xiaomi/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.
 */
// 定义包名和导入所需的类
package net.micode.notes.ui;

// 导入Android框架中用于对话框、音频、媒体播放等相关功能的类
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.view.Window;
import android.view.WindowManager;

// 导入应用程序自己的资源和工具类
import net.micode.notes.R;
import net.micode.notes.data.Notes;
import net.micode.notes.tool.DataUtils;

// 导入Java的IO功能，用于处理可能的输入输出异常
import java.io.IOException;

// 定义AlarmAlertActivity类，它是一个Activity，用于显示闹钟提醒
public class AlarmAlertActivity extends Activity implements OnClickListener, OnDismissListener {
    // 定义成员变量，用于存储笔记的ID和预览文本
    private long mNoteId;
    private String mSnippet;
    // 定义一个常量，用于限制预览文本的最大长度
    private static final int SNIPPET_PREW_MAX_LEN = 60;
    // 定义MediaPlayer对象，用于播放闹钟声音
    MediaPlayer mPlayer;

    // onCreate方法，当Activity创建时被调用
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // 请求无标题的窗口特性
        requestWindowFeature(Window.FEATURE_NO_TITLE);

        // 获取当前窗口，并添加标记以确保即使在锁屏时也能显示
        final Window win = getWindow();
        win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);

        // 检查屏幕是否已经开启，如果没有，则添加标记以保持屏幕开启
        if (!isScreenOn()) {
            win.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
                    | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
                    | WindowManager.LayoutParams.FLAG_ALLOW_LOCK_WHILE_SCREEN_ON
                    | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR);
        }

        // 获取启动Activity的Intent
        Intent intent = getIntent();

        try {
            // 从Intent中获取笔记ID
            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
            // 根据笔记ID获取笔记的预览文本
            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
            // 如果预览文本超过最大长度，则截断并添加省略号
            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;
        }

        // 创建MediaPlayer对象
        mPlayer = new MediaPlayer();
        // 如果笔记存在于数据库中，则显示操作对话框并播放闹钟声音
        if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
            showActionDialog();
            playAlarmSound();
        } else {
            // 如果笔记不存在，则结束Activity
            finish();
        }
    }

    // 检查屏幕是否开启
    private boolean isScreenOn() {
        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
        return pm.isScreenOn();
    }

    // 播放闹钟声音
    private void playAlarmSound() {
        // 获取默认闹钟铃声的Uri
        Uri url = RingtoneManager.getActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM);

        // 获取受影响的音频流类型
        int silentModeStreams = Settings.System.getInt(getContentResolver(),
                Settings.System.MODE_RINGER_STREAMS_AFFECTED, 0);

        // 如果闹钟铃声被静音模式影响，则设置MediaPlayer的音频流类型
        if ((silentModeStreams & (1 << AudioManager.STREAM_ALARM)) != 0) {
            mPlayer.setAudioStreamType(silentModeStreams);
        } else {
            mPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
        }
        try {
            // 设置MediaPlayer的数据源为闹钟铃声，并准备播放
            mPlayer.setDataSource(this, url);
            mPlayer.prepare();
            mPlayer.setLooping(true);
            mPlayer.start();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 显示操作对话框
    private void showActionDialog() {
        // 创建AlertDialog.Builder对象
        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
        // 设置对话框标题和消息
        dialog.setTitle(R.string.app_name);
        dialog.setMessage(mSnippet);
        // 设置对话框的肯定按钮，并添加点击事件监听器
        dialog.setPositiveButton(R.string.notealert_ok, this);
        // 如果屏幕已经开启，则设置对话框的否定按钮
        if (isScreenOn()) {
            dialog.setNegativeButton(R.string.notealert_enter, this);
        }
        // 显示对话框，并添加消失事件监听器
        dialog.show().setOnDismissListener(this);
    }

    // 点击事件处理方法
    public void onClick(DialogInterface dialog, int which) {
        switch (which) {
            case DialogInterface.BUTTON_NEGATIVE:
                // 如果用户点击否定按钮，则启动NoteEditActivity
                Intent intent = new Intent(this, NoteEditActivity.class);
                intent.setAction(Intent.ACTION_VIEW);
                intent.putExtra(Intent.EXTRA_UID, mNoteId);
                startActivity(intent);
                break;
            default:
                // 默认不做任何操作
                break;
        }
    }

    // 对话框消失事件处理方法
    public void onDismiss(DialogInterface dialog) {
        // 停止闹钟声音，并结束Activity
        stopAlarmSound();
        finish();
    }

    // 停止闹钟声音
    private void stopAlarmSound() {
        // 如果MediaPlayer对象不为空，则停止播放并释放资源
        if (mPlayer != null) {
            mPlayer.stop();
            mPlayer.release();
            mPlayer = null;
        }
    }
}