在Android中利用动画效果绘制正弦波

我们都知道正弦曲线的表达式为y=Asin(ωx+φ)+k，所以，在该demo中，我自定义一个view，在view的onDraw函数里手动绘制波浪效果的正弦函数，根据x坐标和正弦曲线表达式获取y坐标，此时y=10 * Math.sin((i + angle) * Math.PI / 180) + 20;
主要代码：

@Override
        public void onDraw(Canvas canvas) {
                // TODO Auto-generated method stub
                super.onDraw(canvas);
                setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
                int height = getHeight();
                int width = getWidth();
                paint1.setColor(Color.rgb(205, 243, 246));
                paint2.setAlpha(200);
                paint2.setColor(Color.rgb(150, 206, 231));
                paint3.setAlpha(150);
                paint3.setColor(Color.rgb(89, 186, 231));
                double lineX = 0;
                double lineY1 = 0;
                double lineY2 = 0;
                double lineY3 = 0;
                for (int i = 0; i < width; i++) {
                        lineX = i;
                        if (isRun) {
                                lineY1 = Math.sin((i + angle) * Math.PI / 180);
                                lineY2 = 10 * Math.sin((i + angle) * Math.PI / 180) + 20;
                                lineY3 = 20 * Math.sin((i + angle) * Math.PI / 180) + 50;
                        } else {
                                lineY1 = 0;
                                lineY2 = 20;
                                lineY3 = 50;
                        }
                        canvas.drawLine((int) lineX, (int) (lineY1 + height / 1.5),
                                        (int) lineX + 1, (int) (lineY2 + height / 1.5), paint1);
                        canvas.drawLine((int) lineX, (int) (lineY2 + height / 1.5),
                                        (int) lineX + 1, (int) (lineY3 + height / 1.5), paint2);
                        canvas.drawLine((int) lineX, (int) (lineY3 + height / 1.5),
                                        (int) lineX + 1, height, paint3);
                }

        }

开启线程进行每隔1毫毛angle+1，当angle为360的时候，设置angle为0：

@Override
        public void run() {
                // TODO Auto-generated method stub
                while (isRun) {
                        angle++;
                        if (angle == 360) {
                                angle = 0;
                        }
                        try {
                                Thread.sleep(1);
                        } catch (InterruptedException e) {
                                // TODO Auto-generated catch block
                                e.printStackTrace();
                        }
                }
        }

        public void start() {
                isRun = true;
                new Thread(this).start();
        }

        public void stop() {
                isRun = false;
                angle = 0;
        }