/** Created by xuzhilei on 2016/8/16. 模仿音乐暂停开始按钮的View */public class PlayButtonView extends View { /** 中心点X轴坐标 */ private int viewCenterX; /** 中心点Y轴坐标 */ private int viewCenterY; /** 有效长度的一般（View长宽较小者的一半） */ private int viewHalfLength; /** 三角形右侧顶点 */ private Point pointA = new Point(); /** 三角形左上顶点 */ private Point pointB = new Point(); /** 三角形左下顶点 */ private Point pointC = new Point(); /** 矩形左边界 */ private int RectLeft; /** 矩形上边界 */ private int RectTOP; /** 矩形右边界 */ private int RectRight; /** 矩形下边界 */ private int RectBottom; /** 三角形的三条边路径 */ private Path path = new Path(); /** 包围最外侧圆环的矩形 */ private RectF rectF = new RectF(); /** 包围进度圆弧的矩形 */ private RectF rectF2 = new RectF(); /** 进度 */ private int progress; /** 暂停中还是播放中 */ private boolean isPlaying = false; /** 是否进行过了测量 */ private boolean isMeasured = false; /** 画笔颜色 */ private int color = 0xffff0099; /** 最外侧圆环画笔 */ private Paint paintA = new Paint(); /** 进度圆弧画笔 */ private Paint paintB = new Paint(); /** 暂停开始画笔 */ private Paint paintC = new Paint(); /** 状态监听器 */ private OnStatusChangeListener onStatusChangeListener; /** 构造器 */ public PlayButtonView(Context context, AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (!isMeasured) { getWidthAndHeight(); isMeasured = true; } } /** 得到视图等的高度宽度尺寸数据 */ private void getWidthAndHeight() { int viewHeight = getMeasuredHeight(); int viewWidth = getMeasuredWidth(); viewCenterX = viewWidth / 2; viewCenterY = viewHeight / 2; viewHalfLength = viewHeight < viewWidth ? viewHeight / 2 : viewWidth / 2; int paintAwidth = viewHalfLength / 15; int paintBwidth = viewHalfLength / 8; rectF.left = viewCenterX - (viewHalfLength - paintAwidth / 2); rectF.top = viewCenterY - (viewHalfLength - paintAwidth / 2); rectF.right = viewCenterX + (viewHalfLength - paintAwidth / 2); rectF.bottom = viewCenterY + (viewHalfLength - paintAwidth / 2); rectF2.left = viewCenterX - (viewHalfLength - paintBwidth / 2); rectF2.top = viewCenterY - (viewHalfLength - paintBwidth / 2); rectF2.right = viewCenterX + (viewHalfLength - paintBwidth / 2); rectF2.bottom = viewCenterY + (viewHalfLength - paintBwidth / 2); paintA.setColor(color); paintA.setStrokeWidth(paintAwidth); paintA.setAntiAlias(true); paintA.setStyle(Paint.Style.STROKE); paintB.setColor(color); paintB.setStrokeWidth(paintBwidth); paintB.setAntiAlias(true); paintB.setStyle(Paint.Style.STROKE); paintC.setColor(color); paintC.setStrokeWidth(1); paintC.setAntiAlias(true); paintC.setStyle(Paint.Style.FILL); pointA.x = viewCenterX + viewHalfLength / 2; pointA.y = viewCenterY; double sin = Math.sin(Math.toRadians(60)); // √(3) / 2 double cos = Math.cos(Math.toRadians(60)); // 1/ 2 pointB.x = (float) ((viewCenterX - cos * viewHalfLength + viewCenterX) / 2); pointB.y = (float) ((viewCenterY - sin * viewHalfLength + viewCenterY) / 2); pointC.x = (float) ((viewCenterX - cos * viewHalfLength + viewCenterX) / 2); pointC.y = (float) ((viewCenterY + sin * viewHalfLength + viewCenterY) / 2); RectLeft = viewCenterX - viewHalfLength / 3; RectTOP = viewCenterY - viewHalfLength / 3; RectRight = viewCenterX + viewHalfLength / 3; RectBottom = viewCenterY + viewHalfLength / 3; } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); // 画未完成进度的圆环 canvas.drawArc(rectF, 0, 360, false, paintA); // 画已经完成进度的圆弧 从-90度开始，即从圆环顶部开始 canvas.drawArc(rectF2, -90, progress * 3.6f, false, paintB); if (isPlaying) { canvas.drawRect(RectLeft, RectTOP, RectRight, RectBottom, paintC); } else { path.reset(); path.moveTo(pointA.x, pointA.y); path.lineTo(pointB.x, pointB.y); path.lineTo(pointC.x, pointC.y); path.close(); canvas.drawPath(path, paintC); } } /** 监听触摸DOWN时间，开始播放，暂停播放 */ @Override public boolean onTouchEvent(MotionEvent event) { if (event.getAction() == MotionEvent.ACTION_DOWN) { isPlaying = !isPlaying; invalidate(); if (isPlaying) { onStatusChangeListener.play(); } else { onStatusChangeListener.pause(); } } return super.onTouchEvent(event); } /** 设置进度 0-100区间 */ public void setProgress(int progress) { if (progress < 0) { progress = 0; } if (progress > 100) { progress = 100; } this.progress = progress; invalidate(); } /** 外界设置播放状态 */ public void setPlaying(boolean isPlaying) { this.isPlaying = isPlaying; invalidate(); } /** 播放暂停状态监听的接口 */ public interface OnStatusChangeListener { void play(); void pause(); } /** 设置监听接口 */ public void setOnStatusChangeListener(OnStatusChangeListener onStatusChangeListener) { this.onStatusChangeListener = onStatusChangeListener; } /** 位置信息 */ private class Point { float x; float y; } 
