程序员也是可以很浪……漫…..的在Android中实现了类似的效果。先贴上最终效果图：

生成心形线

心形线的表达式可以参考：桃心线。里面对桃心线的表达式解析的挺好。可以通过使用极坐标的方式，传入角度和距离（常量）计算出对应的坐标点。其中距离是常量值，不需改变，变化的是角度。
桃心线极坐标方程式为：

x=16×sin3α
y=13×cosα?5×cos2α?2×cos3α?cos4α

如果生成的桃心线不够大，可以吧x、y乘以一个常数，使之变大。考虑到大部分人都不愿去研究具体的数学问题，我们直接把前面HTML5的JS代码直接翻译成Java代码就好。

首先定义花瓣类Petal：

import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;

public class Petal {
    private float stretchA;//第一个控制点延长线倍数
    private float stretchB;//第二个控制点延长线倍数
    private float startAngle;//起始旋转角，用于确定第一个端点
    private float angle;//两条线之间夹角，由起始旋转角和夹角可以确定第二个端点
    private int radius = 2;//花芯的半径
    private float growFactor;//增长因子，花瓣是有开放的动画效果，这个参数决定花瓣展开速度
    private int color;//花瓣颜色
    private boolean isFinished = false;//花瓣是否绽放完成
    private Path path = new Path();//用于保存三次贝塞尔曲线
    private Paint paint = new Paint();//画笔
    //构造函数，由花朵类调用
    public Petal(float stretchA, float stretchB, float startAngle, float angle, int color, float growFactor) {
        this.stretchA = stretchA;
        this.stretchB = stretchB;
        this.startAngle = startAngle;
        this.angle = angle;
        this.color = color;
        this.growFactor = growFactor;
        paint.setColor(color);
    }
    //用于渲染花瓣，通过不断更改半径使得花瓣越来越大
    public void render(Point p, int radius, Canvas canvas) {
        if (this.radius <= radius) {
            this.radius += growFactor; // / 10;
        } else {
            isFinished = true;
        }
        this.draw(p, canvas);
    }

    //绘制花瓣，参数p是花芯的圆心的坐标
    private void draw(Point p, Canvas canvas) {
        if (!isFinished) {

            path = new Path();
            //将向量（0，radius）旋转起始角度，第一个控制点根据这个旋转后的向量计算
            Point t = new Point(0, this.radius).rotate(MyUtil.degrad(this.startAngle));
            //第一个端点，为了保证圆心不会随着radius增大而变大这里固定为3
            Point v1 = new Point(0, 3).rotate(MyUtil.degrad(this.startAngle));
            //第二个端点
            Point v2 = t.clone().rotate(MyUtil.degrad(this.angle));
            //延长线，分别确定两个控制点
            Point v3 = t.clone().mult(this.stretchA);
            Point v4 = v2.clone().mult(this.stretchB);
            //由于圆心在p点，因此，每个点要加圆心坐标点
            v1.add(p);
            v2.add(p);
            v3.add(p);
            v4.add(p);
            path.moveTo(v1.x, v1.y);
            //参数分别是：第一个控制点，第二个控制点，终点
            path.cubicTo(v3.x, v3.y, v4.x, v4.y, v2.x, v2.y);
        }
        canvas.drawPath(path, paint);
    }


}

花瓣类是最重要的类，因为真正绘制在屏幕上的是一个个小花瓣。每个花朵包含一系列花瓣，花朵类Bloom如下：

import android.graphics.Canvas;

import java.util.ArrayList;

public class Bloom {
    private int color;//整个花朵的颜色
    private Point point;//花芯圆心
    private int radius; //花芯半径
    private ArrayList<Petal> petals;//用于保存花瓣

    public Point getPoint() {
        return point;
    }


    public Bloom(Point point, int radius, int color, int petalCount) {
        this.point = point;
        this.radius = radius;
        this.color = color;
        petals = new ArrayList<>(petalCount);


        float angle = 360f / petalCount;
        int startAngle = MyUtil.randomInt(0, 90);
        for (int i = 0; i < petalCount; i++) {
            //随机产生第一个控制点的拉伸倍数
            float stretchA = MyUtil.random(Garden.Options.minPetalStretch, Garden.Options.maxPetalStretch);
            //随机产生第二个控制地的拉伸倍数
            float stretchB = MyUtil.random(Garden.Options.minPetalStretch, Garden.Options.maxPetalStretch);
            //计算每个花瓣的起始角度
            int beginAngle = startAngle + (int) (i * angle);
            //随机产生每个花瓣的增长因子（即绽放速度）
            float growFactor = MyUtil.random(Garden.Options.minGrowFactor, Garden.Options.maxGrowFactor);
            //创建一个花瓣，并添加到花瓣列表中
            this.petals.add(new Petal(stretchA, stretchB, beginAngle, angle, color, growFactor));
        }
    }

    //绘制花朵
    public void draw(Canvas canvas) {
        Petal p;
        for (int i = 0; i < this.petals.size(); i++) {
            p = petals.get(i);
            //渲染每朵花朵
            p.render(point, this.radius, canvas);

        }

    }

    public int getColor() {
        return color;
    }
}

接下来是花园类Garden，主要用于创建花朵以及一些相关配置：

public class Garden {
    //创建一个随机的花朵
    public Bloom createRandomBloom(int x, int y) {
        //创建一个随机的花朵半径
        int radius = MyUtil.randomInt(Options.minBloomRadius, Options.maxBloomRadius);
        //创建一个随机的花朵颜色
        int color = MyUtil.randomrgba(Options.minRedColor, Options.maxRedColor, Options.minGreenColor, Options.maxGreenColor, Options.minBlueColor, Options.maxBlueColor, Options.opacity);
        //创建随机的花朵中花瓣个数
        int petalCount = MyUtil.randomInt(Options.minPetalCount, Options.maxPetalCount);
        return createBloom(x, y, radius, color, petalCount);
    }

    //创建花朵
    public Bloom createBloom(int x, int y, int radius, int color, int petalCount) {
        return new Bloom(new Point(x, y), radius, color, petalCount);
    }

    static class Options {
        //用于控制产生随机花瓣个数范围
        public static int minPetalCount = 8;
        public static int maxPetalCount = 15;
        //用于控制产生延长线倍数范围
        public static float minPetalStretch = 2f;
        public static float maxPetalStretch = 3.5f;
        //用于控制产生随机增长因子范围,增长因子决定花瓣绽放速度
        public static float minGrowFactor = 1f;
        public static float maxGrowFactor = 1.1f;
        //用于控制产生花朵半径随机数范围
        public static int minBloomRadius = 8;
        public static int maxBloomRadius = 10;
        //用于产生随机颜色
        public static int minRedColor = 128;
        public static int maxRedColor = 255;
        public static int minGreenColor = 0;
        public static int maxGreenColor = 128;
        public static int minBlueColor = 0;
        public static int maxBlueColor = 128;
        //花瓣的透明度
        public static int opacity = 50;//0.1
    }
}

考虑到刷新的比较频繁，选择使用SurfaceView作为显示视图。自定义一个HeartView继承SurfaceView。代码如下：

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

import java.util.ArrayList;

public class HeartView extends SurfaceView implements SurfaceHolder.Callback {
    SurfaceHolder surfaceHolder;
    int offsetX;
    int offsetY;
    private Garden garden;
    private int width;
    private int height;
    private Paint backgroundPaint;
    private boolean isDrawing = false;
    private Bitmap bm;
    private Canvas canvas;
    private int heartRadio = 1;

    public HeartView(Context context) {
        super(context);
        init();
    }

    public HeartView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }


    private void init() {
        surfaceHolder = getHolder();
        surfaceHolder.addCallback(this);
        garden = new Garden();
        backgroundPaint = new Paint();
        backgroundPaint.setColor(Color.rgb(0xff, 0xff, 0xe0));


    }

    ArrayList<Bloom> blooms = new ArrayList<>();

    public Point getHeartPoint(float angle) {
        float t = (float) (angle / Math.PI);
        float x = (float) (heartRadio * (16 * Math.pow(Math.sin(t), 3)));
        float y = (float) (-heartRadio * (13 * Math.cos(t) - 5 * Math.cos(2 * t) - 2 * Math.cos(3 * t) - Math.cos(4 * t)));

        return new Point(offsetX + (int) x, offsetY + (int) y);
    }


    //绘制列表里所有的花朵
    private void drawHeart() {
        canvas.drawRect(0, 0, width, height, backgroundPaint);
        for (Bloom b : blooms) {
            b.draw(canvas);
        }
        Canvas c = surfaceHolder.lockCanvas();

        c.drawBitmap(bm, 0, 0, null);

        surfaceHolder.unlockCanvasAndPost(c);

    }

    public void reDraw() {
        blooms.clear();


        drawOnNewThread();
    }

    @Override
    public void draw(Canvas canvas) {
        super.draw(canvas);

    }

    //开启一个新线程绘制
    private void drawOnNewThread() {
        new Thread() {
            @Override
            public void run() {
                if (isDrawing) return;
                isDrawing = true;

                float angle = 10;
                while (true) {

                    Bloom bloom = getBloom(angle);
                    if (bloom != null) {
                        blooms.add(bloom);
                    }
                    if (angle >= 30) {
                        break;
                    } else {
                        angle += 0.2;
                    }
                    drawHeart();
                    try {
                        sleep(20);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                isDrawing = false;
            }
        }.start();
    }


    private Bloom getBloom(float angle) {

        Point p = getHeartPoint(angle);

        boolean draw = true;
        /**循环比较新的坐标位置是否可以创建花朵,
         * 为了防止花朵太密集
         * */
        for (int i = 0; i < blooms.size(); i++) {

            Bloom b = blooms.get(i);
            Point bp = b.getPoint();
            float distance = (float) Math.sqrt(Math.pow(p.x - bp.x, 2) + Math.pow(p.y - bp.y, 2));
            if (distance < Garden.Options.maxBloomRadius * 1.5) {
                draw = false;
                break;
            }
        }
        //如果位置间距满足要求，就在该位置创建花朵并将花朵放入列表
        if (draw) {
            Bloom bloom = garden.createRandomBloom(p.x, p.y);
            return bloom;
        }
        return null;
    }


    @Override
    public void surfaceCreated(SurfaceHolder holder) {


    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

        this.width = width;
        this.height = height;
        //我的手机宽度像素是1080，发现参数设置为30比较合适，这里根据不同的宽度动态调整参数
        heartRadio = width * 30 / 1080;

        offsetX = width / 2;
        offsetY = height / 2 - 55;
        bm = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
        canvas = new Canvas(bm);
        drawOnNewThread();
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {

    }
}

还有两个比较重要的工具类
Point.java保存点信息，或者说是向量信息。包含向量的基本运算。

public class Point {
    public int x;
    public int y;

    public Point(int x, int y) {
        this.x = x;
        this.y = y;
    }

    //旋转
    public Point rotate(float theta) {
        int x = this.x;
        int y = this.y;
        this.x = (int) (Math.cos(theta) * x - Math.sin(theta) * y);
        this.y = (int) (Math.sin(theta) * x + Math.cos(theta) * y);
        return this;
    }

    //乘以一个常数
    public Point mult(float f) {
        this.x *= f;
        this.y *= f;
        return this;
    }

    //复制
    public Point clone() {
        return new Point(this.x, this.y);
    }

    //该点与圆心距离
    public float length() {
        return (float) Math.sqrt(this.x * this.x + this.y * this.y);
    }

    //向量相减
    public Point subtract(Point p) {
        this.x -= p.x;
        this.y -= p.y;
        return this;
    }

    //向量相加
    public Point add(Point p) {
        this.x += p.x;
        this.y += p.y;
        return this;
    }

    public Point set(int x, int y) {
        this.x = x;
        this.y = y;
        return this;
    }
}

工具类MyUtil.java主要是产生随机数、颜色等

import android.graphics.Color;

public class MyUtil {
    public static float circle = (float) (2 * Math.PI);

    public static int rgba(int r, int g, int b, int a) {
        return Color.argb(a, r, g, b);
    }

    public static int randomInt(int min, int max) {
        return (int) Math.floor(Math.random() * (max - min + 1)) + min;
    }

    public static float random(float min, float max) {
        return (float) (Math.random() * (max - min) + min);
    }

    //产生随机的argb颜色
    public static int randomrgba(int rmin, int rmax, int gmin, int gmax, int bmin, int bmax, int a) {
        int r = Math.round(random(rmin, rmax));
        int g = Math.round(random(gmin, gmax));
        int b = Math.round(random(bmin, bmax));
        int limit = 5;
        if (Math.abs(r - g) <= limit && Math.abs(g - b) <= limit && Math.abs(b - r) <= limit) {
            return rgba(rmin, rmax, gmin, gmax);
        } else {
            return rgba(r, g, b, a);
        }
    }

    //角度转弧度
    public static float degrad(float angle) {
        return circle / 360 * angle;
    }
}

下面这个呢是设置一个沉浸式

@Override
public void onWindowFocusChanged(boolean hasFocus) {
    super.onWindowFocusChanged(hasFocus);
    if (hasFocus && Build.VERSION.SDK_INT >= 19) {
        View decorView = getWindow().getDecorView();
        decorView.setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
    }
}

设置好的自定义呢别忘记进行使用哦。。。。。。。。。。。。。。。