Dome/src1/net/micode/notes/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 {

    // 定义一个Calendar对象，用于存储日期和时间
    private Calendar mDate = Calendar.getInstance();
    // 定义一个布尔变量，用于判断是否为24小时制
    private boolean mIs24HourView;
    // 定义一个OnDateTimeSetListener对象，用于监听日期时间的设置
    private OnDateTimeSetListener mOnDateTimeSetListener;
    // 定义一个DateTimePicker对象，用于显示日期时间选择器
    private DateTimePicker mDateTimePicker;

 // 定义一个接口，用于监听日期时间设置
    public interface OnDateTimeSetListener {
        // 当日期时间设置时，调用此方法
        void OnDateTimeSet(AlertDialog dialog, long date);
    }

// 定义一个DateTimePickerDialog类，传入Context和long类型的date参数
    public DateTimePickerDialog(Context context, long date) {
        // 调用父类的构造方法
        super(context);
        // 创建一个DateTimePicker对象
        mDateTimePicker = new DateTimePicker(context);
        // 设置视图
        setView(mDateTimePicker);
        // 设置DateTimePicker的监听器
        mDateTimePicker.setOnDateTimeChangedListener(new OnDateTimeChangedListener() {
            public void onDateTimeChanged(DateTimePicker view, int year, int month,
                    int dayOfMonth, int hourOfDay, int minute) {
                // 设置日期
                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);
                // 更新标题
                updateTitle(mDate.getTimeInMillis());
            }
        });
        // 设置日期
        mDate.setTimeInMillis(date);
        mDate.set(Calendar.SECOND, 0);
        // 设置当前日期
        mDateTimePicker.setCurrentDate(mDate.getTimeInMillis());
        // 设置按钮
        setButton(context.getString(R.string.datetime_dialog_ok), this);
        setButton2(context.getString(R.string.datetime_dialog_cancel), (OnClickListener)null);
        // 设置24小时制
        set24HourView(DateFormat.is24HourFormat(this.getContext()));
        // 更新标题
        updateTitle(mDate.getTimeInMillis());
    }

  // 设置是否为24小时制
    public void set24HourView(boolean is24HourView) {
        mIs24HourView = is24HourView;
    }

// 设置日期时间设置监听器
    public void setOnDateTimeSetListener(OnDateTimeSetListener callBack) {
        // 将传入的监听器赋值给成员变量
        mOnDateTimeSetListener = callBack;
    }

   // 更新标题
    private void updateTitle(long date) {
        // 设置日期格式
        int flag =
            DateUtils.FORMAT_SHOW_YEAR |
            DateUtils.FORMAT_SHOW_DATE |
            DateUtils.FORMAT_SHOW_TIME;
        // 如果是24小时制，则设置格式为24小时制
        flag |= mIs24HourView ? DateUtils.FORMAT_24HOUR : DateUtils.FORMAT_24HOUR;
        // 格式化日期并设置标题
        setTitle(DateUtils.formatDateTime(this.getContext(), date, flag));
    }

    public void onClick(DialogInterface arg0, int arg1) {
        // 如果mOnDateTimeSetListener不为空，则调用其OnDateTimeSet方法，传入当前对象和mDate的时间戳
        if (mOnDateTimeSetListener != null) {
            mOnDateTimeSetListener.OnDateTimeSet(this, mDate.getTimeInMillis());
        }
    }

}