public interface PageCarver {
 
  void drawPage(Canvas canvas, int index);//繪制頁(yè)內(nèi)容
  Integer requestPrePage();//請(qǐng)求翻到上一頁(yè)
  Integer requestNextPage();//請(qǐng)求翻到下一頁(yè)
  void requestInvalidate();//刷新界面
  Integer getCurrentPageIndex();//獲取當(dāng)前頁(yè)

  /**
   * 開(kāi)始動(dòng)畫(huà)的回調(diào)
   *
   * @param isCancel 是否是取消動(dòng)畫(huà)
   */
  void onStartAnim(boolean isCancel);

  /**
   * 結(jié)束動(dòng)畫(huà)的回調(diào)
   *
   * @param isCancel 是否是取消動(dòng)畫(huà)
   */
  void onStopAnim(boolean isCancel);
 }

public abstract class BaseReaderView extends View implements PageAnimController.PageCarver{

 /**
  * 將View的繪制事件傳送給 PageAnimController 實(shí)現(xiàn)動(dòng)畫(huà)繪制過(guò)程中
  * @param canvas
  * @return
  */
 @Override
 protected void onDraw(Canvas canvas) {
  if (pageAnimController == null || !pageAnimController.dispatchDrawPage(canvas, this)) {
   drawPage(canvas, currentPageIndex);
  }
 }
 
 /**
  * 將View的觸摸事件傳送給 PageAnimController 以便實(shí)現(xiàn)翻頁(yè)動(dòng)畫(huà) 
  * @param event
  * @return
  */
 @Override
 public boolean onTouchEvent(MotionEvent event) {
  pageAnimController.dispatchTouchEvent(event, this);
  return true;
 }
}

/**
 * <p>
 * 頁(yè)面快照，用來(lái)存儲(chǔ)閱讀器每一頁(yè)的內(nèi)容
 *
 * @author cpacm 2017/10/9
 */

public class PageSnapshot {
 private int pageIndex;
 private Bitmap mBitmap;
 private Canvas mCanvas;

 public Canvas beginRecording(int width, int height) {
  if (mBitmap == null) {
   mBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_4444);
   mCanvas = new Canvas(mBitmap);
  } else {
   mCanvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
  }
  return mCanvas;
 }

 public void draw(Canvas canvas) {
  if (null != mBitmap) {
   canvas.drawBitmap(mBitmap, 0, 0, null);
  }
 }

 public void destroy() {
  if (mBitmap != null && !mBitmap.isRecycled()) {
   mBitmap.recycle();
   mBitmap = null;
  }
 }
}

 //摘自 PageElement 的 onDraw 方法
 @Override
 public void draw(Canvas canvas) {
  int index = drawPageIndex - startPageIndex;
  if (index < 0 || index >= pages.size()) return;
  BookPageData bookPageData = pages.get(index);
  int offsetX = bookSettingParams.paddingLeft;
  int offsetY = bookSettingParams.paddingTop;
  if (bookPageData == null) return;
  canvas.drawColor(bookSettingParams.getBgColor());
  bookHeaderElement.setChapterTitle(bookPageData.getChapterName());
  bookHeaderElement.setX(offsetX);
  bookHeaderElement.setY(offsetY);
  if (bookPageData.isChapterFirstPage()) {
   bookHeaderElement.drawFirstPage(canvas);
  } else {
   bookHeaderElement.draw(canvas);
  }

  bookFooterElement.setProgress(bookPageData.getPageIndex(), bookPageData.getPageNums());
  bookFooterElement.setX(offsetX);
  bookFooterElement.setY(offsetY + getHeight() - bookFooterElement.getHeight());
  bookFooterElement.draw(canvas);

  for (int i = 0; i < bookPageData.getDataList().size(); i++) {
   BookData bookData = bookPageData.getDataList().get(i);
   if (bookData instanceof BookLineData) {
    BookLineData bookLineData = (BookLineData) bookData;
    bookLineElement.setLineText(bookLineData.getContent());
    bookLineElement.setX(bookLineData.getPosition().x);
    bookLineElement.setY(bookLineData.getPosition().y);
    bookLineElement.drawWithDigests(canvas, bookLineData, bookReaderView.getCurrentDigests(index));
    //bookLineElement.draw(canvas);
   } else if (bookData instanceof BookImageData) {
    BookImageData bookImageData = (BookImageData) bookData;
    bookImageElement.setX(bookImageData.getPosition().x);
    bookImageElement.setY(bookImageData.getPosition().y);
    bookImageElement.syncDrawWithinBitmap(canvas, bookImageData, bookReaderView.getCacheBitmap(drawPageIndex));
   }
  }
 }

/**
 * <p>
 * 章節(jié)緩存構(gòu)成方案如下：
 * | -6,-5,-4,-3,-2,-1,0 | 1,2,3,4,5,6,7,8,9 | 10,11,12,13,14,15 | = pages
 * | cacheChapter1 | cacheChapter2 | cacheChapter3 |
 * startPageIndex = pageIndex:-6 endPageIndex = pageIndex:16
 * currentChapterStartIndex => pageIndex:1 => pages[7]
 * currentChapterEndIndex => pageIndex:10 => pages[16]
 * </p>
 */

// TextSelectorElement 上的觸摸分發(fā)方法
public boolean dispatchTouchEvent(final MotionEvent ev) {
 int key = ev.getAction();
 currentTouchPoint.set(ev.getX(), ev.getY());
 switch (key) {
  case MotionEvent.ACTION_DOWN:
   isPressInvalid = false;
   hasConsume = true;
   isDown = true;
   mTouchDownPoint.set(ev.getX(), ev.getY());
   // 該方法中會(huì)記錄isBookDigestDown的值
   checkIsPressDigests(ev.getX(), ev.getY());
   //判斷是否處于選擇模式
   if (!isSelect) {
    if (isBookDigestDown == 0) {
     postLongClickPerform(0);//提交長(zhǎng)按時(shí)間
    }
   } else {
    // 判斷是否觸摸到選擇光標(biāo)上，若是則可以拖動(dòng)光標(biāo)移動(dòng)
    checkCurrentMoveCursor(ev);
   }
   break;
  case MotionEvent.ACTION_MOVE:
   float move = PointF.length(ev.getX() - mTouchDownPoint.x, ev.getY() - mTouchDownPoint.y);
   if (move > moveSlop) {
    isPressInvalid = true;
   }
   if (isPressInvalid) {
    removeLongPressPerform();
    if (isSelect) {
     // 關(guān)閉彈窗（包括筆記編輯框等）
     onCloseView();
     // 移動(dòng)光標(biāo)
     onMove(ev);
    } else {
     //未處于選擇模式下，相當(dāng)于一個(gè)普通的點(diǎn)擊事件
     onPress(ev);
    }
   }
   break;
  case MotionEvent.ACTION_UP:
   hasConsume = false;
   removeLongPressPerform();
   if (isSelect) {
    // -1 表示為未觸摸到光標(biāo)
    if (moveCursor == -1) {
     // 取消選擇模式
     setSelect(false);
     hasConsume = true;
    } else {
     //停止移動(dòng)時(shí)，會(huì)打開(kāi)筆記生成彈框
     onOpenDigestsView();
    }
    moveCursor = -1;
   } else {
    if (isBookDigestDown == 1) {
     onOpenNoteView();
     hasConsume = true;
    } else if (isBookDigestDown == 2) {
     onOpenEditView();
     hasConsume = true;
    } else {
     // 模擬成一個(gè)普通的點(diǎn)擊事件，會(huì)取消當(dāng)前的選擇模式
     onPress(ev);
    }
   }
   invalidate();
   break;
  case MotionEvent.ACTION_CANCEL:
   hasConsume = false;
   removeLongPressPerform();
   break;
  default:
   break;
 }
 // 判斷選擇器是否消耗了當(dāng)前事件
 return hasConsume || isSelect;
}

// 摘自 PageElement 下的設(shè)置屬性變化方法
// BookSettingParams 即為記錄閱讀器設(shè)置屬性的輔助類(lèi)
@Override
public void update(ReaderSettingParams params) {
  bookSettingParams = (BookSettingParams) params;
  bookHeaderElement.update(bookSettingParams);
  bookFooterElement.update(bookSettingParams);
  bookLineElement.update(bookSettingParams);
  bookImageElement.update(bookSettingParams);

  initPageElement();
}

/**
 * <p>
 * 聽(tīng)書(shū)tts播放模組
 *
 * @author cpacm 2017/12/13
 */

public class BookSpeechElement extends ResElement implements SynthesizerListener {

  // .... 省略部分代碼
  
  // 從每一頁(yè)數(shù)據(jù) PageData 中的 LineData 列表中獲取要繪制的區(qū)域
  private void updateDrawRect(int startPos, int endPos) {
    if (endPos <= offsetPosition || endPos == this.endPos) return;
    this.endPos = endPos;
    this.tempPos = startPos;
    int s = this.startPos + startPos + bookPageData.getStartPos() - offsetPosition;
    int e = this.startPos + endPos + bookPageData.getStartPos() - offsetPosition;
    drawRect.clear();
    for (BookLineData line : lineData) {
      if (line.startPos > e || line.endPos <= s) continue;
      if (line.startPos <= s && line.endPos <= e) {
        Rect startRect = line.getCharArea().get(s);
        Rect endRect = line.getCharArea().get(line.endPos - 1);
        Rect rect = new Rect(startRect.left, startRect.top, endRect.right, endRect.bottom);
        drawRect.add(rect);
      }
      if (line.startPos > s && line.endPos <= e) {
        Rect startRect = line.getCharArea().get(line.startPos);
        Rect endRect = line.getCharArea().get(line.endPos - 1);
        Rect rect = new Rect(startRect.left, startRect.top, endRect.right, endRect.bottom);
        drawRect.add(rect);
      }
      if (line.startPos > s && line.endPos > e) {
        Rect startRect = line.getCharArea().get(line.startPos);
        Rect endRect = line.getCharArea().get(e);
        Rect rect = new Rect(startRect.left, startRect.top, endRect.right, endRect.bottom);
        drawRect.add(rect);
      }
      if (line.startPos <= s && line.endPos > e) {
        Rect startRect = line.getCharArea().get(s);
        Rect endRect = line.getCharArea().get(e);
        Rect rect = new Rect(startRect.left, startRect.top, endRect.right, endRect.bottom);
        drawRect.add(rect);
      }
    }
    // 刷新當(dāng)前書(shū)頁(yè)
    bookReaderView.flashCurrentPageSnapshot();
  }


  @Override
  public void draw(Canvas canvas) {
    if (!isSpeaking()) return;
    for (Rect rect : drawRect) {
      canvas.drawLine(rect.left, rect.bottom, rect.right, rect.bottom, paint);
    }
  }

  @Override
  public void destroy() {
    exitTts();
  }
  
  /*################## 語(yǔ)音合成的回調(diào) ###################*/
  @Override
  public void onSpeakBegin() {}

  @Override
  public void onBufferProgress(int progress, int beginPos, int endPos, String info) { }

  @Override
  public void onSpeakPaused() {}

  @Override
  public void onSpeakResumed() {}

  @Override
  public void onSpeakProgress(int progress, int beginPos, int endPos) {
    // 根據(jù)朗讀的進(jìn)度更新UI
    updateDrawRect(beginPos, endPos);
  }

  @Override
  public void onCompleted(SpeechError speechError) {}

  @Override
  public void onEvent(int i, int i1, int i2, Bundle bundle) {}
}