5 changed files with 65 additions and 37 deletions
--- a/Notes-master/.idea/.gitignore
+++ b/Notes-master/.idea/.gitignore
@ -0,0 +1,3 @@
+# Default ignored files
+/shelf/
+/workspace.xml
--- a/Notes-master/.idea/misc.xml
+++ b/Notes-master/.idea/misc.xml
@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
--- a/Notes-master/.idea/modules.xml
+++ b/Notes-master/.idea/modules.xml
@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/Notes-master.iml" filepath="$PROJECT_DIR$/Notes-master.iml" />
+    </modules>
+  </component>
+</project>
--- a/Notes-master/Notes-master.iml
+++ b/Notes-master/Notes-master.iml
@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
--- a/Notes-master/src/net/micode/notes/data/NotesDatabaseHelper.java
+++ b/Notes-master/src/net/micode/notes/data/NotesDatabaseHelper.java
@ -30,19 +30,19 @@ import net.micode.notes.data.Notes.NoteColumns;
 public class NotesDatabaseHelper extends SQLiteOpenHelper {
    private static final String DB_NAME = "note.db";

-    private static final int DB_VERSION = 4;
+    private static final int DB_VERSION = 4;// 数据库版本号

    public interface TABLE {
-        public static final String NOTE = "note";
+        public static final String NOTE = "note";// 笔记表名

-        public static final String DATA = "data";
+        public static final String DATA = "data";// 数据表名
    }

    private static final String TAG = "NotesDatabaseHelper";

    private static NotesDatabaseHelper mInstance;

-    private static final String CREATE_NOTE_TABLE_SQL =
+    private static final String CREATE_NOTE_TABLE_SQL =// 创建笔记表的SQL语句
        "CREATE TABLE " + TABLE.NOTE + "(" +
            NoteColumns.ID + " INTEGER PRIMARY KEY," +
            NoteColumns.PARENT_ID + " INTEGER NOT NULL DEFAULT 0," +
@ -63,7 +63,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
            NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" +
        ")";

-    private static final String CREATE_DATA_TABLE_SQL =
+    private static final String CREATE_DATA_TABLE_SQL =// 创建数据表的SQL语句
        "CREATE TABLE " + TABLE.DATA + "(" +
            DataColumns.ID + " INTEGER PRIMARY KEY," +
            DataColumns.MIME_TYPE + " TEXT NOT NULL," +
@ -78,14 +78,14 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
            DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" +
        ")";

-    private static final String CREATE_DATA_NOTE_ID_INDEX_SQL =
+    private static final String CREATE_DATA_NOTE_ID_INDEX_SQL =// 创建数据表中NOTE_ID的索引SQL语句
        "CREATE INDEX IF NOT EXISTS note_id_index ON " +
        TABLE.DATA + "(" + DataColumns.NOTE_ID + ");";

    /**
     * Increase folder's note count when move note to the folder
     */
-    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =// 触发器：更新时增加文件夹笔记数量
        "CREATE TRIGGER increase_folder_count_on_update "+
        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
        " BEGIN " +
@ -97,7 +97,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
    /**
     * Decrease folder's note count when move note from folder
     */
-    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER = // 触发器：更新时减少文件夹笔记数量
        "CREATE TRIGGER decrease_folder_count_on_update " +
        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
        " BEGIN " +
@ -110,7 +110,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
    /**
     * Increase folder's note count when insert new note to the folder
     */
-    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER =
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER =// 触发器：删除时减少文件夹笔记数量
        "CREATE TRIGGER increase_folder_count_on_insert " +
        " AFTER INSERT ON " + TABLE.NOTE +
        " BEGIN " +
@ -133,7 +133,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        " END";

    /**
-     * Update note's content when insert data with type {@link DataConstants#NOTE}
+     * 当插入数据类型为 {@link DataConstants#NOTE} 时，更新笔记内容
     */
    private static final String DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER =
        "CREATE TRIGGER update_note_content_on_insert " +
@ -146,7 +146,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        " END";

    /**
-     * Update note's content when data with {@link DataConstants#NOTE} type has changed
+     * 当数据类型为 {@link DataConstants#NOTE} 的数据发生更改时，更新笔记内容
     */
    private static final String DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER =
        "CREATE TRIGGER update_note_content_on_update " +
@ -172,7 +172,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        " END";

    /**
-     * Delete datas belong to note which has been deleted
+     * 当数据表中的笔记被删除时，更新笔记内容触发器
     */
    private static final String NOTE_DELETE_DATA_ON_DELETE_TRIGGER =
        "CREATE TRIGGER delete_data_on_delete " +
@ -182,8 +182,9 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        "   WHERE " + DataColumns.NOTE_ID + "=old." + NoteColumns.ID + ";" +
        " END";

+
    /**
-     * Delete notes belong to folder which has been deleted
+     * 当文件夹被删除时，删除其中的笔记触发器
     */
    private static final String FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER =
        "CREATE TRIGGER folder_delete_notes_on_delete " +
@ -194,7 +195,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        " END";

    /**
-     * Move notes belong to folder which has been moved to trash folder
+     * 当文件夹中的笔记被移动到垃圾箱时，触发器将其移动到垃圾箱
     */
    private static final String FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER =
        "CREATE TRIGGER folder_move_notes_on_trash " +
@ -211,13 +212,13 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
    }

    public void createNoteTable(SQLiteDatabase db) {
-        db.execSQL(CREATE_NOTE_TABLE_SQL);
+        db.execSQL(CREATE_NOTE_TABLE_SQL); // 创建笔记表
        reCreateNoteTableTriggers(db);
        createSystemFolder(db);
        Log.d(TAG, "note table has been created");
    }

-    private void reCreateNoteTableTriggers(SQLiteDatabase db) {
+    private void reCreateNoteTableTriggers(SQLiteDatabase db) {// 重新创建笔记表触发器
        db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_update");
        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_update");
        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_delete");
@ -235,18 +236,17 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        db.execSQL(FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER);
    }

-    private void createSystemFolder(SQLiteDatabase db) {
+    private void createSystemFolder(SQLiteDatabase db) {  // 创建系统文件夹
        ContentValues values = new ContentValues();
-
-        /**
-         * call record foler for call notes
-         */
+/**
+ * 通话记录文件夹
+ */
        values.put(NoteColumns.ID, Notes.ID_CALL_RECORD_FOLDER);
        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
        db.insert(TABLE.NOTE, null, values);

        /**
-         * root folder which is default folder
+         * 默认根文件夹
         */
        values.clear();
        values.put(NoteColumns.ID, Notes.ID_ROOT_FOLDER);
@ -254,7 +254,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        db.insert(TABLE.NOTE, null, values);

        /**
-         * temporary folder which is used for moving note
+         * 临时文件夹，用于移动笔记
         */
        values.clear();
        values.put(NoteColumns.ID, Notes.ID_TEMPARAY_FOLDER);
@ -262,7 +262,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        db.insert(TABLE.NOTE, null, values);

        /**
-         * create trash folder
+         * 创建垃圾箱文件夹
         */
        values.clear();
        values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER);
@ -270,24 +270,24 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        db.insert(TABLE.NOTE, null, values);
    }

-    public void createDataTable(SQLiteDatabase db) {
+    public void createDataTable(SQLiteDatabase db) {  // 创建数据表
        db.execSQL(CREATE_DATA_TABLE_SQL);
        reCreateDataTableTriggers(db);
        db.execSQL(CREATE_DATA_NOTE_ID_INDEX_SQL);
        Log.d(TAG, "data table has been created");
    }

-    private void reCreateDataTableTriggers(SQLiteDatabase db) {
+    private void reCreateDataTableTriggers(SQLiteDatabase db) { // 删除旧的触发器
        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_insert");
        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_update");
        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_delete");
-
+        // 创建新的数据表触发器
        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER);
        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER);
        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_DELETE_TRIGGER);
    }

-    static synchronized NotesDatabaseHelper getInstance(Context context) {
+    static synchronized NotesDatabaseHelper getInstance(Context context) { // 获取单例实例
        if (mInstance == null) {
            mInstance = new NotesDatabaseHelper(context);
        }
@ -295,7 +295,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
    }

    @Override
-    public void onCreate(SQLiteDatabase db) {
+    public void onCreate(SQLiteDatabase db) { // 创建数据库时调用的方法，创建笔记表和数据表
        createNoteTable(db);
        createDataTable(db);
    }
@ -305,24 +305,24 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        boolean reCreateTriggers = false;
        boolean skipV2 = false;

-        if (oldVersion == 1) {
+        if (oldVersion == 1) {  // 升级到版本2
            upgradeToV2(db);
-            skipV2 = true; // this upgrade including the upgrade from v2 to v3
+            skipV2 = true; // 此次升级包括从版本2到版本3的升级
            oldVersion++;
        }

        if (oldVersion == 2 && !skipV2) {
-            upgradeToV3(db);
+            upgradeToV3(db);   // 升级到版本3
            reCreateTriggers = true;
            oldVersion++;
        }

-        if (oldVersion == 3) {
+        if (oldVersion == 3) { // 升级到版本4
            upgradeToV4(db);
            oldVersion++;
        }

-        if (reCreateTriggers) {
+        if (reCreateTriggers) { // 重新创建触发器
            reCreateNoteTableTriggers(db);
            reCreateDataTableTriggers(db);
        }
@ -333,14 +333,14 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        }
    }

-    private void upgradeToV2(SQLiteDatabase db) {
+    private void upgradeToV2(SQLiteDatabase db) { // 升级到版本2，重新创建笔记表和数据表
        db.execSQL("DROP TABLE IF EXISTS " + TABLE.NOTE);
        db.execSQL("DROP TABLE IF EXISTS " + TABLE.DATA);
        createNoteTable(db);
        createDataTable(db);
    }

-    private void upgradeToV3(SQLiteDatabase db) {
+    private void upgradeToV3(SQLiteDatabase db) { // 升级到版本3，添加新列和系统文件夹
        // drop unused triggers
        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_insert");
        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_delete");
@ -355,7 +355,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
        db.insert(TABLE.NOTE, null, values);
    }

-    private void upgradeToV4(SQLiteDatabase db) {
+    private void upgradeToV4(SQLiteDatabase db) { // 升级到版本4，添加新列
        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.VERSION
                + " INTEGER NOT NULL DEFAULT 0");
    }