Android自定义半圆形圆盘滚动选择器

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import com.wj.R;
import com.wj.utils.DensityUtil;
import com.wj.utils.ScreenUtils;
import java.util.ArrayList;
import java.util.List;

/**
 * @time 2018/6/8
 * @author JunJieW
 * @since 1376881525@qq.com
 * @description 自定义半圆形展示效果转盘选择器控件
 */
public class RingViewHalf extends ViewGroup {
 /**
 * 上一次滑动的坐标
 */
 private float mLastX;
 private float mLastY;
 /**
 * 检测按下到抬起时使用的时间
 */
 private long mDownTime;
 /**
 * 自动滚动线程
 */
 private ScrollResetRunnable mScrollResetRunnable;
 /**
 * 检测按下到抬起时旋转的角度
 */
 private float mTmpAngle;
 /**
 * 每秒最大移动角度
 */
 private int mMax_Speed;
 /**
 * 如果移动角度达到该值，则屏蔽点击
 */
 private int mMin_Speed;
 /**
 * 圆的直径
 */
 private int mRadius;
 /**
 * 判断是否正在自动滚动
 */
 private boolean isMove;
 /**
 * 布局滚动角度
 */
 private int mStartAngle = 0;
 /**
 * 中间条的宽度
 */
 private int mCircleLineStrokeWidth;
 /**
 * 图片内容偏移角度
 */
 private int mImageAngle;
 /**
 * 是否初始化布局
 */
 private boolean isChekc = false;
 /**
 * 布局view
 */
 private List mImageList = new ArrayList<>();
 /**
 * 是否可点击
 */
 private boolean isCanClick = true;

 /**
 * 图片与环之间的padding
 */
 private int mPadding;
 /**
 * 是否是右边居中的图标为选中图标
 */
 private boolean is_right_select_icon = true;
 /**
 * 是否是右边居中的图标为选中图标
 */
 private Rect select_icon_rect = new Rect();


 //是否能转动
 private boolean mCanScrool;

 public RingViewHalf(Context context) {
 this(context, null, 0);
 }

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

 public RingViewHalf(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);
 //获取自定义控件设置的值
 TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.ringview_half, 0, 0);
 mMax_Speed = array.getInteger(R.styleable.ringview_half_max_speed_rh, 300);
 mMin_Speed = array.getInteger(R.styleable.ringview_half_min_speed_rh, 3);
 mImageAngle = array.getInteger(R.styleable.ringview_half_image_angle_rh, 0);
 mPadding = array.getInteger(R.styleable.ringview_half_image_padding_rh, 0);
 mCanScrool = array.getBoolean(R.styleable.ringview_half_can_scroll_rh, true);
 is_right_select_icon = array.getBoolean(R.styleable.ringview_half_is_right_select_icon_rh, true);

 //获取xml定义的资源文件
 TypedArray mList = context.getResources().obtainTypedArray(array.getResourceId(R.styleable.ringview_half_list_rh, 0));
 int len = mList.length();
 if (len > 0) {
 for (int i = 0; i < len; i++)
 mImageList.add(mList.getResourceId(i, 0));
 } else {
 mImageList.add(R.mipmap.icon);
 mImageList.add(R.mipmap.icon);
 mImageList.add(R.mipmap.icon);
 }
 mList.recycle();
 array.recycle();

 int [] location =new int [2];
 getLocationInWindow(location);
 Log.d("locationInWindow",">>>>X=="+location[0]+"y=="+location[1]);
 addImgIcon();
 }

 @Override
 protected void onLayout(boolean changed, int l, int t, int r, int b) {
 if (!isChekc) {
 initView();
 mRadius = getWidth();
 isChekc = true;
 }

 }

 /**
 * 测量
 */
 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 setMeasuredDimension(widthMeasureSpec, heightMeasureSpec);
 super.onMeasure(widthMeasureSpec, heightMeasureSpec);
 int childCount = this.getChildCount();
 for (int i = 0; i < childCount; i++) {
 View child = this.getChildAt(i);
 this.measureChild(child, widthMeasureSpec, heightMeasureSpec);
 child.getMeasuredWidth();
 }

 }

 /**
 * 排版布局
 */
 private void initView() {
 int width = this.getWidth();
 int height = this.getHeight();
 if (width != height) {
 int min = Math.min(width, height);
 width = min;
 height = min;
 }
 //不同屏幕分辨率下做不同的处理
 float instPadding = 70f;
 if (ScreenUtils.getScreenWidth(getContext())<=720){
 instPadding = 55f;
 }

 //图片摆放的圆弧半径
 mCircleLineStrokeWidth = getChildAt(0).getMeasuredHeight() + DensityUtil.dip2px(getContext(),instPadding) + mPadding;
 //计算图片圆的半径
 final int mContent = width / 2 - mCircleLineStrokeWidth / 2;
 for (int i = 0; i < getChildCount(); i++) {
 View child = this.getChildAt(i);
 //计算每个图片摆放的角度
 int mAnGle = 360 / mImageList.size() * (i + 1) + mImageAngle;
 //获取每个图片摆放的左上角的x和y坐标
 float left = (float) (width / 2 + mContent * Math.cos(mAnGle * Math.PI / 180)) - child.getMeasuredWidth() / 2;
 float top = (float) (height / 2 + mContent * Math.sin(mAnGle * Math.PI / 180)) - child.getMeasuredHeight() / 2;
 /**
 * 一四象限
 */
 if (getQuadrantByAngle(mAnGle) == 1 || getQuadrantByAngle(mAnGle) == 4) {
// child.setRotation(mAnGle - 270);
 /**
  * 二三象限
  */
 } else {
// child.setRotation(mAnGle + 90);
 }

 child.layout((int) left, (int) top, (int) left + child.getMeasuredWidth(), (int) top + child.getMeasuredHeight());


 }

 }

 /**
 * 添加子控件
 */
 private void addImgIcon() {
 for (int i = 1; i < mImageList.size() + 1; i++) {
 //新建imageview
 final ImageView mImageView = new ImageView(getContext());
 mImageView.setImageResource(mImageList.get(i - 1));
 LayoutParams layoutParams = null;

 mImageView.setScaleType(ImageView.ScaleType.FIT_XY);
 if (is_right_select_icon){
 //右侧icon为选中状态
 if (i==mImageList.size()){
  mImageView.setAlpha(1f);
  layoutParams = new LayoutParams(DensityUtil.dip2px(getContext(),40f), DensityUtil.dip2px(getContext(),40f));
 }else {
  mImageView.setAlpha(0.5f);
  layoutParams = new LayoutParams(DensityUtil.dip2px(getContext(),40f), DensityUtil.dip2px(getContext(),40f));
 }
 }else {
 // 左侧icon为选中状态
 if (i==5){
  mImageView.setAlpha(1f);
  layoutParams = new LayoutParams(DensityUtil.dip2px(getContext(),40f), DensityUtil.dip2px(getContext(),40f));
 }else {
  mImageView.setAlpha(0.5f);
  layoutParams = new LayoutParams(DensityUtil.dip2px(getContext(),40f), DensityUtil.dip2px(getContext(),40f));
 }
 }

 mImageView.setLayoutParams(layoutParams);
 final int finalI = i;
 //添加点击事件
 mImageView.setOnClickListener(new OnClickListener() {
 @Override
 public void onClick(View view) {
  if (isCanClick) {
//  Toast.makeText(getContext(),finalI + " ---", Toast.LENGTH_SHORT).show();
  if (mOnLogoItemClick != null)
  mOnLogoItemClick.onItemClick(view, finalI - 1);
  }

 }
 });
 //添加view
 addView(mImageView);
 }
 //添加view点击事件
 setOnClickListener(new OnClickListener() {
 @Override
 public void onClick(View view) {
 if (isCanClick) {
 }
 }
 });

 }

 /**
 * 触摸监听
 */
 @Override
 public boolean dispatchTouchEvent(MotionEvent event) {
 if (mCanScrool) {
 float x = event.getX();
 float y = event.getY();


 switch (event.getAction()) {
 case MotionEvent.ACTION_DOWN:

  mLastX = x;
  mLastY = y;
  mDownTime = System.currentTimeMillis();
  mTmpAngle = 0;

  // 如果当前已经在快速滚动
  if (isMove) {
  // 移除快速滚动的回调
  removeCallbacks(mScrollResetRunnable);
  isMove = false;
  return true;
  }

  break;
 case MotionEvent.ACTION_MOVE:
  /**
  * 获得开始的角度
  */
  float start = getAngle(mLastX, mLastY);
  /**
  * 获得当前的角度
  */
  float end = getAngle(x, y);
  Log.e("TAG", "start = " + start + " , end =" + end);
  // 一四象限
  if (getQuadrant(x, y) == 1 || getQuadrant(x, y) == 4) {
  mStartAngle += end - start;
  mTmpAngle += end - start;
  //二三象限
  } else {
  mStartAngle += start - end;
  mTmpAngle += start - end;
  }
  // 重新布局
  getCheck();

  break;
 case MotionEvent.ACTION_UP:
  // 获取每秒移动的角度
  float anglePerSecond = mTmpAngle * 1000
  / (System.currentTimeMillis() - mDownTime);
  // 如果达到最大速度
  if (Math.abs(anglePerSecond) > mMax_Speed && !isMove) {
  // 惯性滚动
  post(mScrollResetRunnable = new ScrollResetRunnable(anglePerSecond));
  return true;
  }

  // 如果当前旋转角度超过minSpeed屏蔽点击
  if (Math.abs(mTmpAngle) > mMin_Speed) {
  return true;
  }

  break;
 }
 }
 return super.dispatchTouchEvent(event);
 }

 /**
 * 获取移动的角度
 */
 private float getAngle(float xTouch, float yTouch) {
 double x = xTouch - (mRadius / 2d);
 double y = yTouch - (mRadius / 2d);
 return (float) (Math.asin(y / Math.hypot(x, y)) * 180 / Math.PI);
 }

 /**
 * 根据当前位置计算象限
 */
 private int getQuadrant(float x, float y) {
 int tmpX = (int) (x - mRadius / 2);
 int tmpY = (int) (y - mRadius / 2);
 if (tmpX >= 0) {
 return tmpY >= 0 ? 4 : 1;
 } else {
 return tmpY >= 0 ? 3 : 2;
 }

 }

 /**
 * 在activity的onCreate方法中获取当前自定义view中在屏幕中的绝对坐标始终为0，
 * 改成在onWindowFocusChanged函数中获取即可，这时view都已经加载完成
 * 但这里特别注意一点要：如果是fragment种使用该自定义view的话，这里的方法就应该注释掉
 * 因为不但获取到的矩形的值是空的，而且当你的fragment执行了跳转的逻辑后，再返回后会发
 * 一种特别恶心的异常，你获取到判断选中位置的矩形的left，top，right，bottom的值会和
 * 初始化的时候不一样，导致你选中时候的状态出现异常情况，本人已经被坑过，希望后面的同学
 * 一定注意吸取教训
 */
 @Override
 public void onWindowFocusChanged(boolean hasWindowFocus) {
 super.onWindowFocusChanged(hasWindowFocus);

 getSelectIconReft();

 }
 //获取选中icon位置的矩形范围
 private void getSelectIconReft() {

 int [] location = new int [2];
 getLocationOnScreen(location);
 //计算出右侧选中时图标的位置
 if (is_right_select_icon){
 //选中的icon动态设置宽高为60，没选中宽高55，这里60/2为选中按钮的宽度或者高度的一半，即中心点
 select_icon_rect.left = location[0]+getWidth()-mCircleLineStrokeWidth/2-DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.top =(location[1]+getHeight()/2)-DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.right = location[0]+getWidth()-mCircleLineStrokeWidth/2+DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.bottom = (location[1]+getHeight()/2)+DensityUtil.dip2px(getContext(),40f)/2;
 }else {
 //计算出左侧选中时图标的位置
 //选中的icon动态设置宽高为60，没选中宽高55，这里60/2为选中按钮的宽度或者高度的一半，即中心点
 select_icon_rect.left = location[0]+mCircleLineStrokeWidth/2-DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.top = (location[1]+getHeight()/2)-DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.right = location[0]+mCircleLineStrokeWidth/2+DensityUtil.dip2px(getContext(),40f)/2;
 select_icon_rect.bottom = (location[1]+getHeight()/2)+DensityUtil.dip2px(getContext(),40f)/2;
 }
 Log.d("onFocusChanged","-----getHeight=="+getChildAt(0).getHeight()+";getWidth=="+getChildAt(0).getWidth());
 }


 /**
 * 通过角度判断象限
 */
 private int getQuadrantByAngle(int angle) {
 if (angle <= 90) {
 return 4;
 } else if (angle <= 180) {
 return 3;
 } else if (angle <= 270) {
 return 2;
 } else {
 return 1;
 }
 }

 /**
 * 惯性滚动
 */
 private class ScrollResetRunnable implements Runnable {

 private float angelPerSecond;

 public ScrollResetRunnable(float velocity) {
 this.angelPerSecond = velocity;
 }

 public void run() {
 //小于20停止
 if ((int) Math.abs(angelPerSecond) < 20) {
 isMove = false;
 return;
 }
 isMove = true;
 // 滚动时候不断修改滚动角度大小
// mStartAngle += (angelPerSecond / 30);
 mStartAngle += (angelPerSecond / 40);
 //逐渐减小这个值
 angelPerSecond /= 1.0666F;
 postDelayed(this, 30);
 // 重新布局
 getCheck();
 }
 }


 /**
 * 点击事件接口
 */
 public interface OnLogoItemClick {
 void onItemClick(View view, int pos);
 }

 private OnLogoItemClick mOnLogoItemClick;
 private OnIconSelectedListener mOnIconSelectedListener;

 /**
 * 设置点击事件
 * @param mOnLogoItemClick
 */
 public void addOnItemClick(OnLogoItemClick mOnLogoItemClick) {
 this.mOnLogoItemClick = mOnLogoItemClick;
 }

 /**
 * 到选中位置后选中事件接口
 */
 public interface OnIconSelectedListener{
 void onIconSelected( int pos);
 }

 /**
 * 设置点击事件
 * @param mOnIconSelectedListener
 */
 public void addOnIconSelectedListener(OnIconSelectedListener mOnIconSelectedListener) {
 this.mOnIconSelectedListener = mOnIconSelectedListener;
 }
 /**
 * 旋转圆盘
 */
 private void getCheck() {
 mStartAngle %= 360;
 setRotation(mStartAngle);
 //改变选中的icon的状态
 setSelectedIcon();

 }

 //改变选中的icon的状态
 private void setSelectedIcon() {
 if (select_icon_rect.left==0&&select_icon_rect.top==0){
 //fragment中onWindowFocusChanged会出现计算select_icon_rect.left和select_icon_rect.top等于0的情况，
 // 所以做下判断，如果为0则重新调用下计算方法
 getSelectIconReft();
 }
 for (int j =0;j

view.ringView_half_left.addOnIconSelectedListener { position ->
 // ToDo 根据postion从你的list中获取对应的选中的对象的bean类属性即可

 }

app:list_rh="@array/zodiac_list" 

<?xml version="1.0" encoding="utf-8"?>


 
 @drawable/zodiac_1
 @drawable/zodiac_2
 @drawable/zodiac_3
 @drawable/zodiac_4
 @drawable/zodiac_5
 @drawable/zodiac_6
 @drawable/zodiac_7
 @drawable/zodiac_8
 @drawable/zodiac_9
 @drawable/zodiac_10
 @drawable/zodiac_11
 @drawable/zodiac_12