/**
  * 绘制日历
  *
  * @return
  */
 private ViewFlipper drawContent() {
   ViewFlipper content = new ViewFlipper(getContext());
   LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, 0, 7);
   content.setLayoutParams(params);
   // 初始化第一个日历
   firstCalendar =
       createLinearLayout(
           LinearLayout.VERTICAL, LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
   // 初始化第二个日历
   secondCalendar =
       createLinearLayout(
           LinearLayout.VERTICAL, LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
   // 设置默认日历为第一个日历
   currentCalendar = firstCalendar;
   // 加入ViewFlipper
   content.addView(firstCalendar);
   content.addView(secondCalendar);
   // 绘制线条框架
   drawFrame(firstCalendar);
   drawFrame(secondCalendar);
   return content;
 }