在Android中有没有办法绘制图形和图表？

Question

我是Java的新手，也是Android的新手。我正在尝试编写一个Android应用程序，该应用程序基于日期对用户的数据进行图形处理。有没有一种方法可以在Java中不使用JavaScript（我不知道）？

Answer 1

尝试下面的代码

GraphActivity类

  package com.graph;
 import android.app.Activity;
 import android.os.Bundle;

 public class GraphActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    float[] values = new float[] { 2.0f,1.5f, 2.5f, 1.0f , 3.0f };
    String[] verlabels = new String[] { "great", "ok", "bad" };
    String[] horlabels = new String[] { "today", "tomorrow", "next week", "next month" };
    GraphView graphView = new GraphView(this, values, "GraphViewDemo",horlabels, verlabels, GraphView.LINE);
    setContentView(graphView);
}
}

GraphView类

package com.graph;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Align;
import android.view.View;


public class GraphView extends View {

public static boolean BAR = true;
public static boolean LINE = false;

private Paint paint;
private float[] values;
private String[] horlabels;
private String[] verlabels;
private String title;
private boolean type;

public GraphView(Context context, float[] values, String title, String[] horlabels, String[] verlabels, boolean type) {
    super(context);
    if (values == null)
        values = new float[0];
    else
        this.values = values;
    if (title == null)
        title = "";
    else
        this.title = title;
    if (horlabels == null)
        this.horlabels = new String[0];
    else
        this.horlabels = horlabels;
    if (verlabels == null)
        this.verlabels = new String[0];
    else
        this.verlabels = verlabels;
    this.type = type;
    paint = new Paint();
}

@Override
protected void onDraw(Canvas canvas) {
    float border = 20;
    float horstart = border * 2;
    float height = getHeight();
    float width = getWidth() - 1;
    float max = getMax();
    float min = getMin();
    float diff = max - min;
    float graphheight = height - (2 * border);
    float graphwidth = width - (2 * border);

    paint.setTextAlign(Align.LEFT);
    int vers = verlabels.length - 1;
    for (int i = 0; i < verlabels.length; i++) {
        paint.setColor(Color.DKGRAY);
        float y = ((graphheight / vers) * i) + border;
        canvas.drawLine(horstart, y, width, y, paint);
        paint.setColor(Color.WHITE);
        canvas.drawText(verlabels[i], 0, y, paint);
    }
    int hors = horlabels.length - 1;
    for (int i = 0; i < horlabels.length; i++) {
        paint.setColor(Color.DKGRAY);
        float x = ((graphwidth / hors) * i) + horstart;
        canvas.drawLine(x, height - border, x, border, paint);
        paint.setTextAlign(Align.CENTER);
        if (i==horlabels.length-1)
            paint.setTextAlign(Align.RIGHT);
        if (i==0)
            paint.setTextAlign(Align.LEFT);
        paint.setColor(Color.WHITE);
        canvas.drawText(horlabels[i], x, height - 4, paint);
    }

    paint.setTextAlign(Align.CENTER);
    canvas.drawText(title, (graphwidth / 2) + horstart, border - 4, paint);

    if (max != min) {
        paint.setColor(Color.LTGRAY);
        if (type == BAR) {
            float datalength = values.length;
            float colwidth = (width - (2 * border)) / datalength;
            for (int i = 0; i < values.length; i++) {
                float val = values[i] - min;
                float rat = val / diff;
                float h = graphheight * rat;
                canvas.drawRect((i * colwidth) + horstart, (border - h) + graphheight, ((i * colwidth) + horstart) + (colwidth - 1), height - (border - 1), paint);
            }
        } else {
            float datalength = values.length;
            float colwidth = (width - (2 * border)) / datalength;
            float halfcol = colwidth / 2;
            float lasth = 0;
            for (int i = 0; i < values.length; i++) {
                float val = values[i] - min;
                float rat = val / diff;
                float h = graphheight * rat;
                if (i > 0)
                    canvas.drawLine(((i - 1) * colwidth) + (horstart + 1) + halfcol, (border - lasth) + graphheight, (i * colwidth) + (horstart + 1) + halfcol, (border - h) + graphheight, paint);
                lasth = h;
            }
        }
    }
}

private float getMax() {
    float largest = Integer.MIN_VALUE;
    for (int i = 0; i < values.length; i++)
        if (values[i] > largest)
            largest = values[i];
    return largest;
}

private float getMin() {
    float smallest = Integer.MAX_VALUE;
    for (int i = 0; i < values.length; i++)
        if (values[i] < smallest)
            smallest = values[i];
    return smallest;
}

 }

Answer 2

AAChartCore这样的第三方图表框架是一个很好的解决方案。 Android有一个优雅而友好的数据可视化图表框架。功能强大，支持线，样条曲线，面积，面积线，柱状图，条形图，条形图，饼图，散点图，角度规，arearange，areaslinelinerange，columnrange，气泡图，箱形图，误差线，漏斗，瀑布图和极坐标图类型。

这是项目在GitHub上的链接[https://github.com/AAChartModel/AAChartCore] >>

一些漂亮的图表示例如下：

enter image description here