下面的代码显示了DatePickerDialog,供用户插入日期并按预期工作.当日期更新并且用户关闭对话框时,启动DatePickerDialog的按钮将更新以显示所选日期：

// Date Picker Section
@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
    case DATE_DIALOG_ID:
        Log.i(TAG, "Setting up new date picker "+timestampCalendar);
        datepicker =  new DatePickerDialog(this,
                mDateSetListener,
                timestampCalendar.get(Calendar.YEAR),
                timestampCalendar.get(Calendar.MONTH),
                timestampCalendar.get(Calendar.DATE));          
        return datepicker;
    }
    return null;
}

// updates the date we display in the Button
private void updateDateButton() {       
    timestampTextView.setText(monthName[timestampCalendar.get(Calendar.MONTH)]+", "+timestampCalendar.get(Calendar.DATE)+" "+timestampCalendar.get(Calendar.YEAR));
}

// the callback received when the user "sets" the date in the dialog
private DatePickerDialog.OnDateSetListener mDateSetListener =
    new DatePickerDialog.OnDateSetListener() {
    public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
        timestampCalendar.set(year, monthOfYear, dayOfMonth);
        datepicker.updateDate(timestampCalendar.get(Calendar.DATE), timestampCalendar.get(Calendar.MONTH), timestampCalendar.get(Calendar.DATE));
        updateDateButton();         
    }
};

但是这里是我开始遇到问题的地方.下面的代码是一个按钮的onClickListener,该按钮将一天添加到timestampCalendar Calendar对象.如果我打开DatePickerDialog并关闭它,请使用“ plus1”按钮,然后再次打开DatePickerDialog,它仍然显示我第一次关闭DatePickerDialog时的日期.

plus1.setOnClickListener(new View.OnClickListener() {           
        public void onClick(View view) {    
            timestampCalendar.add(Calendar.DATE, 1);
            currentTimestamp = timestampCalendar.getTimeInMillis();
            updateDateButton();
        }            
    });

我试图通过在设置侦听器中调用DatePickerDialog的updateDate()方法来解决此问题,但这也不起作用.

有人有想法么？

解决方法:

您需要致电此行：

datepicker.updateDate(timestampCalendar.get(Calendar.DATE), timestampCalendar.get(Calendar.MONTH), timestampCalendar.get(Calendar.DATE));

使用plus1按钮时.这将更新日期选择器.

您实际上可以将这行代码移到updateDateButton();中.停止重复.