hellocharts.view.LineChartView;

public class LineChartActivity extends AppCompatActivity {
    private LineChartView chart;
    private final int maxNumberOfLines = 4;
    private final int numberOfPoints = 6;
    private final int number=60;

    float[][] randomNumbersTab = new float[maxNumberOfLines][numberOfPoints];

    private ValueShape shape = ValueShape.CIRCLE;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_line_chart);
        chart=findViewById(R.id.chart);
        generateValues();
        generateData();

        resetViewport();
    }


    // Set the y axis from left to number
    private void resetViewport(a) {
        final Viewport v = new Viewport(chart.getMaximumViewport());
        v.bottom = 0;
        v.top = number;
        v.left = 0;
        v.right = numberOfPoints - 1;
        chart.setMaximumViewport(v);
        chart.setCurrentViewport(v);
    }

    private void generateValues(a) {
        for (int i = 0; i < maxNumberOfLines; ++i) {
            for (int j = 0; j < numberOfPoints; ++j) {
                randomNumbersTab[i][j] = (float) Math.random() * number; }}}private void generateData(a) {
        List<Line> lines = new ArrayList<Line>();
        List<AxisValue> axisXValues = new ArrayList<AxisValue>();
        for (int i = 0; i <= numberOfPoints; i++)
            axisXValues.add(i, new AxisValue(i).setLabel(i + "Month"));
        int numberOfLines = 1;
        for (int i = 0; i < numberOfLines; ++i) {
            List<PointValue> values = new ArrayList<PointValue>();
            for (int j = 0; j < numberOfPoints; j++) {
                values.add(new PointValue(j, randomNumbersTab[i][j]));
            }

            Line line = new Line(values);
            line.setColor(ChartUtils.pickColor());    // Set the color to random
            line.setShape(shape);         // Set the shape
            line.setCubic(true);          // set line to curve and vice versa
            line.setFilled(true);          // The Settings are filled
            line.setHasLabels(true);    // Display the sticky note
            line.setHasLabelsOnlyForSelected(true);
            line.setHasLines(true);
            line.setHasPoints(true);
            lines.add(line);
        }

        LineChartData data = new LineChartData(lines);

        data.setAxisXBottom(new Axis(axisXValues).setHasLines(true).setTextColor(Color.BLACK).setName("Date").setHasTiltedLabels(true).setMaxLabelChars(4));
        data.setAxisYLeft(new Axis().setHasLines(true).setName("Income").setTextColor(Color.BLACK).setMaxLabelChars(2)); data.setBaseValue(Float.NEGATIVE_INFINITY); chart.setLineChartData(data); }}Copy the code

1. Get the picture

2. The detail

1. ResetViewport method

Set the Y-axis from 0 to number, which I'm going to set to 60.

2. GenerateValues method

Generate random numbers from 0 to 60, maxNumberOfLines set the number of lines I set to one, numberOfPoints set the numberOfPoints I set to 6

3. The generateData method (Focus on) maximum content

Illustration: == MY consideration may not be very thoughtful, you can try more, maybe I can learn more functions. = =

If I have time, I’ll talk about statistics, pie charts, etc.