SwitchButton自定义开关

public class SwitchButton extends CheckBox {
   private Paint mPaint;
   private RectF mSaveLayerRectF;
   private float mFirstDownY;
   private float mFirstDownX;
   private int mClickTimeout;
   private int mTouchSlop;
   private final int MAX_ALPHA = 255;
   private int mAlpha = MAX_ALPHA;
   private boolean mChecked = false;
   private boolean mBroadcasting;// 标示是否正在执行监听事件中
   private boolean mTurningOn;// 标示位置是否达到开启状态
   private PerformClick mPerformClick;
   private OnCheckedChangeListener mOnCheckedChangeListener;
   private OnCheckedChangeListener mOnCheckedChangeWidgetListener;
   private boolean mAnimating;// 标示是否继续执行移动动画
   private final float VELOCITY = 350;// 定义按钮动画移动的最大长度
   private float mVelocity;// 按钮动画移动的最大像素长度
   private float mAnimationPosition;// 按钮动画移动的当前位置
   private float mAnimatedVelocity;// 按钮动画移动的实际位移(+mVelocity/-mVelocity)
   private Bitmap bmBgGreen;// 绿色背景
   private Bitmap bmBgWhite;// 白色背景
   private Bitmap bmBtnNormal;// 未按下时按钮
   private Bitmap bmBtnPressed;// 按下时按钮
   private Bitmap bmCurBtnPic;// 当前显示的按钮图片
   private Bitmap bmCurBgPic;// 当前背景图片
   private float bgWidth;// 背景宽度
   private float bgHeight;// 背景宽度
   private float btnWidth;// 按钮宽度
   private float offBtnPos;// 按钮关闭时位置
   private float onBtnPos;// 按钮开启时位置
   private float curBtnPos;// 按钮当前位置
   private float startBtnPos;// 开始按钮位置
   private final int COMMON_WIDTH_IN_PIXEL = 225;// 默认宽度
   private final int COMMON_HEIGHT_IN_PIXEL = 115;// 默认高度

   public SwitchButton(Context context, AttributeSet attrs) {
      this(context, attrs, android.R.attr.checkboxStyle);
   }

   public SwitchButton(Context context) {
      this(context, null);
   }

   public SwitchButton(Context context, AttributeSet attrs, int defStyle) {
      super(context, attrs, defStyle);
      init(context, attrs);
   }

   private void init(Context context, AttributeSet attrs) {
      mPaint = new Paint();
      mPaint.setColor(Color.WHITE);
      Resources resources = context.getResources();

      // get attrConfiguration
      TypedArray array = context.obtainStyledAttributes(attrs,
            R.styleable.SwitchButton);
      int width = (int) array.getDimensionPixelSize(
            R.styleable.SwitchButton_bmWidth, 0);
      int height = (int) array.getDimensionPixelSize(
            R.styleable.SwitchButton_bmHeight, 0);
      array.recycle();

      // size width or height
      if (width <= 0 || height <= 0) {
         width = COMMON_WIDTH_IN_PIXEL;
         height = COMMON_HEIGHT_IN_PIXEL;
      } else {
         float scale = (float) COMMON_WIDTH_IN_PIXEL
               / COMMON_HEIGHT_IN_PIXEL;
         if ((float) width / height > scale) {
            width = (int) (height * scale);
         } else if ((float) width / height < scale) {
            height = (int) (width / scale);
         }
      }

      // get viewConfiguration
      mClickTimeout = ViewConfiguration.getPressedStateDuration()
            + ViewConfiguration.getTapTimeout();
      mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();

      // get Bitmap
      bmBgGreen = BitmapFactory.decodeResource(resources,
            R.mipmap.switch_btn_bg_on);
      bmBgWhite = BitmapFactory.decodeResource(resources,
            R.mipmap.switch_btn_bg_off);
      bmBtnNormal = BitmapFactory.decodeResource(resources,
            R.mipmap.switch_btn_normal);
      bmBtnPressed = BitmapFactory.decodeResource(resources,
            R.mipmap.switch_btn_pressed);

      // size Bitmap
      bmBgGreen = Bitmap.createScaledBitmap(bmBgGreen, width, height, true);
      bmBgWhite = Bitmap.createScaledBitmap(bmBgWhite, width, height, true);
      bmBtnNormal = Bitmap.createScaledBitmap(bmBtnNormal, height, height,
            true);
      bmBtnPressed = Bitmap.createScaledBitmap(bmBtnPressed, height, height,
            true);

      bmCurBtnPic = bmBtnPressed;// 初始按钮图片
//    bmCurBtnPic = mChecked ? bmBtnPressed : bmBtnNormal;// 初始按钮图片
      bmCurBgPic = mChecked ? bmBgGreen : bmBgWhite;// 初始背景图片
      bgWidth = bmBgGreen.getWidth();// 背景宽度
      bgHeight = bmBgGreen.getHeight();// 背景高度
      btnWidth = bmBtnNormal.getWidth();// 按钮宽度
      offBtnPos = 0;// 关闭时在最左边
      onBtnPos = bgWidth - btnWidth;// 开始时在右边
      curBtnPos = mChecked ? onBtnPos : offBtnPos;// 按钮当前为初始位置

      // get density
      float density = resources.getDisplayMetrics().density;
      mVelocity = (int) (VELOCITY * density + 0.5f);// 动画距离
      mSaveLayerRectF = new RectF(0, 0, bgWidth, bgHeight);
   }

   @Override
   public void setEnabled(boolean enabled) {
      mAlpha = enabled ? MAX_ALPHA : MAX_ALPHA / 3;
      super.setEnabled(enabled);
   }

   public boolean isChecked() {
      return mChecked;
   }

   public void toggle() {
      setChecked(!mChecked);
   }

   private void setCheckedDelayed(final boolean checked) {
      postDelayed(new Runnable() {
         @Override
         public void run() {
            setChecked(checked);
         }
      }, 10);
   }

   public void setChecked(boolean checked) {
      if (mChecked != checked) {
         mChecked = checked;

         // 初始化按钮位置
         curBtnPos = checked ? onBtnPos : offBtnPos;
         // 改变背景图片
         bmCurBgPic = checked ? bmBgGreen : bmBgWhite;
         bmCurBtnPic = checked ? bmBtnNormal : bmBtnPressed;
         invalidate();

         if (mBroadcasting) {
            // NO-OP
            return;
         }
         // 正在执行监听事件
         mBroadcasting = true;
         if (mOnCheckedChangeListener != null) {
            mOnCheckedChangeListener.onCheckedChanged(SwitchButton.this,
                  mChecked);
         }
         if (mOnCheckedChangeWidgetListener != null) {
            mOnCheckedChangeWidgetListener.onCheckedChanged(
                  SwitchButton.this, mChecked);
         }
         // 监听事件结束
         mBroadcasting = false;
      }
   }

   public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {
      mOnCheckedChangeListener = listener;
   }

   void setOnCheckedChangeWidgetListener(OnCheckedChangeListener listener) {
      mOnCheckedChangeWidgetListener = listener;
   }

   @Override
   public boolean onTouchEvent(MotionEvent event) {
      int action = event.getAction();
      float x = event.getX();
      float y = event.getY();
      float deltaX = Math.abs(x - mFirstDownX);
      float deltaY = Math.abs(y - mFirstDownY);
      switch (action) {
      case MotionEvent.ACTION_DOWN:
         ViewParent mParent = getParent();
         if (mParent != null) {
            // 通知父控件不要拦截本view的触摸事件
            mParent.requestDisallowInterceptTouchEvent(true);
         }
         mFirstDownX = x;
         mFirstDownY = y;
         bmCurBtnPic = bmBtnPressed;
         startBtnPos = mChecked ? onBtnPos : offBtnPos;
         break;
      case MotionEvent.ACTION_MOVE:
         float time = event.getEventTime() - event.getDownTime();
         curBtnPos = startBtnPos + event.getX() - mFirstDownX;
         if (curBtnPos >= onBtnPos) {
            curBtnPos = onBtnPos;
         }
         if (curBtnPos <= offBtnPos) {
            curBtnPos = offBtnPos;
         }
         mTurningOn = curBtnPos > bgWidth / 2 - btnWidth / 2;
         break;
      case MotionEvent.ACTION_UP:
         bmCurBtnPic = bmBtnNormal;
         time = event.getEventTime() - event.getDownTime();
         if (deltaY < mTouchSlop && deltaX < mTouchSlop
               && time < mClickTimeout) {
            if (mPerformClick == null) {
               mPerformClick = new PerformClick();
            }
            if (!post(mPerformClick)) {
               performClick();
            }
         } else {
            startAnimation(mTurningOn);
         }
         break;
      }
      invalidate();
      return isEnabled();
   }

   private class PerformClick implements Runnable {
      public void run() {
         performClick();
      }
   }

   @Override
   public boolean performClick() {
      startAnimation(!mChecked);
      return true;
   }

   @Override
   protected void onDraw(Canvas canvas) {
      canvas.saveLayerAlpha(mSaveLayerRectF, mAlpha, Canvas.MATRIX_SAVE_FLAG
            | Canvas.CLIP_SAVE_FLAG | Canvas.HAS_ALPHA_LAYER_SAVE_FLAG
            | Canvas.FULL_COLOR_LAYER_SAVE_FLAG
            | Canvas.CLIP_TO_LAYER_SAVE_FLAG);

      // 绘制底部图片
      canvas.drawBitmap(bmCurBgPic, 0, 0, mPaint);

      // 绘制按钮
      canvas.drawBitmap(bmCurBtnPic, curBtnPos, 0, mPaint);

      canvas.restore();
   }

   @Override
   protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
      setMeasuredDimension((int) bgWidth, (int) bgHeight);
   }

   private void startAnimation(boolean turnOn) {
      mAnimating = true;
      mAnimatedVelocity = turnOn ? mVelocity : -mVelocity;
      mAnimationPosition = curBtnPos;
      new SwitchAnimation().run();
   }

   private void stopAnimation() {
      mAnimating = false;
   }

   private final class SwitchAnimation implements Runnable {
      @Override
      public void run() {
         if (!mAnimating) {
            return;
         }
         doAnimation();
         requestAnimationFrame(this);
      }
   }

   private void doAnimation() {
      mAnimationPosition += mAnimatedVelocity * ANIMATION_FRAME_DURATION
            / 1000;
      if (mAnimationPosition <= offBtnPos) {
         stopAnimation();
         mAnimationPosition = offBtnPos;
         setCheckedDelayed(false);
      } else if (mAnimationPosition >= onBtnPos) {
         stopAnimation();
         mAnimationPosition = onBtnPos;
         setCheckedDelayed(true);
      }
      curBtnPos = mAnimationPosition;
      invalidate();
   }

   private static final int MSG_ANIMATE = 1000;
   public static final int ANIMATION_FRAME_DURATION = 1000 / 60;

   public void requestAnimationFrame(Runnable runnable) {
      Message message = new Message();
      message.what = MSG_ANIMATE;
      message.obj = runnable;
      mHandler.sendMessageDelayed(message, ANIMATION_FRAME_DURATION);
   }

   private Handler mHandler = new Handler() {
      public void handleMessage(Message m) {
         switch (m.what) {
         case MSG_ANIMATE:
            if (m.obj != null) {
               ((Runnable) m.obj).run();
            }
            break;
         }
      }
   };
}

style：

name="SwitchButton">
    name="bmWidth" format="dimension"/>
    name="bmHeight" format="dimension"/>

图片文件就不上传了