123/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.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;

// 定义一个名为 AlarmAlertActivity 的 Activity
public class AlarmAlertActivity extends Activity implements OnClickListener, OnDismissListener {
// 用于存储笔记的 ID
    private long mNoteId;
    private String mSnippet;
// 定义片段预览的最大长度
    private static final int SNIPPET_PREW_MAX_LEN = 60;
// 定义媒体播放器，用于播放闹钟声音
    MediaPlayer mPlayer;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
	// 获取窗口对象
        final Window win = getWindow();
// 设置在锁屏状态下也能显示该窗口
        win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
	// 如果屏幕没有点亮
        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);
        }
	// 获取启动该 Activity 的 Intent
        Intent intent = getIntent();

        try {
	// 从 Intent 的数据中获取路径片段中的第二个元素作为笔记 ID
            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
// 根据笔记 ID 获取笔记片段
            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
// 如果片段长度超过最大长度，则截断并添加提示信息
            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;
        }
	// 创建媒体播放器对象
        mPlayer = new MediaPlayer();
        if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
            showActionDialog();
            playAlarmSound();
        } else {
            finish();
        }
    }
	// 判断屏幕是否点亮
    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);
	// 获取系统设置中铃声流的静音模式状态
        int silentModeStreams = Settings.System.getInt(getContentResolver(),
                Settings.System.MODE_RINGER_STREAMS_AFFECTED, 0);

        if ((silentModeStreams & (1 << AudioManager.STREAM_ALARM)) != 0) {
            mPlayer.setAudioStreamType(silentModeStreams);
        } else {
            mPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
        }
        try {
// 设置媒体播放器的数据源为闹钟铃声的 Uri
            mPlayer.setDataSource(this, url);
            mPlayer.prepare();
            mPlayer.setLooping(true);
/ 开始播放
            mPlayer.start();
        } 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();
        }
    }
 // 显示操作对话框
    private void showActionDialog() {
        AlertDialog.Builder dialog = new AlertDialog.Builder(this);
        dialog.setTitle(R.string.app_name);
        dialog.setMessage(mSnippet);

        dialog.setPositiveButton(R.string.notealert_ok, this);
        if (isScreenOn()) {
            dialog.setNegativeButton(R.string.notealert_enter, this);
        }
        dialog.show().setOnDismissListener(this);
    }
 // 对话框关闭事件处理方法
    public void onClick(DialogInterface dialog, int which) {
        switch (which) {s
            case DialogInterface.BUTTON_NEGATIVE:
                Intent intent = new Intent(this, NoteEditActivity.class);
                intent.setAction(Intent.ACTION_VIEW);
                intent.putExtra(Intent.EXTRA_UID, mNoteId);
                startActivity(intent);
                break;
            default:
                break;
        }
    }
// 对话框关闭事件处理方法
    public void onDismiss(DialogInterface dialog) {
        stopAlarmSound();
        finish();
    }
 // 停止闹钟声音的方法
    private void stopAlarmSound() {
        if (mPlayer != null) {
            mPlayer.stop();
            mPlayer.release();
            mPlayer = null;
        }
    }
}