本文实例讲述了Android编程使用自定义View实现水波进度效果。分享给大家供大家参考，具体如下：

首先上效果图：

简介：

1.自动适应屏幕大小；
2.水波自动横向滚动；
3.各种绘制参数可通过修改常量进行控制。

代码不多，注释也比较详细，全部贴上：

（一）自定义组件：

/** * 水波进度效果. */public class WaterWaveView extends View { //边框宽度 private int STROKE_WIDTH; //组件的宽，高 private int width, height; /** * 进度条最大值和当前进度值 */ private float max, progress; /** * 绘制波浪的画笔 */ private Paint progressPaint; //波纹振幅与半径之比。(建议设置：<0.1) private static final float A = 0.05f; //绘制文字的画笔 private Paint textPaint; //绘制边框的画笔 private Paint circlePaint; /** * 圆弧圆心位置 */ private int centerX, centerY; //内圆所在的矩形 private RectF circleRectF; public WaterWaveView(Context context) { super(context); init(); } public WaterWaveView(Context context, AttributeSet attrs) { super(context, attrs); init(); } public WaterWaveView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(); } //初始化 private void init() { progressPaint = new Paint(); progressPaint.setColor(Color.parseColor("#77cccc88")); progressPaint.setAntiAlias(true); textPaint = new Paint(); textPaint.setColor(Color.WHITE); textPaint.setAntiAlias(true); circlePaint = new Paint(); circlePaint.setStyle(Paint.Style.STROKE); circlePaint.setAntiAlias(true); circlePaint.setColor(Color.parseColor("#33333333")); autoRefresh(); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (width == 0 || height == 0) { width = getWidth(); height = getHeight(); //计算圆弧半径和圆心点 int circleRadius = Math.min(width, height) >> 1; STROKE_WIDTH = circleRadius / 10; circlePaint.setStrokeWidth(STROKE_WIDTH); centerX = width / 2; centerY = height / 2; VALID_RADIUS = circleRadius - STROKE_WIDTH; RADIANS_PER_X = (float) (Math.PI / VALID_RADIUS); circleRectF = new RectF(centerX - VALID_RADIUS, centerY - VALID_RADIUS, centerX + VALID_RADIUS, centerY + VALID_RADIUS); } } private Rect textBounds = new Rect(); //x方向偏移量 private int xOffset; @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); //绘制圆形边框 canvas.drawCircle(centerX, centerY, VALID_RADIUS + (STROKE_WIDTH >> 1), circlePaint); //绘制水波曲线 canvas.drawPath(getWavePath(xOffset), progressPaint); //绘制文字 textPaint.setTextSize(VALID_RADIUS >> 1); String text1 = String.valueOf(progress); //测量文字长度 float w1 = textPaint.measureText(text1); //测量文字高度 textPaint.getTextBounds("8", 0, 1, textBounds); float h1 = textBounds.height(); float extraW = textPaint.measureText("8") / 3; canvas.drawText(text1, centerX - w1 / 2 - extraW, centerY + h1 / 2, textPaint); textPaint.setTextSize(VALID_RADIUS / 6); textPaint.getTextBounds("M", 0, 1, textBounds); float h2 = textBounds.height(); canvas.drawText("M", centerX + w1 / 2 - extraW + 5, centerY - (h1 / 2 - h2), textPaint); String text3 = "共" + String.valueOf(max) + "M"; float w3 = textPaint.measureText(text3, 0, text3.length()); textPaint.getTextBounds("M", 0, 1, textBounds); float h3 = textBounds.height(); canvas.drawText(text3, centerX - w3 / 2, centerY + (VALID_RADIUS >> 1) + h3 / 2, textPaint); String text4 = "流量剩余"; float w4 = textPaint.measureText(text4, 0, text4.length()); textPaint.getTextBounds(text4, 0, text4.length(), textBounds); float h4 = textBounds.height(); canvas.drawText(text4, centerX - w4 / 2, centerY - (VALID_RADIUS >> 1) + h4 / 2, textPaint); } //绘制水波的路径 private Path wavePath; //每一个像素对应的弧度数 private float RADIANS_PER_X; //去除边框后的半径（即内圆半径） private int VALID_RADIUS; /** * 获取水波曲线（包含圆弧部分）的Path. * * @param xOffset x方向像素偏移量. */ private Path getWavePath(int xOffset) { if (wavePath == null) { wavePath = new Path(); } else { wavePath.reset(); } float[] startPoint = new float[2]; //波浪线起点 float[] endPoint = new float[2]; //波浪线终点 for (int i = 0; i <= VALID_RADIUS * 2; i += 2) { float x = centerX - VALID_RADIUS + i; float y = (float) (centerY + VALID_RADIUS * (1.0f + A) * 2 * (0.5f - progress / max) + VALID_RADIUS * A * Math.sin((xOffset + i) * RADIANS_PER_X)); //只计算内圆内部的点，边框上的忽略 if (calDistance(x, y, centerX, centerY) > VALID_RADIUS) { if (x < centerX) { continue; //左边框,继续循环 } else { break; //右边框,结束循环 } } //第1个点 if (wavePath.isEmpty()) { startPoint[0] = x; startPoint[1] = y; wavePath.moveTo(x, y); } else { wavePath.lineTo(x, y); } endPoint[0] = x; endPoint[1] = y; } if (wavePath.isEmpty()) { if (progress / max >= 0.5f) { //满格 wavePath.moveTo(centerX, centerY - VALID_RADIUS); wavePath.addCircle(centerX, centerY, VALID_RADIUS, Path.Direction.CW); } else { //空格 return wavePath; } } else { //添加圆弧部分 float startDegree = calDegreeByPosition(startPoint[0], startPoint[1]); //0~180 float endDegree = calDegreeByPosition(endPoint[0], endPoint[1]); //180~360 wavePath.arcTo(circleRectF, endDegree - 360, startDegree - (endDegree - 360)); } return wavePath; } private float calDistance(float x1, float y1, float x2, float y2) { return (float) Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2)); } //根据当前位置，计算出进度条已经转过的角度。 private float calDegreeByPosition(float currentX, float currentY) { float a1 = (float) (Math.atan(1.0f * (centerX - currentX) / (currentY - centerY)) / Math.PI * 180); if (currentY < centerY) { a1 += 180; } else if (currentY > centerY && currentX > centerX) { a1 += 360; } return a1 + 90; } public void setMax(int max) { this.max = max; invalidate(); } //直接设置进度值（同步） public void setProgressSync(float progress) { this.progress = progress; invalidate(); } /** * 自动刷新页面，创造水波效果。组件销毁后该线城将自动停止。 */ private void autoRefresh() { new Thread(new Runnable() { @Override public void run() { while (!detached) { xOffset += (VALID_RADIUS >> 4); SystemClock.sleep(100); postInvalidate(); } } }).start(); } //标记View是否已经销毁 private boolean detached = false; @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); detached = true; }}

（二）使用方法：

在xml布局中引入上述组件，然后在activity或fragment中设置属性：

WaterWaveView bar = (WaterWaveView) getActivity().findViewById(R.id.water_wave_view); bar.setMax(500); bar.setProgressSync(361.8f);

更多关于Android相关内容感兴趣的读者可查看本站专题：《Android开发动画技巧汇总》、《Android编程之activity操作技巧总结》、《Android视图View技巧总结》、《Android布局layout技巧总结》、《Android开发入门与进阶教程》、《Android资源操作技巧汇总》及《Android控件用法总结》

希望本文所述对大家Android程序设计有所帮助。