添加部分注释

Notes-master/app/src/main/java/net/micode/notes/tool/BackupUtils.java

@@ -42,7 +42,7 @@ public class BackupUtils {
     private static BackupUtils sInstance;
 
     public static synchronized BackupUtils getInstance(Context context) {
-        if (sInstance == null) {
+        if (sInstance == null) {//如果当前备份不存在，则声明一个
             sInstance = new BackupUtils(context);
         }
         return sInstance;
@@ -67,7 +67,7 @@ public class BackupUtils {
 
     private BackupUtils(Context context) {
         mTextExport = new TextExport(context);
-    }
+    }//初始化函数
 
     private static boolean externalStorageAvailable() {
         return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
@@ -140,7 +140,7 @@ 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 +149,13 @@ 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();
@@ -171,21 +171,21 @@ public class BackupUtils {
                         noteId
                     }, null);
 
-            if (dataCursor != null) {
+            if (dataCursor != null) {//利用光标来扫描内容，区别位callnote和note两种
                 if (dataCursor.moveToFirst()) {
                     do {
                         String mimeType = dataCursor.getString(DATA_COLUMN_MIME_TYPE);
                         if (DataConstants.CALL_NOTE.equals(mimeType)) {
-                            // Print phone number
+                            // Print phone number 打印电话号码
                             String phoneNumber = dataCursor.getString(DATA_COLUMN_PHONE_NUMBER);
                             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));
                             }
-                            // Print call date
+                            // Print call date 打印呼叫日期
                             ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), DateFormat
                                     .format(mContext.getString(R.string.format_datetime_mdhm),
                                             callDate)));
@@ -217,9 +217,10 @@ public class BackupUtils {
 
         /**
          * Note will be exported as text which is user readable
+         * note 将被导出为文本，用户可见
          */
         public int exportToText() {
-            if (!externalStorageAvailable()) {
+            if (!externalStorageAvailable()) { //总函数，调用上面的exportFolder和exportNote
                 Log.d(TAG, "Media was not mounted");
                 return STATE_SD_CARD_UNMOUONTED;
             }
@@ -229,7 +230,7 @@ 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，导出里面包含的便签
             Cursor folderCursor = mContext.getContentResolver().query(
                     Notes.CONTENT_NOTE_URI,
                     NOTE_PROJECTION,
@@ -257,7 +258,7 @@ public class BackupUtils {
                 folderCursor.close();
             }
 
-            // Export notes in root's folder
+            // Export notes in root's folder    ，将根目录里面的便签导出
             Cursor noteCursor = mContext.getContentResolver().query(
                     Notes.CONTENT_NOTE_URI,
                     NOTE_PROJECTION,
@@ -297,7 +298,7 @@ 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，而部署直接输出
             } catch (FileNotFoundException e) {
                 e.printStackTrace();
                 return null;
@@ -314,9 +315,9 @@ public class BackupUtils {
      */
     private static File generateFileMountedOnSDcard(Context context, int filePathResId, int fileNameFormatResId) {
         StringBuilder sb = new StringBuilder();
-        sb.append(Environment.getExternalStorageDirectory());
+        sb.append(Environment.getExternalStorageDirectory());//外部（SD卡）的存储路径
-        sb.append(context.getString(filePathResId));
+        sb.append(context.getString(filePathResId));//文件的存储路径
-        File filedir = new File(sb.toString());
+        File filedir = new File(sb.toString());//filedir存储路径信息
         sb.append(context.getString(
                 fileNameFormatResId,
                 DateFormat.format(context.getString(R.string.format_date_ymd),
@@ -324,7 +325,7 @@ public class BackupUtils {
         File file = new File(sb.toString());
 
         try {
-            if (!filedir.exists()) {
+            if (!filedir.exists()) {//文件不存在，则新建文件
                 filedir.mkdir();
             }
             if (!file.exists()) {

Notes-master/app/src/main/java/net/micode/notes/tool/DataUtils.java

@@ -37,7 +37,7 @@ import java.util.HashSet;
 
 public class DataUtils {
     public static final String TAG = "DataUtils";
-    public static boolean batchDeleteNotes(ContentResolver resolver, HashSet<Long> ids) {
+    public static boolean batchDeleteNotes(ContentResolver resolver, HashSet<Long> ids) {//直接删除多个笔记
         if (ids == null) {
             Log.d(TAG, "the ids is null");
             return true;
@@ -47,9 +47,9 @@ public class DataUtils {
             return true;
         }
 
-        ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
+        ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();//提供一个任务列表
         for (long id : ids) {
-            if(id == Notes.ID_ROOT_FOLDER) {
+            if(id == Notes.ID_ROOT_FOLDER) {//若为根文件夹，则警告不可删除
                 Log.e(TAG, "Don't delete system folder root");
                 continue;
             }