在 RecyclerView 适配器中显示错误的日期答案

【问题标题】：Displaying wrong date in RecyclerView Adapter在 RecyclerView 适配器中显示错误的日期
【发布时间】：2018-02-07 16:51:20
【问题描述】：

在比较两个日期后，我在消息上方显示日期。如果我显示每个项目的日期，它工作正常。但是当我试图显示Today、Yesterday 和date 时，它总是只显示date。这里的日期没有错，但是格式化日期出了点问题。

SimpleDateFormat simpleDateFormat = new SimpleDateFormat("MMM dd, yyyy hh:mm:ss");
    try {
        Date current_itemDate = simpleDateFormat.parse(chatMessage.getDateTime());

        DateFormat outputFormat = new SimpleDateFormat("hh:mm a");
        Date date = simpleDateFormat.parse(chatMessage.getDateTime());
        holder.timeTextView.setText(outputFormat.format(date));
        long previousTs = 0;
        if (position > 0) {
            ChatMessage pm = chatMessages.get(position - 1);
            previousTs = simpleDateFormat.parse(pm.getDateTime()).getTime();
        }
        setTimeTextVisibility(current_itemDate.getTime(), previousTs, holder.textViewTimePeriod,
                holder.dividerTop);

    } catch (ParseException e) {
        e.printStackTrace();
    }

下面提到了我使用的逻辑来显示TextView 的日期或日期。如果我做错了什么，请告诉我。

 private void setTimeTextVisibility(long now_tm, long msg_tm, TextView timeText, View dividerTop) {
    Calendar now_calendar = Calendar.getInstance();
    Calendar msg_calendar = Calendar.getInstance();
    now_calendar.setTimeInMillis(now_tm);
    msg_calendar.setTimeInMillis(msg_tm);
    boolean sameDay = now_calendar.get(Calendar.YEAR) == msg_calendar.get(Calendar.YEAR) &&
            now_calendar.get(Calendar.MONTH) == msg_calendar.get(Calendar.MONTH)
            && now_calendar.get(Calendar.DAY_OF_MONTH) == msg_calendar.get(Calendar.DAY_OF_MONTH);
    if (msg_tm == 0) {
        timeText.setVisibility(View.VISIBLE);
        dividerTop.setVisibility(View.VISIBLE);
        if (now_calendar.get(Calendar.DATE) == msg_calendar.get(Calendar.DATE)) {
            timeText.setText("Today");
        } else if (!sameDay) {
            timeText.setText("Yesterday");
        } else {
            timeText.setText("" + new SimpleDateFormat("dd MMM, yyyy").format(new Date(now_tm)));
        }
    } else {
        if (sameDay) {
            timeText.setVisibility(View.GONE);
            dividerTop.setVisibility(View.GONE);
            timeText.setText("");
        } else {
            timeText.setVisibility(View.VISIBLE);
            dividerTop.setVisibility(View.VISIBLE);
            timeText.setText("Today");
        }

    }
}

【问题讨论】：

标签： android datetime android-recyclerview

【解决方案1】：

在这里，我想向其他开发人员展示我们如何像 whatsapp 应用程序那样显示消息的前一天。

 private void setTimeTextVisibility(long now_tm, long msg_tm, TextView timeText, View dividerTop) {
    Date nowDate = new Date();
    nowDate.setTime(now_tm);
    Date msgDate = new Date();
    msgDate.setTime(msg_tm);
    Calendar now_calendar = Calendar.getInstance();
    now_calendar.setTimeInMillis(now_tm);
    Calendar now = Calendar.getInstance();
    Calendar msg_calendar = Calendar.getInstance();
    msg_calendar.setTimeInMillis(msg_tm);
    if (msg_tm == 0) {
        timeText.setVisibility(View.VISIBLE);
        dividerTop.setVisibility(View.VISIBLE);
        if (DateUtils.isToday(now_calendar.getTimeInMillis())) {
            timeText.setText("Today");
        } else if (now.get(Calendar.DATE) - now_calendar.get(Calendar.DATE) == 1) {
            timeText.setText("Yesterday");
        } else
            timeText.setText("" + new SimpleDateFormat("dd MMM, yyyy").format(new Date(now_tm)));
    } else {
        if (msgDate.before(nowDate)) {

            boolean sameDay = now_calendar.get(Calendar.YEAR) == msg_calendar.get(Calendar.YEAR) &&
                    now_calendar.get(Calendar.MONTH) == msg_calendar.get(Calendar.MONTH)
                    && now_calendar.get(Calendar.DAY_OF_MONTH) == msg_calendar.get(Calendar.DAY_OF_MONTH);
            Log.e("YESTERDAY", (now.get(Calendar.DATE) - msg_calendar.get(Calendar.DATE) == 1) + "");
            if (sameDay) {
                timeText.setVisibility(View.GONE);
                dividerTop.setVisibility(View.GONE);
                timeText.setText("");
            } else {
                timeText.setVisibility(View.VISIBLE);
                dividerTop.setVisibility(View.VISIBLE);
                if (DateUtils.isToday(now_calendar.getTimeInMillis())) {
                    timeText.setText("Today");
                } else if (now.get(Calendar.DATE) - now_calendar.get(Calendar.DATE) == 1) {
                    timeText.setText("Yesterday");
                } else {
                    timeText.setText("" + new SimpleDateFormat("dd MMM, yyyy").format(new Date(now_tm)));
                }
            }
        } else {
            timeText.setVisibility(View.GONE);
            dividerTop.setVisibility(View.GONE);
            timeText.setText("");
        }
    }


}

【讨论】：

【解决方案2】：

尝试将您的日期转换为Millis，然后使用这些<,>,<=,>=,==,!= 运算符进行比较或检查此link

.after 用于比较日期

【讨论】：

是的，这是一个很好的方法我还使用.before函数改进了我的代码sn-p。