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); } }
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持查字典教程网。
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