Calendar ca = Calendar.getInstance();
mYear = ca.get(Calendar.YEAR);
mMonth = ca.get(Calendar.MONTH);
mDay = ca.get(Calendar.DAY_OF_MONTH);

btn_day.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View v) {
    //TODO 調(diào)用時間選擇器
    new DatePickerDialog(MainActivity.this, onDateSetListener, mYear, mMonth, mDay).show();
  }
});

/**
 * 日期選擇器對話框監(jiān)聽
 */
private DatePickerDialog.OnDateSetListener onDateSetListener = new DatePickerDialog.OnDateSetListener() {

  @Override
  public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
    mYear = year;
    mMonth = monthOfYear;
    mDay = dayOfMonth;
    String days;
    if (mMonth + 1 < 10) {
      if (mDay < 10) {
        days = new StringBuffer().append(mYear).append("年").append("0").
            append(mMonth + 1).append("月").append("0").append(mDay).append("日").toString();
      } else {
        days = new StringBuffer().append(mYear).append("年").append("0").
            append(mMonth + 1).append("月").append(mDay).append("日").toString();
      }

    } else {
      if (mDay < 10) {
        days = new StringBuffer().append(mYear).append("年").
            append(mMonth + 1).append("月").append("0").append(mDay).append("日").toString();
      } else {
        days = new StringBuffer().append(mYear).append("年").
            append(mMonth + 1).append("月").append(mDay).append("日").toString();
      }

    }
    tv_data.setText(days);
  }
};