Android仿微信、QQ附近好友雷达扫描效果

1.概述

　　最近一直到在带实习生，因为人比较多，所以很长一段时间没有更新博客了，今天更新一篇雷达扫描附近好友效果，以后尽量每周更新一篇，先看一下效果：

2．实现　

1、效果分析

效果分为两个部分，一个是上半部分的自定义RadarView，还有就是下半部分的ViewPager，至于怎么做到缩放和背景虚化的效果大家可以去看看LazyViewPager这里不详细介绍，这里主要实现扫描效果部分。

2、扫描效果实现

2.1自定义RadarView在onDraw()方法中画六个圆圈，至于圆圈的半径是多少我们需要通过onMeasure(int widthMeasureSpec, int heightMeasureSpec)测量方法获取控件的宽高来确定圆的半径，每个圆的半径是宽度的1 / 13f, 2 / 13f, 3 / 13f, 4 / 13f, 5 / 13f, 6 / 13f，这只是自己测试出来感觉比较舒适的效果，下面请看代码：

//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
 }
}

2.2下面需要去画中间的用户图像，可以运行看看中间的六个圆圈有没有达到效果，这里就不看了直接在onDraw()方法中画中间图像：

 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);
 }

2.3最后只需要实现这个扫描的效果这个控件基本就完成了，第一需要开启线程不断调用invalidate()去更新onDraw()方法，第二需要熟悉扫描渲染SweepGradient这个类，如果这两个都没问题那么大功告成：

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();
 }

2.4.到这里我们来看一下扫描RadarView的效果

3. 实现添加数据效果RadarViewGroup,我们的图像附近点需要加入ViewGroup这里又需要自定义了，这里简单说一下自定ViewGroup：
1）.onMeasure()测量方法这里就不说了
2）.只要搞清楚onLayout()方法是干嘛的就Ok,ViewGroup里面的子View都显示在什么位置就是写在这个方法里面的，换句话说有的隔得近有的隔得远都是由 child.layout(int l, int t, int r, int b)决定的，下面我们看一下代码：

 public class RadarViewGroup extends ViewGroup implements RadarView.IScanningListener {
 private int mWidth, mHeight;//viewgroup的宽高
 private SparseArray<Float> scanAngleList = new SparseArray<>();//记录展示的item所在的扫描位置角度
 private SparseArray<Info> 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 < getChildCount(); i++) {
  View child = getChildAt(i);
  if (child.getId() == R.id.id_scan_circle) {
  //为雷达扫描图设置需要的属性
  ((RadarView) child).setScanningListener(this);
  //考虑到数据没有添加前扫描图在扫描，但是不会开始为CircleView布局
  if (mDatas != null && mDatas.size() > 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 < childCount; i++) {
  final int j = i;
  final View child = getChildAt(i);
  if (child.getId() == R.id.id_scan_circle) {
  //如果不是Circleview跳过
  continue;
  }
  //设置CircleView小圆点的坐标信息
  //坐标 = 旋转角度 * 半径 * 根据远近距离的不同计算得到的应该占的半径比例
  ((CircleView) child).setDisX((float) Math.cos(Math.toRadians(scanAngleList.get(i - 1) - 5))
   * ((CircleView) child).getProportion() * mWidth / 2);
  ((CircleView) child).setDisY((float) Math.sin(Math.toRadians(scanAngleList.get(i - 1) - 5))
   * ((CircleView) child).getProportion() * mWidth / 2);
  //如果扫描角度记录SparseArray中的对应的item的值为0，
  // 说明还没有扫描到该item，跳过对该item的layout
  //（scanAngleList设置数据时全部设置的value=0，
  // 当onScanning时，value设置的值始终不会0，具体可以看onScanning中的实现）
  if (scanAngleList.get(i - 1) == 0) {
  continue;
  }
  //放置Circle小圆点
  child.layout((int) ((CircleView) child).getDisX() + mWidth / 2, (int) ((CircleView) child).getDisY() + mHeight / 2,
   (int) ((CircleView) child).getDisX() + child.getMeasuredWidth() + mWidth / 2,
   (int) ((CircleView) child).getDisY() + child.getMeasuredHeight() + mHeight / 2);
  //设置点击事件
  child.setOnClickListener(new OnClickListener() {
  @Override
  public void onClick(View v) {
   resetAnim(currentShowChild);
   currentShowChild = (CircleView) child;
   //因为雷达图是childAt(0),所以这里需要作-1才是正确的Circle
   startAnim(currentShowChild, j - 1);
   if (iRadarClickListener != null) {
   iRadarClickListener.onRadarItemClick(j - 1);

   }
  }
  });
 }

 }

 private int measureSize(int measureSpec) {
 int result = 0;
 int specMode = MeasureSpec.getMode(measureSpec);
 int specSize = MeasureSpec.getSize(measureSpec);
 if (specMode == MeasureSpec.EXACTLY) {
  result = specSize;
 } else {
  result = 300;
  if (specMode == MeasureSpec.AT_MOST) {
  result = Math.min(result, specSize);
  }
 }
 return result;

 }

 /**
 * 设置数据
 *
 * @param mDatas
 */
 public void setDatas(SparseArray<Info> 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 < dataLength; j++) {
  Info item = mDatas.get(j);
  if (item.getDistance() < min) {
  min = item.getDistance();
  minItemPosition = j;
  }
  if (item.getDistance() > 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 < dataLength; i++) {
  CircleView circleView = new CircleView(getContext());
  if (mDatas.get(i).getSex()) {
  circleView.setPaintColor(getResources().getColor(R.color.bg_color_pink));
  } else {
  circleView.setPaintColor(getResources().getColor(R.color.bg_color_blue));
  }
  //根据远近距离的不同计算得到的应该占的半径比例 0.312-0.832
  circleView.setProportion((mDatas.get(i).getDistance() / max + 0.6f) * 0.52f);
  if (minItemPosition == i) {
  minShowChild = circleView;
  }
  addView(circleView);
 }
 }

 /**
 * 雷达图没有扫描完毕时回调
 *
 * @param position
 * @param scanAngle
 */
 @Override
 public void onScanning(int position, float scanAngle) {
 if (scanAngle == 0) {
  scanAngleList.put(position, 1f);
 } else {
  scanAngleList.put(position, scanAngle);
 }
 requestLayout();
 }

 /**
 * 雷达图扫描完毕时回调
 */
 @Override
 public void onScanSuccess() {
 LogUtil.m("完成回调");
 resetAnim(currentShowChild);
 currentShowChild = minShowChild;
 startAnim(currentShowChild, minItemPosition);
 }

 /**
 * 恢复CircleView小圆点原大小
 *
 * @param object
 */
 private void resetAnim(CircleView object) {
 if (object != null) {
  object.clearPortaitIcon();
  ObjectAnimator.ofFloat(object, "scaleX", 1f).setDuration(300).start();
  ObjectAnimator.ofFloat(object, "scaleY", 1f).setDuration(300).start();
 }

 }

 /**
 * 放大CircleView小圆点大小
 *
 * @param object
 * @param position
 */
 private void startAnim(CircleView object, int position) {
 if (object != null) {
  object.setPortraitIcon(mDatas.get(position).getPortraitId());
  ObjectAnimator.ofFloat(object, "scaleX", 2f).setDuration(300).start();
  ObjectAnimator.ofFloat(object, "scaleY", 2f).setDuration(300).start();
 }
 }

 /**
 * 雷达图中点击监听CircleView小圆点回调接口
 */
 public interface IRadarClickListener {
 void onRadarItemClick(int position);
 }

 /**
 * 根据position，放大指定的CircleView小圆点
 *
 * @param position
 */
 public void setCurrentShowItem(int position) {
 CircleView child = (CircleView) getChildAt(position + 1);
 resetAnim(currentShowChild);
 currentShowChild = child;
 startAnim(currentShowChild, position);
 }
}

源码下载：http://xiazai.jb51.net/201611/yuanma/AndroidRadarScan(jb51.net).rar

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