TeamProject/other/07_210340176 张嘉欣_代码标注/ui/DateTimePickerDialog.java

/*
 * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.micode.notes.ui;

import java.util.Calendar;

import net.micode.notes.R;
import net.micode.notes.ui.DateTimePicker;
import net.micode.notes.ui.DateTimePicker.OnDateTimeChangedListener;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.text.format.DateFormat;
import android.text.format.DateUtils;

public class DateTimePickerDialog extends AlertDialog implements OnClickListener {

    private Calendar mDate = Calendar.getInstance();// 当前日期和时间
    private boolean mIs24HourView;// 是否为24小时制
    private OnDateTimeSetListener mOnDateTimeSetListener;// 日期时间设置监听器
    private DateTimePicker mDateTimePicker;// 日期时间选择器

    public interface OnDateTimeSetListener {
        void OnDateTimeSet(AlertDialog dialog, long date);
    }
    /**
     * 日期时间设置监听器
     */

    public DateTimePickerDialog(Context context, long date) {
        super(context);
        mDateTimePicker = new DateTimePicker(context);
        setView(mDateTimePicker);
        mDateTimePicker.setOnDateTimeChangedListener(new OnDateTimeChangedListener() {
            public void onDateTimeChanged(DateTimePicker view, int year, int month,
                    int dayOfMonth, int hourOfDay, int minute) {
                mDate.set(Calendar.YEAR, year);
                mDate.set(Calendar.MONTH, month);
                mDate.set(Calendar.DAY_OF_MONTH, dayOfMonth);
                mDate.set(Calendar.HOUR_OF_DAY, hourOfDay);
                mDate.set(Calendar.MINUTE, minute); // 将 mDate 对象设置为新的日期和时间
                updateTitle(mDate.getTimeInMillis());  //更新选择器的标题
            }
        });// 为 mDateTimePicker 设置一个匿名内部类作为日期时间变化监听器

        mDate.setTimeInMillis(date);
        mDate.set(Calendar.SECOND, 0);
        // 将传入的时间戳设置为 mDate 对象的时间，并将秒数设置为零

        mDateTimePicker.setCurrentDate(mDate.getTimeInMillis());  // 将当前日期和时间设置为日期时间选择器的默认值

        setButton(context.getString(R.string.datetime_dialog_ok), this);
        setButton2(context.getString(R.string.datetime_dialog_cancel), (OnClickListener)null); // 设置确定和取消按钮的文本

        set24HourView(DateFormat.is24HourFormat(this.getContext()));  // 根据系统的时间格式确定日期时间选择器是否为 24 小时制
        updateTitle(mDate.getTimeInMillis());// 更新选择器的标题
    }

    public void set24HourView(boolean is24HourView) {
        mIs24HourView = is24HourView;
    }
    //设置日期时间选择器是否显示为24小时制

    public void setOnDateTimeSetListener(OnDateTimeSetListener callBack) {
        mOnDateTimeSetListener = callBack;
    }
    //设置日期时间设置监听器

    private void updateTitle(long date) {
        int flag =
            DateUtils.FORMAT_SHOW_YEAR |
            DateUtils.FORMAT_SHOW_DATE |
            DateUtils.FORMAT_SHOW_TIME;
        // 定义日期、时间和小时制格式的标志

        flag |= mIs24HourView ? DateUtils.FORMAT_24HOUR : DateUtils.FORMAT_24HOUR;
        setTitle(DateUtils.formatDateTime(this.getContext(), date, flag));
        // 格式化时间戳为指定的日期、时间和小时制格式的字符串，并设置为选择器的标题
    }
    //更新选择器的标题

    public void onClick(DialogInterface arg0, int arg1) {
        // 如果日期时间设置监听器不为 null，则调用 OnDateTimeSet 方法并传递当前日期时间和对话框对象
        if (mOnDateTimeSetListener != null) {
            mOnDateTimeSetListener.OnDateTimeSet(this, mDate.getTimeInMillis());
        }
    }//当单击对话框的按钮时被调用

}