弧形菜單(Android)
前言：公司需求，自己寫的一個弧形菜單！
效果：
開發環境：AndroidStudio2.2.1+gradle-2.14.1
涉及知識：1.自定義控件，2.事件分發等
部分代碼：
public class HomePageMenuLayout extends ViewGroup { private Context context; // 菜單項的文本 private String[] mItemTexts = null; private int StatusHeight;//狀態欄高度 public HomePageMenuLayout(Context context, AttributeSet attrs) { super(context, attrs); this.context = context; StatusHeight = ScreenUtils.getStatusHeight(context); } /** * 設置布局的寬高，並策略menu item寬高 */ int resWidth = 0; int resHeight = 0; int mRadius = 0; @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { //布局寬高尺寸設置為屏幕尺寸 //設置該布局的大小 setMeasuredDimension(widthMeasureSpec, heightMeasureSpec); /** * 根據傳入的參數，分別獲取測量模式和測量值 */ int width = MeasureSpec.getSize(widthMeasureSpec); resHeight = MeasureSpec.getSize(heightMeasureSpec); resWidth = MeasureSpec.getSize(widthMeasureSpec); // 獲得半徑 mRadius = (int) (resHeight / 2 - 2 * StatusHeight); //設置item尺寸 int childSize = (int) (mRadius * 1 / 2); // menu item測量模式--精確模式 int childMode = MeasureSpec.EXACTLY; for (int i = 0; i < getChildCount(); i++) { final View child = getChildAt(i); if (child.getVisibility() == GONE) { continue; } // 計算menu item的尺寸；以及和設置好的模式，去對item進行測量 int makeMeasureSpec = -1; makeMeasureSpec = MeasureSpec.makeMeasureSpec(childSize, childMode); child.measure(makeMeasureSpec, makeMeasureSpec); } } /** * item布局的角度 */ private int[] widthall = null; /** * 設置Item的位置：第一個參數1：該參數指出當前ViewGroup的尺寸或者位置是否發生了改變 * 2.當期繪圖光標橫坐標位置 * 3.當前繪圖光標縱坐標位置 */ @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(); // 計算，中心點到menu item中心的距離 float tmp = mRadius - cWidth / 2; // 遍歷去設置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; } // 菜單的個數 private int mMenuItemCount; /** * 設置菜單條目的圖標和文本 */ 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; } } /** * 設置菜單條目的圖標和文本 */ public void setMenuItemIconsAndTexts() { addMenuItems(); } private int mMenuItemLayoutId = R.layout.homepage_item_layout; /** * MenuItem的點擊事件接口 */ private OnMenuItemClickListener mOnMenuItemClickListener; private float yPosition = 0; /** * 添加菜單項 */ private void addMenuItems() { LayoutInflater mInflater = LayoutInflater.from(getContext()); /** * 根據用戶設置的參數，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();//獲取按下的位置 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()); //精確按下的位置做出響應 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); } } }