Android仿微信、QQ附近好友雷達掃描效果

1.概述

　　最近一直到在帶實習生，因為人比較多，所以很長一段時間沒有更新博客了，今天更新一篇雷達掃描附近好友效果，以後盡量每周更新一篇，先看一下效果：

2．實現　

1、效果分析

效果分為兩個部分，一個是上半部分的自定義RadarView，還有就是下半部分的ViewPager，至於怎麼做到縮放和背景虛化的效果大家可以去看看LazyViewPager這裡不詳細介紹，這裡主要實現掃描效果部分。

2、掃描效果實現

2.1自定義RadarView在onDraw()方法中畫六個圓圈，至於圓圈的半徑是多少我們需要通過onMeasure(int widthMeasureSpec, int heightMeasureSpec)測量方法獲取控件的寬高來確定圓的半徑，每個圓的半徑是寬度的1 / 13f, 2 / 13f, 3 / 13f, 4 / 13f, 5 / 13f, 6 / 13f，這只是自己測試出來感覺比較舒適的效果，下面請看代碼：

//每個圓圈所占的比例
private static float[] circleProportion = {1 / 13f, 2 / 13f, 3 / 13f, 4 / 13f, 5 / 13f, 6 / 13f};
private Paint mPaintCircle;//畫圓需要用到的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) {
 // 獲取控件的寬高
 setMeasuredDimension(measureSize(widthMeasureSpec), measureSize(widthMeasureSpec));
 mWidth = getMeasuredWidth();
 mHeight = getMeasuredHeight();
 mWidth = mHeight = Math.min(mWidth, mHeight);
 }

 @Override
 protected void onDraw(Canvas canvas) {
 // 繪制六個白色圓圈
 drawCircle(canvas);
 }

 /**
 * 繪制圓線圈
 *
 * @param canvas
 */
 private void drawCircle(Canvas canvas) {
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[1], mPaintLine); // 繪制最小圓
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[1], mPaintLine); // 繪制小圓
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[2], mPaintLine); // 繪制中圓
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[3], mPaintLine); // 繪制中大圓
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[4], mPaintLine); // 繪制大圓
 canvas.drawCircle(mWidth / 2, mHeight / 2, mWidth * circleProportion[5], mPaintLine); // 繪制大大圓
 }
}

2.2下面需要去畫中間的用戶圖像，可以運行看看中間的六個圓圈有沒有達到效果，這裡就不看了直接在onDraw()方法中畫中間圖像：

 private Bitmap centerBitmap;//最中間icon

 private void init(){
 // 通過bitmap工廠區獲取用戶圖像的bitmap
 centerBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.circle_photo);
 }

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

 /**
 * 繪制最中間的圖標
 *
 * @param canvas
 */
 private void drawCenterIcon(Canvas canvas) {
 int iconWidth = mWidth * circleProportion[0];
 canvas.drawBitmap(centerBitmap, 0,0,iconWidth ,iconWidth , null);
 }

2.3最後只需要實現這個掃描的效果這個控件基本就完成了，第一需要開啟線程不斷調用invalidate()去更新onDraw()方法，第二需要熟悉掃描渲染SweepGradient這個類，如果這兩個都沒問題那麼大功告成：

private Paint mPaintScan;//畫掃描需要用到的paint
private Matrix matrix = new Matrix();//旋轉需要的矩陣
private int mRoteDegree;//掃描旋轉的角度
private Shader scanShader;//掃描渲染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) {
 //設置掃描渲染的shader
 scanShader = new SweepGradient(mWidth / 2, mHeight / 2,
  new int[]{Color.TRANSPARENT, Color.parseColor("#84B5CA")}, null);
 }

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

 /**
 * 繪制掃描
 *
 * @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.到這裡我們來看一下掃描RadarView的效果

3. 實現添加數據效果RadarViewGroup,我們的圖像附近點需要加入ViewGroup這裡又需要自定義了，這裡簡單說一下自定ViewGroup：
1）.onMeasure()測量方法這裡就不說了
2）.只要搞清楚onLayout()方法是干嘛的就Ok,ViewGroup裡面的子View都顯示在什麼位置就是寫在這個方法裡面的，換句話說有的隔得近有的隔得遠都是由 child.layout(int l, int t, int r, int b)決定的，下面我們看一下代碼：

 public class RadarViewGroup extends ViewGroup implements RadarView.IScanningListener {
 private int mWidth, mHeight;//viewgroup的寬高
 private SparseArray<Float> scanAngleList = new SparseArray<>();//記錄展示的item所在的掃描位置角度
 private SparseArray<Info> mDatas;//數據源
 private int dataLength;//數據源長度
 private int minItemPosition;//最小距離的item所在數據源中的位置
 private CircleView currentShowChild;//當前展示的item
 private CircleView minShowChild;//最小距離的item
 private IRadarClickListener iRadarClickListener;//雷達圖中點擊監聽CircleView小圓點回調接口

 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);
 //測量每個children
 measureChildren(widthMeasureSpec, heightMeasureSpec);
 for (int i = 0; i < getChildCount(); i++) {
  View child = getChildAt(i);
  if (child.getId() == R.id.id_scan_circle) {
  //為雷達掃描圖設置需要的屬性
  ((RadarView) child).setScanningListener(this);
  //考慮到數據沒有添加前掃描圖在掃描，但是不會開始為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();
 //首先放置雷達掃描圖
 View view = findViewById(R.id.id_scan_circle);
 if (view != null) {
  view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
 }
 //放置雷達圖中需要展示的item圓點
 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跳過
  continue;
  }
  //設置CircleView小圓點的坐標信息
  //坐標 = 旋轉角度 * 半徑 * 根據遠近距離的不同計算得到的應該占的半徑比例
  ((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);
  //如果掃描角度記錄SparseArray中的對應的item的值為0，
  // 說明還沒有掃描到該item，跳過對該item的layout
  //（scanAngleList設置數據時全部設置的value=0，
  // 當onScanning時，value設置的值始終不會0，具體可以看onScanning中的實現）
  if (scanAngleList.get(i - 1) == 0) {
  continue;
  }
  //放置Circle小圓點
  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);
  //設置點擊事件
  child.setOnClickListener(new OnClickListener() {
  @Override
  public void onClick(View v) {
   resetAnim(currentShowChild);
   currentShowChild = (CircleView) child;
   //因為雷達圖是childAt(0),所以這裡需要作-1才是正確的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;

 }

 /**
 * 設置數據
 *
 * @param mDatas
 */
 public void setDatas(SparseArray<Info> mDatas) {
 this.mDatas = mDatas;
 dataLength = mDatas.size();
 float min = Float.MAX_VALUE;
 float max = Float.MIN_VALUE;
 //找到距離的最大值，最小值對應的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);
 }
 //根據數據源信息動態添加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));
  }
  //根據遠近距離的不同計算得到的應該占的半徑比例 0.312-0.832
  circleView.setProportion((mDatas.get(i).getDistance() / max + 0.6f) * 0.52f);
  if (minItemPosition == i) {
  minShowChild = circleView;
  }
  addView(circleView);
 }
 }

 /**
 * 雷達圖沒有掃描完畢時回調
 *
 * @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();
 }

 /**
 * 雷達圖掃描完畢時回調
 */
 @Override
 public void onScanSuccess() {
 LogUtil.m("完成回調");
 resetAnim(currentShowChild);
 currentShowChild = minShowChild;
 startAnim(currentShowChild, minItemPosition);
 }

 /**
 * 恢復CircleView小圓點原大小
 *
 * @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小圓點大小
 *
 * @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();
 }
 }

 /**
 * 雷達圖中點擊監聽CircleView小圓點回調接口
 */
 public interface IRadarClickListener {
 void onRadarItemClick(int position);
 }

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

源碼下載：http://xiazai.jb51.net/201611/yuanma/AndroidRadarScan(jb51.net).rar

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