日历和PagerAdapter – 无限视图

在我的活动中,我使用ViewPager向左/向右滑动并相应地显示月份视图。 我将onCreate的月份和年份值传递给PagerAdapter:

 private static int NUM_AWESOME_VIEWS = 3; viewPager = (ViewPager) v.findViewById(R.id.pager); cAdapter = new CalendarPagerAdapter(this.getActivity().getApplicationContext(), date_value, fragmentManager, month, year); viewPager.setAdapter(cAdapter); viewPager.setOffscreenPageLimit(3); 

日历从十一月开始,然后滚动到一月。 我希望日历向前和向后显示无限的意见。

PagerAdapter:

 public CalendarPagerAdapter(Context context, int dv, FragmentManager fm, int month, int year){ this.context = context; this.dv = dv; this.fm = fm; this.month = month; this.year = year; } public Object instantiateItem(View collection, int position) { Log.d("Object", "Instantiated"); LayoutInflater inflater = (LayoutInflater) collection.getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); View v = inflater.inflate(R.layout.simple_calendar_view, null); _calendar.set(Calendar.MONTH, month); _calendar.set(Calendar.YEAR, year); month = _calendar.get(Calendar.MONTH) + 1; year = _calendar.get(Calendar.YEAR); currentMonth = (Button) v.findViewById(R.id.currentMonth); currentMonth.setText(hijri.getMonthForInt(month-1).toUpperCase() + " " + year); calendarView = (GridView) v.findViewById(R.id.calendar); calendarWeek = (GridView) v.findViewById(R.id.calendarweek); calendarWeek.setAdapter(new CalendarWeekAdapter(context, firstDay)); // Initialised adapter = new GridCellAdapter(calendarView, context, R.id.calendar_day_gridcell, month, year, 0, 0, 0); adapter.notifyDataSetChanged(); calendarView.setAdapter(adapter); ((ViewPager) collection).addView(v, 0); return v; } 

基于乔恩·威利斯的代码 ,这是我想出来的,但是当viewpager的位置是0或2,页面变成空白,然后显示下一个月+ 1(也就是说,滚动一月后,页面闪烁并显示三月)。 它不会顺利滚动。 我不知道该怎么做。

  viewPager.setOnPageChangeListener(new OnPageChangeListener() { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageScrollStateChanged(int state) { if (state == ViewPager.SCROLL_STATE_IDLE) Log.d("Calendar ViewPager", "Calendar ViewPager" + viewPager.getCurrentItem()); if (focusedPage == 0) { _calendar.add(Calendar.MONTH, -1); month = _calendar.get(Calendar.MONTH); year = _calendar.get(Calendar.YEAR); setGridCellAdapter(context, month, year); } else if (focusedPage == 2) { _calendar.add(Calendar.MONTH, +1); month = _calendar.get(Calendar.MONTH); year = _calendar.get(Calendar.YEAR); setGridCellAdapter(context, month, year); } viewPager.setCurrentItem(1, false); } } @Override public void onPageSelected(int position) { focusedPage = position; } }); public void setGridCellAdapter(Context ctx, int month, int year) { cAdapter = new CalendarPagerAdapter(ctx, date_value, fragmentManager, month, year); Log.d("Object", "Re-instantiatted" + month + year); cAdapter.notifyDataSetChanged(); viewPager.setAdapter(cAdapter); } 

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我已经实现了这一点,但并不完美通过使用每个页面作为3个片段。 当用户向右或向左快速移动时,它将会回到中间并更新每个片段的新数据源。

在主要

 MonthViewContentFragment[] fragList = new MonthViewContentFragment[3]; fragList[0] = MonthViewContentFragment.newInstance(prevMonth); fragList[1] = MonthViewContentFragment.newInstance(currentMonth); fragList[2] = MonthViewContentFragment.newInstance(nextMonth); ViewPager monthPage = (ViewPager) v.findViewById(R.id.monthview_content); MonthPageAdapter monthPageAdapter = new MonthPageAdapter(getFragmentManager(), fragList); monthPage.setAdapter(monthPageAdapter); monthPage.setOnPageChangeListener(this); monthPage.setCurrentItem(1, false); 

onPageScrollStateChanged

 if (state == ViewPager.SCROLL_STATE_IDLE) { if (focusPage < PAGE_CENTER) { currentMonth.add(Calendar.MONTH, -1); } else if (focusPage > PAGE_CENTER) { currentMonth.add(Calendar.MONTH, 1); } monthPageAdapter.setCalendar(currentMonth); monthPage.setCurrentItem(1, false); updateTitle(); } 

onPageSelected

 public void onPageSelected(int position) { // TODO Auto-generated method stub focusPage = position; } 

在MonthPageAdapter中

  MonthViewContentFragment[] fragList; MonthViewContentFragment temp; int fragNumber = 3; public MonthPageAdapter(FragmentManager fm, MonthViewContentFragment[] fragList) { super(fm); this.fragList = fragList; } @Override public int getItemPosition(Object object) { // TODO Auto-generated method stub return POSITION_NONE; } @Override public Fragment getItem(int position) { return fragList[position]; } @Override public int getCount() { return 3; } public void setCalendar(Calendar currentMonth) { Calendar prevMonth = Calendar.getInstance(); prevMonth.setTime(currentMonth.getTime()); prevMonth.add(Calendar.MONTH, -1); Calendar nextMonth = Calendar.getInstance(); nextMonth.setTime(currentMonth.getTime()); nextMonth.add(Calendar.MONTH, 1); //update all 3 fragments fragList[0].updateUI(prevMonth); fragList[1].updateUI(currentMonth); fragList[2].updateUI(nextMonth); } 

在MonthViewContentFragment中

  @Override public void updateUI(Calendar monthYear) { View v = getView(); if (v == null) return; //setNewDataSource calcurate new List<String> date calendarViewAdapter.setNewDataSource(monthYear); calendarViewAdapter.notifyDataSetChanged(); } 

这是不完美的,因为当用户快速。 滚动不会改变为空闲,然后ViewPager达到其结束。

我不知道我明白这一点(从来没有使用这个viewPager,总是使用另一个Horizo​​ntalViewSlider),但是对于你的onPageScrollStateChanged()为什么你有一个特殊的情况focusPage == 0和focusedPage == 2?

如果没有什么特别的1月和3月,可能会删除onPageScrollStateChanged()内的一切?

我的猜测是闪烁是从你调用setGridCellAdapter()的时候,因为这将刷新页面调用notifyDataSetChanged。