[注释]

.idea/vcs.xml

@@ -2,5 +2,6 @@
 <project version="4">
   <component name="VcsDirectoryMappings">
     <mapping directory="" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
   </component>
 </project>

app/src/main/java/net/micode/notes/ui/AlarmAlertActivity.java

@@ -40,69 +40,71 @@ import net.micode.notes.tool.DataUtils;
 import java.io.IOException;
 
 
-public class AlarmAlertActivity extends Activity implements OnClickListener, OnDismissListener {
-    private long mNoteId;
-    private String mSnippet;
-    private static final int SNIPPET_PREW_MAX_LEN = 60;
-    MediaPlayer mPlayer;
-
-    @Override
-    protected void onCreate(Bundle savedInstanceState) {
+@Override
+protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         requestWindowFeature(Window.FEATURE_NO_TITLE);
 
-        final Window win = getWindow();
+final Window win = getWindow();
         win.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
 
         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);
+        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);
         }
 
         Intent intent = getIntent();
 
         try {
-            mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
-            mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
-            mSnippet = mSnippet.length() > SNIPPET_PREW_MAX_LEN ? mSnippet.substring(0,
-                    SNIPPET_PREW_MAX_LEN) + getResources().getString(R.string.notelist_string_info)
-                    : mSnippet;
+        // 获取传递过来的NoteId和Snippet
+        mNoteId = Long.valueOf(intent.getData().getPathSegments().get(1));
+        mSnippet = DataUtils.getSnippetById(this.getContentResolver(), mNoteId);
+        // 处理提醒信息的文本长度和显示方式
+        mSnippet = mSnippet.length() > SNIPPET_PREW_MAX_LEN ? mSnippet.substring(0,
+        SNIPPET_PREW_MAX_LEN) + getResources().getString(R.string.notelist_string_info)
+        : mSnippet;// 如果文本过长则截取前60个字符，加上一个显示“…”的标识
         } catch (IllegalArgumentException e) {
-            e.printStackTrace();
-            return;
+        e.printStackTrace();
+        return;
         }
 
         mPlayer = new MediaPlayer();
+        // 从数据源中查询记录是否存在，如果存在则显示提醒菜单和播放提醒声音，否则结束Activity
         if (DataUtils.visibleInNoteDatabase(getContentResolver(), mNoteId, Notes.TYPE_NOTE)) {
-            showActionDialog();
-            playAlarmSound();
+        showActionDialog();// 显示提醒菜单
+        playAlarmSound();// 播放提醒声音
         } else {
-            finish();
+        finish();// Note不存在，结束Activity
+        }
         }
-    }
 
-    private boolean isScreenOn() {
-        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
-        return pm.isScreenOn();
-    }
+private boolean isScreenOn() {// 检测屏幕是否点亮
+        PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);// 获取PowerManager对象
+        return pm.isScreenOn(); // 返回屏幕是否点亮的状态
+        }
 
     private void playAlarmSound() {
+        // 获取系统设置中的闹钟铃声
         Uri url = RingtoneManager.getActualDefaultRingtoneUri(this, RingtoneManager.TYPE_ALARM);
-
+        // 获取当前系统模式下是否与闹钟声音相应
         int silentModeStreams = Settings.System.getInt(getContentResolver(),
                 Settings.System.MODE_RINGER_STREAMS_AFFECTED, 0);
-
+        // 设置播放器的音频串流类型
         if ((silentModeStreams & (1 << AudioManager.STREAM_ALARM)) != 0) {
             mPlayer.setAudioStreamType(silentModeStreams);
         } else {
             mPlayer.setAudioStreamType(AudioManager.STREAM_ALARM);
         }
         try {
+        // 设置播放器的数据源
             mPlayer.setDataSource(this, url);
+        // 缓冲播放器的媒体源数据
             mPlayer.prepare();
+        // 设置播放器循环播放
             mPlayer.setLooping(true);
+        // 播放闹钟声音
             mPlayer.start();
         } catch (IllegalArgumentException e) {
             // TODO Auto-generated catch block