diff --git a/src/net/micode/notes/data/Contact.java b/src/net/micode/notes/data/Contact.java index d97ac5d..a2147ec 100644 --- a/src/net/micode/notes/data/Contact.java +++ b/src/net/micode/notes/data/Contact.java @@ -25,10 +25,11 @@ import android.util.Log; import java.util.HashMap; -public class Contact { +public class Contact { //联系人 private static HashMap sContactCache; private static final String TAG = "Contact"; + // 定义字符串CALLER_ID_SELECTION private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'" + " AND " + Data.RAW_CONTACT_ID + " IN " @@ -36,17 +37,20 @@ public class Contact { + " FROM phone_lookup" + " WHERE min_match = '+')"; + // 获取联系人 public static String getContact(Context context, String phoneNumber) { if(sContactCache == null) { sContactCache = new HashMap(); } + // 查找HashMap中是否已有phoneNumber信息 if(sContactCache.containsKey(phoneNumber)) { return sContactCache.get(phoneNumber); } String selection = CALLER_ID_SELECTION.replace("+", PhoneNumberUtils.toCallerIDMinMatch(phoneNumber)); + // 查找数据库中phoneNumber的信息 Cursor cursor = context.getContentResolver().query( Data.CONTENT_URI, new String [] { Phone.DISPLAY_NAME }, @@ -54,16 +58,21 @@ public class Contact { new String[] { phoneNumber }, null); + // 判定查询结果 + // moveToFirst()返回第一条 if (cursor != null && cursor.moveToFirst()) { try { + // 找到相关信息 String name = cursor.getString(0); sContactCache.put(phoneNumber, name); return name; + // 异常 } catch (IndexOutOfBoundsException e) { Log.e(TAG, " Cursor get string error " + e.toString()); return null; } finally { cursor.close(); + // 未找到相关信息 } } else { Log.d(TAG, "No contact matched with number:" + phoneNumber); diff --git a/src/net/micode/notes/data/Notes.java b/src/net/micode/notes/data/Notes.java index f240604..0bb8b30 100644 --- a/src/net/micode/notes/data/Notes.java +++ b/src/net/micode/notes/data/Notes.java @@ -17,9 +17,11 @@ package net.micode.notes.data; import android.net.Uri; +// Notes 类中定义了很多常量，这些常量大多是int型和string型 public class Notes { public static final String AUTHORITY = "micode_notes"; public static final String TAG = "Notes"; + //以下三个常量对NoteColumns.TYPE的值进行设置时会用到 public static final int TYPE_NOTE = 0; public static final int TYPE_FOLDER = 1; public static final int TYPE_SYSTEM = 2; @@ -54,13 +56,14 @@ public class Notes { /** * Uri to query all notes and folders */ - public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note"); + public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");//定义查询便签和文件夹的指针。 /** * Uri to query data */ - public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data"); + public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");//定义查找数据的指针 + // 定义NoteColumns的常量,用于后面创建数据库的表头 public interface NoteColumns { /** * The unique ID for a row @@ -72,7 +75,7 @@ public class Notes { * The parent's id for note or folder *

Type: INTEGER (long)

*/ - public static final String PARENT_ID = "parent_id"; + public static final String PARENT_ID = "parent_id";//为什么会有parent_id /** * Created data for note or folder @@ -140,7 +143,7 @@ public class Notes { * The last sync id *

Type: INTEGER (long)

*/ - public static final String SYNC_ID = "sync_id"; + public static final String SYNC_ID = "sync_id";//同步 /** * Sign to indicate local modified or not @@ -165,8 +168,9 @@ public class Notes { *

Type : INTEGER (long)

*/ public static final String VERSION = "version"; - } + }//这些常量主要是定义便签的属性的。 + // 定义DataColumns的常量,用于后面创建数据库的表头 public interface DataColumns { /** * The unique ID for a row @@ -239,7 +243,7 @@ public class Notes { *

Type: TEXT

*/ public static final String DATA5 = "data5"; - } + }//主要是定义存储便签内容数据的 public static final class TextNote implements DataColumns { /** @@ -255,7 +259,7 @@ public class Notes { public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/text_note"; public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note"); - } + }//文本内容的数据结构 public static final class CallNote implements DataColumns { /** @@ -275,5 +279,5 @@ public class Notes { public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/call_note"; public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/call_note"); - } + }//电话内容的数据结构 } diff --git a/src/net/micode/notes/data/NotesDatabaseHelper.java b/src/net/micode/notes/data/NotesDatabaseHelper.java index ffe5d57..e821818 100644 --- a/src/net/micode/notes/data/NotesDatabaseHelper.java +++ b/src/net/micode/notes/data/NotesDatabaseHelper.java @@ -16,23 +16,23 @@ package net.micode.notes.data; -import android.content.ContentValues; -import android.content.Context; -import android.database.sqlite.SQLiteDatabase; -import android.database.sqlite.SQLiteOpenHelper; +import android.content.ContentValues;//就是用于保存一些数据（string boolean byte double float int long short ...）信息，这些信息可以被数据库操作时使用。 +import android.content.Context;//加载和访问资源。（android中主要是这两个功能，但是这里具体不清楚） +import android.database.sqlite.SQLiteDatabase;//主要提供了对应于添加、删除、更新、查询的操作方法： insert()、delete()、update()和query()。配合content.values +import android.database.sqlite.SQLiteOpenHelper;/用来管理数据的创建和版本更新 import android.util.Log; import net.micode.notes.data.Notes.DataColumns; import net.micode.notes.data.Notes.DataConstants; import net.micode.notes.data.Notes.NoteColumns; - +//数据库操作，用SQLOpenhelper,对一些note和文件进行数据库的操作，比如删除文件后，将文件里的note也相应删除 public class NotesDatabaseHelper extends SQLiteOpenHelper { private static final String DB_NAME = "note.db"; private static final int DB_VERSION = 4; - public interface TABLE { + public interface TABLE { //接口，分成note和data，在后面的程序里分别使用过 public static final String NOTE = "note"; public static final String DATA = "data"; @@ -61,7 +61,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { NoteColumns.ORIGIN_PARENT_ID + " INTEGER NOT NULL DEFAULT 0," + NoteColumns.GTASK_ID + " TEXT NOT NULL DEFAULT ''," + NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" + - ")"; + ")";//数据库中需要存储的项目的名称，就相当于创建一个表格的表头的内容。 private static final String CREATE_DATA_TABLE_SQL = "CREATE TABLE " + TABLE.DATA + "(" + @@ -76,11 +76,11 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { DataColumns.DATA3 + " TEXT NOT NULL DEFAULT ''," + DataColumns.DATA4 + " TEXT NOT NULL DEFAULT ''," + DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" + - ")"; + ")";//和上面的功能一样，主要是存储的项目不同 private static final String CREATE_DATA_NOTE_ID_INDEX_SQL = "CREATE INDEX IF NOT EXISTS note_id_index ON " + - TABLE.DATA + "(" + DataColumns.NOTE_ID + ");"; + TABLE.DATA + "(" + DataColumns.NOTE_ID + ");";//存储便签编号的一个数据表格 /** * Increase folder's note count when move note to the folder @@ -92,7 +92,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" + " WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" + - " END"; + " END";//在文件夹中移入一个Note之后需要更改的数据的表格。 /** * Decrease folder's note count when move note from folder @@ -105,7 +105,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" + " WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID + " AND " + NoteColumns.NOTES_COUNT + ">0" + ";" + - " END"; + " END";//在文件夹中插入一个Note之后需要更改的数据的表格。 /** * Increase folder's note count when insert new note to the folder @@ -117,7 +117,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" + " WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" + - " END"; + " END";//在文件夹中删除一个Note之后需要更改的数据的表格。 /** * Decrease folder's note count when delete note from the folder @@ -130,7 +130,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" + " WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID + " AND " + NoteColumns.NOTES_COUNT + ">0;" + - " END"; + " END";//在文件夹中删除一个Note之后需要更改的数据的表格。 /** * Update note's content when insert data with type {@link DataConstants#NOTE} @@ -143,7 +143,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT + " WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" + - " END"; + " END";//在文件夹中对一个Note导入新的数据之后需要更改的数据的表格。 /** * Update note's content when data with {@link DataConstants#NOTE} type has changed @@ -156,7 +156,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT + " WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" + - " END"; + " END";//Note数据被修改后需要更改的数据的表格 /** * Update note's content when data with {@link DataConstants#NOTE} type has deleted @@ -169,7 +169,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.SNIPPET + "=''" + " WHERE " + NoteColumns.ID + "=old." + DataColumns.NOTE_ID + ";" + - " END"; + " END";//Note数据被删除后需要更改的数据的表格。 /** * Delete datas belong to note which has been deleted @@ -180,7 +180,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " BEGIN" + " DELETE FROM " + TABLE.DATA + " WHERE " + DataColumns.NOTE_ID + "=old." + NoteColumns.ID + ";" + - " END"; + " END";//删除已删除的便签的数据后需要更改的数据的表格。 /** * Delete notes belong to folder which has been deleted @@ -191,7 +191,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " BEGIN" + " DELETE FROM " + TABLE.NOTE + " WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" + - " END"; + " END";//删除已删除的文件夹的便签后需要更改的数据的表格。 /** * Move notes belong to folder which has been moved to trash folder @@ -204,18 +204,18 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " UPDATE " + TABLE.NOTE + " SET " + NoteColumns.PARENT_ID + "=" + Notes.ID_TRASH_FOLER + " WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" + - " END"; + " END";//还原垃圾桶中便签后需要更改的数据的表格。 public NotesDatabaseHelper(Context context) { super(context, DB_NAME, null, DB_VERSION); - } + }//构造函数，传入数据库的名称和版本 public void createNoteTable(SQLiteDatabase db) { db.execSQL(CREATE_NOTE_TABLE_SQL); reCreateNoteTableTriggers(db); createSystemFolder(db); Log.d(TAG, "note table has been created"); - } + }//创建表格（用来存储标签属性） private void reCreateNoteTableTriggers(SQLiteDatabase db) { db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_update"); @@ -233,7 +233,8 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { db.execSQL(NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER); db.execSQL(FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER); db.execSQL(FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER); - } + }//execSQL是数据库操作的API，主要是更改行为的SQL语句。 + //在这里主要是用来重新创建上述定义的表格用的，先删除原来有的数据库的触发器再重新创建新的数据库 private void createSystemFolder(SQLiteDatabase db) { ContentValues values = new ContentValues(); @@ -268,14 +269,14 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER); values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM); db.insert(TABLE.NOTE, null, values); - } + }//创建几个系统文件夹 public void createDataTable(SQLiteDatabase db) { db.execSQL(CREATE_DATA_TABLE_SQL); reCreateDataTableTriggers(db); db.execSQL(CREATE_DATA_NOTE_ID_INDEX_SQL); Log.d(TAG, "data table has been created"); - } + }//创建表格（用来存储标签内容） private void reCreateDataTableTriggers(SQLiteDatabase db) { db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_insert"); @@ -285,20 +286,22 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { 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); - } + }//同上面的execSQL static synchronized NotesDatabaseHelper getInstance(Context context) { if (mInstance == null) { mInstance = new NotesDatabaseHelper(context); } return mInstance; - } + }//上网查是为解决同一时刻只能有一个线程执行. + //在写程序库代码时，有时有一个类需要被所有的其它类使用， + //但又要求这个类只能被实例化一次，是个服务类，定义一次，其它类使用同一个这个类的实例 @Override public void onCreate(SQLiteDatabase db) { createNoteTable(db); createDataTable(db); - } + }//实现两个表格（上面创建的两个表格） @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { @@ -331,14 +334,14 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { throw new IllegalStateException("Upgrade notes database to version " + newVersion + "fails"); } - } + }//数据库版本的更新（数据库内容的更改） private void upgradeToV2(SQLiteDatabase db) { db.execSQL("DROP TABLE IF EXISTS " + TABLE.NOTE); db.execSQL("DROP TABLE IF EXISTS " + TABLE.DATA); createNoteTable(db); createDataTable(db); - } + }//更新到V2版本 private void upgradeToV3(SQLiteDatabase db) { // drop unused triggers @@ -353,10 +356,10 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER); values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM); db.insert(TABLE.NOTE, null, values); - } + }//更新到V3版本 private void upgradeToV4(SQLiteDatabase db) { db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0"); - } + }//更新到V4版本,但是不知道V2、V3、V4是什么意思 } diff --git a/src/net/micode/notes/data/NotesProvider.java b/src/net/micode/notes/data/NotesProvider.java index edb0a60..e1c9fca 100644 --- a/src/net/micode/notes/data/NotesProvider.java +++ b/src/net/micode/notes/data/NotesProvider.java @@ -34,7 +34,13 @@ import net.micode.notes.data.Notes.DataColumns; import net.micode.notes.data.Notes.NoteColumns; import net.micode.notes.data.NotesDatabaseHelper.TABLE; - +//为存储和获取数据提供接口。可以在不同的应用程序之间共享数据 +//ContentProvider提供的方法 +//query：查询 +//insert：插入 +//update：更新 +//delete：删除 +//getType：得到数据类型 public class NotesProvider extends ContentProvider { private static final UriMatcher mMatcher; @@ -50,8 +56,9 @@ public class NotesProvider extends ContentProvider { private static final int URI_SEARCH = 5; private static final int URI_SEARCH_SUGGEST = 6; - static { + static {// 创建UriMatcher时，调用UriMatcher(UriMatcher.NO_MATCH)表示不匹配任何路径的返回码 mMatcher = new UriMatcher(UriMatcher.NO_MATCH); + // 把需要匹配Uri路径全部给注册上 mMatcher.addURI(Notes.AUTHORITY, "note", URI_NOTE); mMatcher.addURI(Notes.AUTHORITY, "note/#", URI_NOTE_ITEM); mMatcher.addURI(Notes.AUTHORITY, "data", URI_DATA); @@ -65,6 +72,7 @@ public class NotesProvider extends ContentProvider { * x'0A' represents the '\n' character in sqlite. For title and content in the search result, * we will trim '\n' and white space in order to show more information. */ + // 声明 NOTES_SEARCH_PROJECTION private static final String NOTES_SEARCH_PROJECTION = NoteColumns.ID + "," + NoteColumns.ID + " AS " + SearchManager.SUGGEST_COLUMN_INTENT_EXTRA_DATA + "," + "TRIM(REPLACE(" + NoteColumns.SNIPPET + ", x'0A','')) AS " + SearchManager.SUGGEST_COLUMN_TEXT_1 + "," @@ -73,6 +81,7 @@ public class NotesProvider extends ContentProvider { + "'" + Intent.ACTION_VIEW + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_ACTION + "," + "'" + Notes.TextNote.CONTENT_TYPE + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_DATA; + // 声明NOTES_SNIPPET_SEARCH_QUERY private static String NOTES_SNIPPET_SEARCH_QUERY = "SELECT " + NOTES_SEARCH_PROJECTION + " FROM " + TABLE.NOTE + " WHERE " + NoteColumns.SNIPPET + " LIKE ?" @@ -80,18 +89,24 @@ public class NotesProvider extends ContentProvider { + " AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE; @Override + // Context只有在onCreate()中才被初始化 + // 对mHelper进行实例化 public boolean onCreate() { mHelper = NotesDatabaseHelper.getInstance(getContext()); return true; } @Override + // 查询uri在数据库中对应的位置 public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { Cursor c = null; + // 获取可读数据库 SQLiteDatabase db = mHelper.getReadableDatabase(); String id = null; + // 匹配查找uri switch (mMatcher.match(uri)) { + // 对于不同的匹配值，在数据库中查找相应的条目 case URI_NOTE: c = db.query(TABLE.NOTE, projection, selection, selectionArgs, null, null, sortOrder); @@ -113,6 +128,7 @@ public class NotesProvider extends ContentProvider { case URI_SEARCH: case URI_SEARCH_SUGGEST: if (sortOrder != null || projection != null) { + // 不合法的参数异常 throw new IllegalArgumentException( "do not specify sortOrder, selection, selectionArgs, or projection" + "with this query"); } @@ -120,6 +136,8 @@ public class NotesProvider extends ContentProvider { String searchString = null; if (mMatcher.match(uri) == URI_SEARCH_SUGGEST) { if (uri.getPathSegments().size() > 1) { + // getPathSegments()方法得到一个String的List， + // 在uri.getPathSegments().get(1)为第2个元素 searchString = uri.getPathSegments().get(1); } } else { @@ -139,6 +157,7 @@ public class NotesProvider extends ContentProvider { } break; default: + // 抛出异常 throw new IllegalArgumentException("Unknown URI " + uri); } if (c != null) { @@ -148,13 +167,17 @@ public class NotesProvider extends ContentProvider { } @Override + // 插入一个uri public Uri insert(Uri uri, ContentValues values) { + // 获得可写的数据库 SQLiteDatabase db = mHelper.getWritableDatabase(); long dataId = 0, noteId = 0, insertedId = 0; switch (mMatcher.match(uri)) { + // 新增一个条目 case URI_NOTE: insertedId = noteId = db.insert(TABLE.NOTE, null, values); break; + // 如果存在，查找NOTE_ID case URI_DATA: if (values.containsKey(DataColumns.NOTE_ID)) { noteId = values.getAsLong(DataColumns.NOTE_ID); @@ -167,6 +190,7 @@ public class NotesProvider extends ContentProvider { throw new IllegalArgumentException("Unknown URI " + uri); } // Notify the note uri + // notifyChange获得一个ContextResolver对象并且更新里面的内容 if (noteId > 0) { getContext().getContentResolver().notifyChange( ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), null); @@ -177,14 +201,17 @@ public class NotesProvider extends ContentProvider { getContext().getContentResolver().notifyChange( ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId), null); } - + // 返回插入的uri的路径 return ContentUris.withAppendedId(uri, insertedId); } @Override + // 删除一个uri public int delete(Uri uri, String selection, String[] selectionArgs) { + //Uri代表要操作的数据，Android上可用的每种资源 -包括 图像、视频片段、音频资源等都可以用Uri来表示。 int count = 0; String id = null; + // 获得可写的数据库 SQLiteDatabase db = mHelper.getWritableDatabase(); boolean deleteData = false; switch (mMatcher.match(uri)) { @@ -228,6 +255,7 @@ public class NotesProvider extends ContentProvider { } @Override + // 更新一个uri public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { int count = 0; String id = null; @@ -267,10 +295,11 @@ public class NotesProvider extends ContentProvider { return count; } + // 将字符串解析成规定格式 private String parseSelection(String selection) { return (!TextUtils.isEmpty(selection) ? " AND (" + selection + ')' : ""); } - + //增加一个noteVersion private void increaseNoteVersion(long id, String selection, String[] selectionArgs) { StringBuilder sql = new StringBuilder(120); sql.append("UPDATE "); @@ -292,7 +321,7 @@ public class NotesProvider extends ContentProvider { } sql.append(selectString); } - + // execSQL()方法可以执行insert、delete、update和CREATE TABLE之类有更改行为的SQL语句 mHelper.getWritableDatabase().execSQL(sql.toString()); } diff --git a/src/net/micode/notes/tool/BackupUtils.java b/src/net/micode/notes/tool/BackupUtils.java index 39f6ec4..da1a5fd 100644 --- a/src/net/micode/notes/tool/BackupUtils.java +++ b/src/net/micode/notes/tool/BackupUtils.java @@ -37,12 +37,16 @@ import java.io.PrintStream; public class BackupUtils { - private static final String TAG = "BackupUtils"; + private static final String TAG = "BackupUtils"; //类里面为什么可以定义自身类的对象？ // Singleton stuff private static BackupUtils sInstance; public static synchronized BackupUtils getInstance(Context context) { + //ynchronized 关键字，代表这个方法加锁,相当于不管哪一个线程（例如线程A） + //运行到这个方法时,都要检查有没有其它线程B（或者C、 D等）正在用这个方法(或者该类的其他同步方法)，有的话要等正在使用synchronized方法的线程B（或者C 、D）运行完这个方法后再运行此线程A,没有的话,锁定调用者,然后直接运行。 + //它包括两种用法：synchronized 方法和 synchronized 块。 if (sInstance == null) { + //如果当前备份不存在，则新声明一个 sInstance = new BackupUtils(context); } return sInstance; @@ -52,24 +56,26 @@ public class BackupUtils { * Following states are signs to represents backup or restore * status */ - // Currently, the sdcard is not mounted + // Currently, the sdcard is not mounted SD 卡没有被装入手机 public static final int STATE_SD_CARD_UNMOUONTED = 0; - // The backup file not exist + // The backup file not exist 备份文件夹不存在 public static final int STATE_BACKUP_FILE_NOT_EXIST = 1; - // The data is not well formated, may be changed by other programs + // The data is not well formated, may be changed by other programs 数据已被破坏，可能被修改 public static final int STATE_DATA_DESTROIED = 2; - // Some run-time exception which causes restore or backup fails + // Some run-time exception which causes restore or backup fails 超时异常 public static final int STATE_SYSTEM_ERROR = 3; - // Backup or restore success + // Backup or restore success 成功存储 public static final int STATE_SUCCESS = 4; private TextExport mTextExport; + //初始化函数 private BackupUtils(Context context) { mTextExport = new TextExport(context); } private static boolean externalStorageAvailable() { + //外部存储功能是否可用 return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()); } @@ -128,10 +134,11 @@ public class BackupUtils { public TextExport(Context context) { TEXT_FORMAT = context.getResources().getStringArray(R.array.format_for_exported_note); mContext = context; - mFileName = ""; + mFileName = ""; //为什么为空? mFileDirectory = ""; } + //获取文本的组成部分 private String getFormat(int id) { return TEXT_FORMAT[id]; } @@ -140,7 +147,7 @@ public class BackupUtils { * Export the folder identified by folder id to text */ private void exportFolderToText(String folderId, PrintStream ps) { - // Query notes belong to this folder + // Query notes belong to this folder 通过查询parent id是文件夹id的note来选出制定ID文件夹下的Note Cursor notesCursor = mContext.getContentResolver().query(Notes.CONTENT_NOTE_URI, NOTE_PROJECTION, NoteColumns.PARENT_ID + "=?", new String[] { folderId @@ -149,13 +156,13 @@ public class BackupUtils { if (notesCursor != null) { if (notesCursor.moveToFirst()) { do { - // Print note's last modified date + // Print note's last modified date ps里面保存有这份note的日期 ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format( mContext.getString(R.string.format_datetime_mdhm), notesCursor.getLong(NOTE_COLUMN_MODIFIED_DATE)))); // Query data belong to this note String noteId = notesCursor.getString(NOTE_COLUMN_ID); - exportNoteToText(noteId, ps); + exportNoteToText(noteId, ps); //将文件导出到text } while (notesCursor.moveToNext()); } notesCursor.close(); @@ -172,6 +179,7 @@ public class BackupUtils { }, null); if (dataCursor != null) { + //利用光标来扫描内容，区别为callnote和note两种，靠ps.printline输出 if (dataCursor.moveToFirst()) { do { String mimeType = dataCursor.getString(DATA_COLUMN_MIME_TYPE); @@ -181,7 +189,7 @@ public class BackupUtils { long callDate = dataCursor.getLong(DATA_COLUMN_CALL_DATE); String location = dataCursor.getString(DATA_COLUMN_CONTENT); - if (!TextUtils.isEmpty(phoneNumber)) { + if (!TextUtils.isEmpty(phoneNumber)) { //判断是否为空字符 ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), phoneNumber)); } @@ -218,7 +226,7 @@ public class BackupUtils { /** * Note will be exported as text which is user readable */ - public int exportToText() { + public int exportToText() { //总函数，调用上面的exportFolder和exportNote if (!externalStorageAvailable()) { Log.d(TAG, "Media was not mounted"); return STATE_SD_CARD_UNMOUONTED; @@ -229,7 +237,7 @@ public class BackupUtils { Log.e(TAG, "get print stream error"); return STATE_SYSTEM_ERROR; } - // First export folder and its notes + // First export folder and its notes 导出文件夹，就是导出里面包含的便签 Cursor folderCursor = mContext.getContentResolver().query( Notes.CONTENT_NOTE_URI, NOTE_PROJECTION, @@ -257,7 +265,7 @@ public class BackupUtils { folderCursor.close(); } - // Export notes in root's folder + // Export notes in root's folder 将根目录里的便签导出（由于不属于任何文件夹，因此无法通过文件夹导出来实现这一部分便签的导出） Cursor noteCursor = mContext.getContentResolver().query( Notes.CONTENT_NOTE_URI, NOTE_PROJECTION, @@ -297,7 +305,7 @@ public class BackupUtils { PrintStream ps = null; try { FileOutputStream fos = new FileOutputStream(file); - ps = new PrintStream(fos); + ps = new PrintStream(fos); //将ps输出流输出到特定的文件，目的就是导出到文件，而不是直接输出 } catch (FileNotFoundException e) { e.printStackTrace(); return null; @@ -314,16 +322,16 @@ public class BackupUtils { */ private static File generateFileMountedOnSDcard(Context context, int filePathResId, int fileNameFormatResId) { StringBuilder sb = new StringBuilder(); - sb.append(Environment.getExternalStorageDirectory()); - sb.append(context.getString(filePathResId)); - File filedir = new File(sb.toString()); + sb.append(Environment.getExternalStorageDirectory()); //外部（SD卡）的存储路径 + sb.append(context.getString(filePathResId)); //文件的存储路径 + File filedir = new File(sb.toString()); //filedir应该就是用来存储路径信息 sb.append(context.getString( fileNameFormatResId, DateFormat.format(context.getString(R.string.format_date_ymd), System.currentTimeMillis()))); File file = new File(sb.toString()); - try { + try { //如果这些文件不存在，则新建 if (!filedir.exists()) { filedir.mkdir(); } @@ -336,7 +344,7 @@ public class BackupUtils { } catch (IOException e) { e.printStackTrace(); } - + // try catch 异常处理 return null; } } diff --git a/src/net/micode/notes/tool/DataUtils.java b/src/net/micode/notes/tool/DataUtils.java index 2a14982..279c684 100644 --- a/src/net/micode/notes/tool/DataUtils.java +++ b/src/net/micode/notes/tool/DataUtils.java @@ -38,6 +38,7 @@ import java.util.HashSet; public class DataUtils { public static final String TAG = "DataUtils"; public static boolean batchDeleteNotes(ContentResolver resolver, HashSet ids) { + //直接删除多个笔记 if (ids == null) { Log.d(TAG, "the ids is null"); return true; @@ -47,18 +48,19 @@ public class DataUtils { return true; } - ArrayList operationList = new ArrayList(); + ArrayList operationList = new ArrayList(); //提供一个任务列表 for (long id : ids) { if(id == Notes.ID_ROOT_FOLDER) { Log.e(TAG, "Don't delete system folder root"); continue; - } + } //如果发现是根文件夹，则不删除 ContentProviderOperation.Builder builder = ContentProviderOperation - .newDelete(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id)); + .newDelete(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id)); //用newDelete实现删除功能 operationList.add(builder.build()); } try { - ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList); + ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList); //主机名（或叫Authority）用于唯一标识这个ContentProvider，外部调用者可以根据这个标识来找到它。 + //数据库事务，数据库事务是由一组数据库操作序列组成，事务作为一个整体被执行 if (results == null || results.length == 0 || results[0] == null) { Log.d(TAG, "delete notes failed, ids:" + ids.toString()); return false; @@ -77,7 +79,7 @@ public class DataUtils { values.put(NoteColumns.PARENT_ID, desFolderId); values.put(NoteColumns.ORIGIN_PARENT_ID, srcFolderId); values.put(NoteColumns.LOCAL_MODIFIED, 1); - resolver.update(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id), values, null, null); + resolver.update(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id), values, null, null); //对需要移动的便签进行数据更新，然后用update实现 } public static boolean batchMoveToFolder(ContentResolver resolver, HashSet ids, @@ -90,14 +92,14 @@ public class DataUtils { ArrayList operationList = new ArrayList(); for (long id : ids) { ContentProviderOperation.Builder builder = ContentProviderOperation - .newUpdate(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id)); + .newUpdate(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id)); //通过withAppendedId方法，为该Uri加上ID builder.withValue(NoteColumns.PARENT_ID, folderId); builder.withValue(NoteColumns.LOCAL_MODIFIED, 1); operationList.add(builder.build()); - } + } //将ids里包含的每一列的数据逐次加入到operationList中，等待最后的批量处理 try { - ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList); + ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList) //applyBatch一次性处理一个操作列表 if (results == null || results.length == 0 || results[0] == null) { Log.d(TAG, "delete notes failed, ids:" + ids.toString()); return false; @@ -119,7 +121,7 @@ public class DataUtils { new String[] { "COUNT(*)" }, NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>?", new String[] { String.valueOf(Notes.TYPE_FOLDER), String.valueOf(Notes.ID_TRASH_FOLER)}, - null); + null); //筛选条件：源文件不为trash folder int count = 0; if(cursor != null) { @@ -137,15 +139,15 @@ public class DataUtils { } public static boolean visibleInNoteDatabase(ContentResolver resolver, long noteId, int type) { - Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), + Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), //通过withAppendedId方法，为该Uri加上ID null, NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER, new String [] {String.valueOf(type)}, - null); + null); //查询条件：type符合，且不属于垃圾文件夹 boolean exist = false; if (cursor != null) { - if (cursor.getCount() > 0) { + if (cursor.getCount() > 0) { //用getcount函数判断cursor是否为空 exist = true; } cursor.close(); @@ -187,6 +189,7 @@ public class DataUtils { " AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER + " AND " + NoteColumns.SNIPPET + "=?", new String[] { name }, null); + //通过名字查询文件是否存在 boolean exist = false; if(cursor != null) { if(cursor.getCount() > 0) { @@ -202,7 +205,7 @@ public class DataUtils { new String[] { NoteColumns.WIDGET_ID, NoteColumns.WIDGET_TYPE }, NoteColumns.PARENT_ID + "=?", new String[] { String.valueOf(folderId) }, - null); + null); //查询条件：父ID是传入的folderId; HashSet set = null; if (c != null) { @@ -217,7 +220,7 @@ public class DataUtils { } catch (IndexOutOfBoundsException e) { Log.e(TAG, e.toString()); } - } while (c.moveToNext()); + } while (c.moveToNext()); //查询下一条 } c.close(); } @@ -250,7 +253,7 @@ public class DataUtils { + CallNote.PHONE_NUMBER + ",?)", new String [] { String.valueOf(callDate), CallNote.CONTENT_ITEM_TYPE, phoneNumber }, null); - + //通过数据库操作，查询条件是（callDate和phoneNumber匹配传入参数的值） if (cursor != null) { if (cursor.moveToFirst()) { try { @@ -269,7 +272,7 @@ public class DataUtils { new String [] { NoteColumns.SNIPPET }, NoteColumns.ID + "=?", new String [] { String.valueOf(noteId)}, - null); + null); //查询条件：noteId if (cursor != null) { String snippet = ""; @@ -282,7 +285,8 @@ public class DataUtils { throw new IllegalArgumentException("Note is not found with id: " + noteId); } - public static String getFormattedSnippet(String snippet) { + public static String getFormattedSnippet(String snippet){ + //对字符串进行格式处理，将字符串两头的空格去掉，同时将换行符去掉 if (snippet != null) { snippet = snippet.trim(); int index = snippet.indexOf('\n'); diff --git a/src/net/micode/notes/tool/GTaskStringUtils.java b/src/net/micode/notes/tool/GTaskStringUtils.java index 666b729..9f69faf 100644 --- a/src/net/micode/notes/tool/GTaskStringUtils.java +++ b/src/net/micode/notes/tool/GTaskStringUtils.java @@ -13,9 +13,17 @@ * See the License for the specific language governing permissions and * limitations under the License. */ +/* + 简介：定义了很多的静态字符串，目的就是为了提供jsonObject中相应字符串的"key"。 + 把这些静态的定义单独写到了一个类里面，这是非常好的编程规范 +*/ package net.micode.notes.tool; +/* + 这个类就是定义了一堆static string，实际就是为jsonObject提供Key， + 把这些定义全部写到一个类里，方便查看管理，是一个非常好的编程习惯 +*/ public class GTaskStringUtils { public final static String GTASK_JSON_ACTION_ID = "action_id"; diff --git a/src/net/micode/notes/tool/ResourceParser.java b/src/net/micode/notes/tool/ResourceParser.java index 1ad3ad6..4dd4cb2 100644 --- a/src/net/micode/notes/tool/ResourceParser.java +++ b/src/net/micode/notes/tool/ResourceParser.java @@ -15,7 +15,20 @@ */ package net.micode.notes.tool; - +/*简介：字面意义是资源分析器，实际上就是获取资源并且在程序中使用，比如颜色图片等 + * 实现方法：主要利用R.java这个类，其中包括 + * R.id 组件资源引用 + * R.drawable 图片资源 （被使用） + * R.layout 布局资源 + * R.menu 菜单资源 + * R.String 文字资源 + * R.style 主题资源 （被使用） + * 在按顺序设置好相应的id后，就可以编写简单的getXXX函数获取需要的资源 + * + * 特殊的变量 ： + * @BG_DEFAULT_COLOR 默认背景颜色（黄） + * BG_DEFAULT_FONT_SIZE 默认文本大小（中） + */ import android.content.Context; import android.preference.PreferenceManager; @@ -65,6 +78,7 @@ public class ResourceParser { } } + //直接获取默认的背景颜色。看不太懂，这个PREFERENCE_SET_BG_COLOR_KEY是个final string,也就是说getBoolean肯定执行else，为什么要这么写 public static int getDefaultBgId(Context context) { if (PreferenceManager.getDefaultSharedPreferences(context).getBoolean( NotesPreferenceActivity.PREFERENCE_SET_BG_COLOR_KEY, false)) { @@ -162,6 +176,7 @@ public class ResourceParser { R.style.TextAppearanceSuper }; + //这里有一个容错的函数，防止输入的id大于资源总量，若如此，则自动返回默认的设置结果 public static int getTexAppearanceResource(int id) { /** * HACKME: Fix bug of store the resource id in shared preference.