Android仿微信、QQ附近好友雷达扫描效果

//每个圆圈所占的比例
private static float[] circleProportion = {1 / 13f, 2 / 13f, 3 / 13f, 4 / 13f, 5 / 13f, 6 / 13f};
private Paint mPaintCircle;//画圆需要用到的paint

public class RadarView extends View {
 public RadarView(Context context) {
 this(context, null);
 }

 public RadarView(Context context, AttributeSet attrs) {
 this(context, attrs, 0);
 }

 public RadarView(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 init();
 }


 private void init() {
 mPaintCircle = new Paint();
 mPaintCircle.setColor(Color.WHITE);
 mPaintCircle.setAntiAlias(true);
 }

 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 // 获取控件的宽高
 setMeasuredDimension(measureSize(widthMeasureSpec), measureSize(widthMeasureSpec));
 mWidth = getMeasuredWidth();
 mHeight = getMeasuredHeight();
 mWidth = mHeight = Math.min(mWidth, mHeight);
 }

 @Override
 protected void onDraw(Canvas canvas) {
 // 绘制六个白色圆圈
 drawCircle(canvas);
 }

 /**
 * 绘制圆线圈
 *
 * @param canvas
 */
 private void drawCircle(Canvas canvas) {
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[1], mPaintLine); // 绘制最小圆
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[1], mPaintLine); // 绘制小圆
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[2], mPaintLine); // 绘制中圆
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[3], mPaintLine); // 绘制中大圆
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[4], mPaintLine); // 绘制大圆
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[5], mPaintLine); // 绘制大大圆
 }
}

 private Bitmap centerBitmap;//最中间icon

 private void init(){
 // 通过bitmap工厂区获取用户图像的bitmap
 centerBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.circle_photo);
 }

 @Override
 protected void onDraw(Canvas canvas) {
 drawCenterIcon(canvas);
 }

 /**
 * 绘制最中间的图标
 *
 * @param canvas
 */
 private void drawCenterIcon(Canvas canvas) {
 int icOnWidth= mWidth * circleProportion[0];
 canvas.drawBitmap(centerBitmap, 0,0,iconWidth ,iconWidth , null);
 }

private Paint mPaintScan;//画扫描需要用到的paint
private Matrix matrix = new Matrix();//旋转需要的矩阵
private int mRoteDegree;//扫描旋转的角度
private Shader scanShader;//扫描渲染shader

public Runnable run = new Runnable() {
 @Override
 public void run() {
  mRoteDegree +=2;
  mRoteMatrix.postRotate(mRoteDegree,cx,cy);
  invalidate();
  postDelayed(run,60);
 }
 };

@Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 //设置扫描渲染的shader
 scanShader = new SweepGradient(mWidth / 2, mHeight / 2,
  new int[]{Color.TRANSPARENT, Color.parseColor("#84B5CA")}, null);
 }

 @Override
 protected void onDraw(Canvas canvas) {
 drawScan(canvas);
 }

 /**
 * 绘制扫描
 *
 * @param canvas
 */
 private void drawScan(Canvas canvas) {
 canvas.save();
 mPaintScan.setShader(scanShader);
 canvas.concat(matrix);
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[4], mPaintScan);
 canvas.restore();
 }

 public class RadarViewGroup extends ViewGroup implements RadarView.IScanningListener {
 private int mWidth, mHeight;//viewgroup的宽高
 private SparseArray scanAngleList = new SparseArray<>();//记录展示的item所在的扫描位置角度
 private SparseArray mDatas;//数据源
 private int dataLength;//数据源长度
 private int minItemPosition;//最小距离的item所在数据源中的位置
 private CircleView currentShowChild;//当前展示的item
 private CircleView minShowChild;//最小距离的item
 private IRadarClickListener iRadarClickListener;//雷达图中点击监听CircleView小圆点回调接口

 public void setiRadarClickListener(IRadarClickListener iRadarClickListener) {
 this.iRadarClickListener = iRadarClickListener;
 }

 public RadarViewGroup(Context context) {
 this(context, null);
 }

 public RadarViewGroup(Context context, AttributeSet attrs) {
 this(context, attrs, 0);
 }

 public RadarViewGroup(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 }


 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 setMeasuredDimension(measureSize(widthMeasureSpec), measureSize(heightMeasureSpec));
 mWidth = getMeasuredWidth();
 mHeight = getMeasuredHeight();
 mWidth = mHeight = Math.min(mWidth, mHeight);
 //测量每个children
 measureChildren(widthMeasureSpec, heightMeasureSpec);
 for (int i = 0; i  0) {
   ((RadarView) child).setMaxScanItemCount(mDatas.size());
   ((RadarView) child).startScan();
  }
  continue;
  }
 }
 }

 @Override
 protected void onLayout(boolean changed, int l, int t, int r, int b) {
 int childCount = getChildCount();
 //首先放置雷达扫描图
 View view = findViewById(R.id.id_scan_circle);
 if (view != null) {
  view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
 }
 //放置雷达图中需要展示的item圆点
 for (int i = 0; i  mDatas) {
 this.mDatas = mDatas;
 dataLength = mDatas.size();
 float min = Float.MAX_VALUE;
 float max = Float.MIN_VALUE;
 //找到距离的最大值，最小值对应的minItemPosition
 for (int j = 0; j  max) {
  max = item.getDistance();
  }
  scanAngleList.put(j, 0f);
 }
 //根据数据源信息动态添加CircleView
 for (int i = 0; i