1.概述
这一期的效果，我记得我是仿照别人的方式实现的，具体记不太清了（早几年的事了），附具体效果图：
这里写图片描述
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,也可以去慕课网 (hyman) 看看http://www.imooc.com/view/226，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，接下来直接在 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
这里写图片描述
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 ：
onMeasure() 测量方法这里就不说了，具体请看这里 自定义View简介 - onMeasure,onDraw,自定义属性
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);
}
}
所有分享大纲：Android进阶之旅 - 自定义View篇
