对AlarmInitReceiver.java进行阅读理解以及添加注解

Signed-off-by: qianji <1535486312@qq.com>

Notes-master1/.idea/modules.xml

@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/.idea/Notes-master1.iml" filepath="$PROJECT_DIR$/.idea/Notes-master1.iml" />
-    </modules>
-  </component>
-</project>

Notes-master1/.idea/sonarlint/issuestore/index.pb

@@ -6,4 +6,18 @@
 X
 (gradle/wrapper/gradle-wrapper.properties,f\b\fbe448ebfc3eb2d4e308f6b8b043666f5b57235e
 k
-;app/src/main/java/net/micode/notes/ui/NotesListAdapter.java,2\8\283f16cc23da56ca65616082bc810304d3511d0a
+;app/src/main/java/net/micode/notes/ui/NotesListAdapter.java,2\8\283f16cc23da56ca65616082bc810304d3511d0a
+f
+6app/src/main/java/net/micode/notes/tool/DataUtils.java,3\2\32360bf24febc78f20db52498c7576b3d8650d56
+@
+app/build.gradle,f\4\f4a01d6a4fcb971362ec00a83903fd3902f52164
+m
+=app/src/main/java/net/micode/notes/ui/AlarmAlertActivity.java,3\e\3e688be40dc69cfd1062f41d0fc27fe261a26710
+i
+9app/src/main/java/net/micode/notes/ui/DateTimePicker.java,6\c\6cbf8bd9aa98eff862b1dc067330ba66ba4493aa
+h
+8app/src/main/java/net/micode/notes/ui/AlarmReceiver.java,5\8\5836a695995df8fadacfa6409fe8d21d88946842
+b
+2app/src/main/java/net/micode/notes/data/Notes.java,a\7\a7641cfac724321d508c2a284223a711011a93f5
+l
+<app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java,0\2\0268ec648e2fc0139b30ed13396174b7392c1ae2

Notes-master1/.idea/sonarlint/securityhotspotstore/index.pb

@@ -6,4 +6,18 @@
 X
 (gradle/wrapper/gradle-wrapper.properties,f\b\fbe448ebfc3eb2d4e308f6b8b043666f5b57235e
 k
-;app/src/main/java/net/micode/notes/ui/NotesListAdapter.java,2\8\283f16cc23da56ca65616082bc810304d3511d0a
+;app/src/main/java/net/micode/notes/ui/NotesListAdapter.java,2\8\283f16cc23da56ca65616082bc810304d3511d0a
+f
+6app/src/main/java/net/micode/notes/tool/DataUtils.java,3\2\32360bf24febc78f20db52498c7576b3d8650d56
+@
+app/build.gradle,f\4\f4a01d6a4fcb971362ec00a83903fd3902f52164
+m
+=app/src/main/java/net/micode/notes/ui/AlarmAlertActivity.java,3\e\3e688be40dc69cfd1062f41d0fc27fe261a26710
+h
+8app/src/main/java/net/micode/notes/ui/AlarmReceiver.java,5\8\5836a695995df8fadacfa6409fe8d21d88946842
+i
+9app/src/main/java/net/micode/notes/ui/DateTimePicker.java,6\c\6cbf8bd9aa98eff862b1dc067330ba66ba4493aa
+b
+2app/src/main/java/net/micode/notes/data/Notes.java,a\7\a7641cfac724321d508c2a284223a711011a93f5
+l
+<app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java,0\2\0268ec648e2fc0139b30ed13396174b7392c1ae2

Notes-master1/.idea/vcs.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
-  </component>
-</project>

Notes-master1/app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java

@@ -35,18 +35,23 @@ public class AlarmInitReceiver extends BroadcastReceiver {
         NoteColumns.ALERTED_DATE
     };
 
+    //对数据库的操作，调用标签ID和闹钟时间
     private static final int COLUMN_ID                = 0;
     private static final int COLUMN_ALERTED_DATE      = 1;
 
     @Override
     public void onReceive(Context context, Intent intent) {
         long currentDate = System.currentTimeMillis();
+        //System.currentTimeMillis()产生一个当前的毫秒
+        //这个毫秒其实就是自1970年1月1日0时起的毫秒数
         Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI,
                 PROJECTION,
                 NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE,
                 new String[] { String.valueOf(currentDate) },
+                //将long变量currentDate转化为字符串
                 null);
-
+                //要访问内容提供器中共享的数据，就需要借助ContentResolver类，通过Context中的getContentResolver方法获取该类的实例。
+                //这个类提供了insert\update\delete\query用于添加、更新、删除和查询数据。和SQLiteDatabase那块比较相似，但也有不同。
         if (c != null) {
             if (c.moveToFirst()) {
                 do {
@@ -59,7 +64,11 @@ public class AlarmInitReceiver extends BroadcastReceiver {
                     alermManager.set(AlarmManager.RTC_WAKEUP, alertDate, pendingIntent);
                 } while (c.moveToNext());
             }
+            //Cursor(光标)的遍历
             c.close();
         }
+        //然而通过网上查找资料发现，对于闹钟机制的启动，通常需要上面的几个步骤
+        //如新建Intent、PendingIntent以及AlarmManager等
+        //这里就是根据数据库里的闹钟时间创建一个闹钟机制
     }
 }