diff --git a/app/src/main/java/net/micode/notes/data/Contact.java b/app/src/main/java/net/micode/notes/data/Contact.java index 9c6fa62..79886e8 100644 --- a/app/src/main/java/net/micode/notes/data/Contact.java +++ b/app/src/main/java/net/micode/notes/data/Contact.java @@ -25,46 +25,54 @@ import android.util.Log; import java.util.HashMap; +/** + * 联系人 + */ public class Contact { 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 " + "(SELECT raw_contact_id " + " 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}, selection, 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); return null; diff --git a/app/src/main/java/net/micode/notes/data/Notes.java b/app/src/main/java/net/micode/notes/data/Notes.java index 87e60c3..bfda0f9 100644 --- a/app/src/main/java/net/micode/notes/data/Notes.java +++ b/app/src/main/java/net/micode/notes/data/Notes.java @@ -26,6 +26,7 @@ import android.net.Uri; 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; @@ -172,7 +173,7 @@ public class Notes { */ public static final String VERSION = "version"; } - + // 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 @@ -245,7 +246,7 @@ 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 { /** @@ -261,7 +262,7 @@ 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 { /** @@ -281,5 +282,5 @@ 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/app/src/main/java/net/micode/notes/data/NotesDatabaseHelper.java b/app/src/main/java/net/micode/notes/data/NotesDatabaseHelper.java index c7d668e..8b015ce 100644 --- a/app/src/main/java/net/micode/notes/data/NotesDatabaseHelper.java +++ b/app/src/main/java/net/micode/notes/data/NotesDatabaseHelper.java @@ -32,7 +32,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { 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";//在文件夹中移出一个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";//在文件夹中插入一个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"); - } + }//构造函数，传入数据库的名称和版本 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) { @@ -331,7 +334,7 @@ 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); diff --git a/app/src/main/java/net/micode/notes/data/NotesProvider.java b/app/src/main/java/net/micode/notes/data/NotesProvider.java index 51d2ff9..c7ab807 100644 --- a/app/src/main/java/net/micode/notes/data/NotesProvider.java +++ b/app/src/main/java/net/micode/notes/data/NotesProvider.java @@ -34,8 +34,17 @@ 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 + * update：更新 + * getType：得到数据类型 + */ public class NotesProvider extends ContentProvider { + // UriMatcher用于匹配Uri private static final UriMatcher mMatcher; private NotesDatabaseHelper mHelper; @@ -51,7 +60,9 @@ public class NotesProvider extends ContentProvider { private static final int URI_SEARCH_SUGGEST = 6; 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); + // 创建UriMatcher时，调用UriMatcher(UriMatcher.NO_MATCH)表示不匹配任何路径的返回码 mMatcher.addURI(Notes.AUTHORITY, "note", URI_NOTE); mMatcher.addURI(Notes.AUTHORITY, "note/#", URI_NOTE_ITEM); mMatcher.addURI(Notes.AUTHORITY, "data", URI_DATA); @@ -80,18 +91,24 @@ 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 +130,7 @@ 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 +138,8 @@ 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 +159,7 @@ public class NotesProvider extends ContentProvider { } break; default: + //抛出异常 throw new IllegalArgumentException("Unknown URI " + uri); } if (c != null) { @@ -148,7 +169,9 @@ public class NotesProvider extends ContentProvider { } @Override + // 插入一个uri public Uri insert(Uri uri, ContentValues values) { + // 插入一个uri SQLiteDatabase db = mHelper.getWritableDatabase(); long dataId = 0, noteId = 0, insertedId = 0; switch (mMatcher.match(uri)) { @@ -183,8 +206,10 @@ public class NotesProvider extends ContentProvider { @Override 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)) { @@ -266,11 +291,11 @@ 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 +317,7 @@ 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()); }