Android实现弧形菜单效果

public class HomePageMenuLayout extends ViewGroup {
 private Context context;
 // 菜单项的文本
 private String[] mItemTexts = null;
 private int StatusHeight;//状态栏高度
 public HomePageMenuLayout(Context context,AttributeSet attrs) {
 super(context,attrs);
 this.context = context;
 StatusHeight = ScreenUtils.getStatusHeight(context);
 }
 /**
 * 设置布局的宽高，并策略menu item宽高
 */
 int resWidth = 0;
 int resHeight = 0;
 int mRadius = 0;
 @Override
 protected void onMeasure(int widthMeasureSpec,int heightMeasureSpec) {
 //布局宽高尺寸设置为屏幕尺寸
 //设置该布局的大小
 setMeasuredDimension(widthMeasureSpec,heightMeasureSpec);
 /**
 * 根据传入的参数，分别获取测量模式和测量值
 */
 int width = MeasureSpec.getSize(widthMeasureSpec);
 resHeight = MeasureSpec.getSize(heightMeasureSpec);
 resWidth = MeasureSpec.getSize(widthMeasureSpec);
 // 获得半径
 mRadius = (int) (resHeight / 2 - 2 * StatusHeight);
 //设置item尺寸
 int childSize = (int) (mRadius * 1 / 2);
 // menu item测量模式--精确模式
 int childMode = MeasureSpec.EXACTLY;
 for (int i = 0; i < getChildCount(); i++) {
 final View child = getChildAt(i);
 if (child.getVisibility() == GONE) {
 continue;
 }
 // 计算menu item的尺寸；以及和设置好的模式，去对item进行测量
 int makeMeasureSpec = -1;
 makeMeasureSpec = MeasureSpec.makeMeasureSpec(childSize,childMode);
 child.measure(makeMeasureSpec,makeMeasureSpec);
 }
 }
 /**
 * item布局的角度
 */
 private int[] widthall = null;
 /**
 * 设置Item的位置：第一个参数1：该参数指出当前ViewGroup的尺寸或者位置是否发生了改变
 * 2.当期绘图光标横坐标位置
 * 3.当前绘图光标纵坐标位置
 */
 @Override
 protected void onLayout(boolean changed,int l,int t,int r,int b) {
 int left,top;
 int cWidth = (int) (mRadius * 1 / 2);
 final int childCount = getChildCount();
 // 计算，中心点到menu item中心的距离
 float tmp = mRadius - cWidth / 2;
 // 遍历去设置menuitem的位置
 for (int i = 0; i < childCount; i++) {
 final View child = getChildAt(i);
 if (child.getVisibility() == GONE) {
 continue;
 }
 left = (int) (mRadius * Math.cos(Math.toRadians(widthall[i]))) - 65;
 top = (int) (mRadius - (resHeight / 2 - 2 * StatusHeight) * Math.sin(Math.toRadians(widthall[i])) - StatusHeight);
 child.layout(left,top,left + cWidth,top + cWidth);
 }
 }
 public interface OnMenuItemClickListener {
 void itemClick(View view,int pos);
 }
 public void setOnMenuItemClickListener(
 OnMenuItemClickListener mOnMenuItemClickListener) {
 this.mOnMenuItemClickListener = mOnMenuItemClickListener;
 }
 // 菜单的个数
 private int mMenuItemCount;
 /**
 * 设置菜单条目的图标和文本
 */
 public void setMenuItemIconsAndTexts(String[] mItemTexts) {
 this.mItemTexts = mItemTexts;
 this.mMenuItemCount = mItemTexts.length;
 resultAngle();
 addMenuItems();
 }
 private void resultAngle() {
 switch (this.mMenuItemCount) {
 case 3:
 widthall = Constants.ITEM3;
 break;
 case 4:
 widthall = Constants.ITEM4;
 break;
 case 5:
 widthall = Constants.ITEM5;
 break;
 case 6:
 widthall = Constants.ITEM6;
 break;
 case 7:
 widthall = Constants.ITEM7;
 break;
 case 8:
 widthall = Constants.ITEM8;
 break;
 case 9:
 widthall = Constants.ITEM9;
 break;
 case 10:
 widthall = Constants.ITEM10;
 break;
 default:
 break;
 }
 }
 /**
 * 设置菜单条目的图标和文本
 */
 public void setMenuItemIconsAndTexts() {
 addMenuItems();
 }
 private int mMenuItemLayoutId = R.layout.homepage_item_layout;
 /**
 * MenuItem的点击事件接口
 */
 private OnMenuItemClickListener mOnMenuItemClickListener;
 private float yPosition = 0;
 /**
 * 添加菜单项
 */
 private void addMenuItems() {
 LayoutInflater mInflater = LayoutInflater.from(getContext());
 /**
 * 根据用户设置的参数，初始化view
 */
 for (int i = 0; i < mMenuItemCount; i++) {
 final int j = i;
 View view = mInflater.inflate(mMenuItemLayoutId,this,false);

 final ImageView iv = (ImageView) view
  .findViewById(R.id.homepage_pager1_item_img);
 final TextView tv = (TextView) view
  .findViewById(R.id.homepage_pager1_item_tv);
 if (iv != null) {
 iv.setImageResource(R.mipmap.menu_ture);
 }
 if (tv != null) {
 tv.setText(mItemTexts[i]);
 }
 view.findViewById(R.id.homepage_item_layout).setOnClickListener(new OnClickListener() {
 @Override
 public void onClick(View v) {}
 });
 view.findViewById(R.id.homepage_item_layout).setOnTouchListener(new OnTouchListener() {
 @Override
 public boolean onTouch(View v,MotionEvent event) {
  if (event.getAction() == MotionEvent.ACTION_DOWN) {
  yPosition = event.getY();//获取按下的位置
  iv.setImageResource(R.mipmap.menu);
  } else if (event.getAction() == MotionEvent.ACTION_UP) {
  iv.setImageResource(R.mipmap.menu_ture);
  float displacement = Math.abs(yPosition - event.getY());
  //精确按下的位置做出响应
  if (mOnMenuItemClickListener != null&&displacement<25) {
  mOnMenuItemClickListener.itemClick(v,j);
  }
  } else if (event.getAction() == MotionEvent.ACTION_CANCEL || event.getAction() == MotionEvent.ACTION_POINTER_UP) {
  iv.setImageResource(R.mipmap.menu_ture);
  }
  return true;
 }
 });
 addView(view);
 }
 }
}