xiaomi-note/week-01/ui/AlarmAlertActivity.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 android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.content.DialogInterface.OnDismissListener;
import android.content.Intent;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.RingtoneManager;
import android.net.Uri;
import android.os.Bundle;
import android.os.PowerManager;
import android.provider.Settings;
import android.support.v7.app.AppCompatActivity;
import android.view.Window;
import android.view.WindowManager;

import net.micode.notes.R;
import net.micode.notes.data.Notes;
import net.micode.notes.tool.DataUtils;

import java.io.IOException;

//闹钟提醒
//OnDismissListener 接口是对话消失监听器
public class AlarmAlertActivity extends AppCompatActivity implements OnClickListener, OnDismissListener {
    private long mNoteId;
    private String mSnippet;
    private static final int SNIPPET_PREW_MAX_LEN = 60;
    MediaPlayer mPlayer;
    //OnCreate是Android中的一个特别的函数，用来"表示一个窗口正在生成"。其不产生窗口，只是在窗口显示前设置窗口的属性如风格、位置颜色等。
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);//去掉标题栏
//息屏显示
        final Window win = getWindow();
        win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
//如果非亮屏，执行点亮屏幕操作：保持屏幕亮；唤醒屏幕；当屏幕亮时，允许锁屏。
        if (!isScreenOn()) {
            win.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON//屏幕亮度控制
                    | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
                    | WindowManager.LayoutParams.FLAG_ALLOW_LOCK_WHILE_SCREEN_ON
                    | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR);
        }
        //获得Intent用于开启Activity
        Intent intent = getIntent();
//try-catch异常处理
        try {
            //获取便签的id
            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
            //通过该id获取所对应便签的摘要
            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
            //判断mSnippet长度，过长则将其削减到合适长度
            mSnippet = mSnippet.length() > SNIPPET_PREW_MAX_LEN ? mSnippet.substring(0,
                    SNIPPET_PREW_MAX_LEN) + getResources().getString(R.string.notelist_string_info)
                    : mSnippet;
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
            return;
        }
//实例化mplayer,新建一个媒体播放器
        mPlayer = new MediaPlayer();
        //通过id从数据库中获取其类型，判断是否需要提醒
        if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
            showActionDialog();
            playAlarmSound();
        } else {
            finish();
        }
    }

    private boolean isScreenOn() {
        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
        return pm.isScreenOn();
    }

    private void playAlarmSound() {
        Uri url = RingtoneManager.getActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM);

        int silentModeStreams = Settings.System.getInt(getContentResolver(),
                Settings.System.MODE_RINGER_STREAMS_AFFECTED, 0);
//获取手机状态
        //判断是否静音
        if ((silentModeStreams & (1 << AudioManager.STREAM_ALARM)) != 0) {//用于警报的音频流
            mPlayer.setAudioStreamType(silentModeStreams);//指定媒体流的类型
        } else {
            mPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
        }
        try {
            mPlayer.setDataSource(this, url);
            mPlayer.prepare();//准备播放
            mPlayer.setLooping(true);//控制是否循环播放
            mPlayer.start();//开始播放
        } catch (IllegalArgumentException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SecurityException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IllegalStateException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    //界面设计
//新建对话框，设置标题，设置内容，设置ok按钮，设置enter按钮
    private void showActionDialog() {
        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
        dialog.setTitle(R.string.app_name);
        dialog.setMessage(mSnippet);//文本内容
        dialog.setPositiveButton(R.string.notealert_ok, this);
        if (isScreenOn()) {//选择确定界面反应
            dialog.setNegativeButton(R.string.notealert_enter, this);
        }
        dialog.show().setOnDismissListener(this);//选择不确定界面
    }
    //实现监听器OnClickListener具体功能实现
//dialog对话框，negative一般用于取消
//onClick方法，处理点击事件
    public void onClick(DialogInterface dialog, int which) {
        switch (which) {//获取输入框中内容
            //取消按钮
            case DialogInterface.BUTTON_NEGATIVE:
                //新建Intent，指向NoteEditActivity；设置VIEW动作：显示用户数据；附加上便签的id；启动
                Intent intent = new Intent(this, NoteEditActivity.class);////启动小组件或者是绑定关系，这里是绑定关系，参数分别为上下文要跳转的Activity类
                intent.setAction(Intent.ACTION_VIEW);//自动以最合适的方式显示Data（执行动作类别）
                intent.putExtra(Intent.EXTRA_UID, mNoteId);//扩展信息，要传递的值赋值到intent
                startActivity(intent);//启动intent实现跳转
                break;
            default:
                break;
        }
    }

    public void onDismiss(DialogInterface dialog) {
        stopAlarmSound();//停止报警声音
        finish();//结束运行
    }
    //停止闹钟声音
    private void stopAlarmSound() {
        if (mPlayer != null) {
            mPlayer.stop();
            mPlayer.release();
            mPlayer = null;
        }
    }
}