new

src/NoteEditActivity.java

@@ -525,19 +525,21 @@ public class NoteEditActivity extends Activity implements OnClickListener,
                 break;
                 // 其他菜单项处理...
             case R.id.menu_delete:
+                // 用户点击删除菜单项
+                // 弹出确认删除对话框
                 AlertDialog.Builder builder = new AlertDialog.Builder(this);
-                builder.setTitle(getString(R.string.alert_title_delete));
-                builder.setIcon(android.R.drawable.ic_dialog_alert);
-                builder.setMessage(getString(R.string.alert_message_delete_note));
-                builder.setPositiveButton(android.R.string.ok,
+                builder.setTitle(getString(R.string.alert_title_delete));// 设置对话框标题
+                builder.setIcon(android.R.drawable.ic_dialog_alert);// 设置对话框图标
+                builder.setMessage(getString(R.string.alert_message_delete_note));//设置对话框消息
+                builder.setPositiveButton(android.R.string.ok,// 设置“确定”按钮
                         new DialogInterface.OnClickListener() {
                             public void onClick(DialogInterface dialog, int which) {
-                                deleteCurrentNote();
-                                finish();
+                                deleteCurrentNote(); // 调用删除便签方法
+                                finish();// 结束当前活动
                             }
                         });
-                builder.setNegativeButton(android.R.string.cancel, null);
-                builder.show();
+                builder.setNegativeButton(android.R.string.cancel, null);// 设置“取消”按钮
+                builder.show();// 显示对话框
                 break;
             case R.id.menu_font_size:
                 mFontSizeSelector.setVisibility(View.VISIBLE);
@@ -602,25 +604,29 @@ public class NoteEditActivity extends Activity implements OnClickListener,
     }
 
     private void deleteCurrentNote() {
-        if (mWorkingNote.existInDatabase()) {
-            HashSet<Long> ids = new HashSet<Long>();
-            long id = mWorkingNote.getNoteId();
-            if (id != Notes.ID_ROOT_FOLDER) {
-                ids.add(id);
+        if (mWorkingNote.existInDatabase()) {// 检查便签是否存在于数据库中
+            HashSet<Long> ids = new HashSet<Long>();// 创建一个集合存储要删除的便签ID
+            long id = mWorkingNote.getNoteId();// 获取当前编辑的便签ID
+            if (id != Notes.ID_ROOT_FOLDER) {// 排除根文件夹ID（非法ID）
+                ids.add(id);// 将便签ID添加到集合中
             } else {
                 Log.d(TAG, "Wrong note id, should not happen");
+                // 日志记录，不应该出现的情况
             }
-            if (!isSyncMode()) {
+            if (!isSyncMode()) {// 判断是否处于同步模式
                 if (!DataUtils.batchDeleteNotes(getContentResolver(), ids)) {
-                    Log.e(TAG, "Delete Note error");
+                    // 调用工具类批量删除便签
+                    Log.e(TAG, "Delete Note error");// 删除失败，记录错误日志
                 }
             } else {
                 if (!DataUtils.batchMoveToFolder(getContentResolver(), ids, Notes.ID_TRASH_FOLER)) {
+                    // 同步模式下，将便签移动到回收站文件夹
                     Log.e(TAG, "Move notes to trash folder error, should not happens");
+                    // 移动失败，记录错误日志
                 }
             }
         }
-        mWorkingNote.markDeleted(true);
+        mWorkingNote.markDeleted(true);// 标记便签为已删除
     }
 
     private boolean isSyncMode() {

src/NotesDatabaseHelper.java

@@ -216,10 +216,11 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
     }
 
     public void createNoteTable(SQLiteDatabase db) {
-        db.execSQL(CREATE_NOTE_TABLE_SQL);
-        reCreateNoteTableTriggers(db);
-        createSystemFolder(db);
+        db.execSQL(CREATE_NOTE_TABLE_SQL);// 执行创建便签表的SQL语句
+        reCreateNoteTableTriggers(db);// 重新创建便签表的触发器
+        createSystemFolder(db);// 创建系统文件夹
         Log.d(TAG, "note table has been created");
+        // 日志记录，便签表创建完成
     }
 
     private void reCreateNoteTableTriggers(SQLiteDatabase db) {
@@ -276,10 +277,10 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
     }
 
     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");
+        db.execSQL(CREATE_DATA_TABLE_SQL);// 执行创建数据表的SQL语句
+        reCreateDataTableTriggers(db); // 重新创建数据表的触发器
+        db.execSQL(CREATE_DATA_NOTE_ID_INDEX_SQL);// 创建数据表的索引
+        Log.d(TAG, "data table has been created"); // 日志记录，数据表创建完成
     }
 
     private void reCreateDataTableTriggers(SQLiteDatabase db) {
@@ -301,8 +302,8 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper {
 
     @Override
     public void onCreate(SQLiteDatabase db) {
-        createNoteTable(db);
-        createDataTable(db);
+        createNoteTable(db);// 创建便签表
+        createDataTable(db);// 创建数据表
     }
 
     @Override

src/NotesProvider.java

@@ -192,15 +192,17 @@ public class NotesProvider extends ContentProvider {
 
     @Override
     public int delete(Uri uri, String selection, String[] selectionArgs) {
-        int count = 0;
-        String id = null;
+        int count = 0;// 用于记录删除的数据条数
+        String id = null;// 用于存储从Uri中解析出的ID
         SQLiteDatabase db = mHelper.getWritableDatabase();
-        boolean deleteData = false;
-        switch (mMatcher.match(uri)) {
+        // 获取可写的数据库对象
+        boolean deleteData = false;// 标记是否需要删除数据表中的记录
+        switch (mMatcher.match(uri)) { // 根据Uri匹配对应的处理逻辑
             case URI_NOTE:
                 // 更新所有匹配条件的便签
                 selection = "(" + selection + ") AND " + NoteColumns.ID + ">0 ";
                 count = db.delete(TABLE.NOTE, selection, selectionArgs);
+                // 执行删除操作
                 break;
             case URI_NOTE_ITEM:
                 // 更新单个便签
@@ -215,28 +217,30 @@ public class NotesProvider extends ContentProvider {
                 }
                 count = db.delete(TABLE.NOTE,
                         NoteColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
+                // 删除便签表中的记录
                 break;
             case URI_DATA:
                 count = db.delete(TABLE.DATA, selection, selectionArgs);
-                deleteData = true;
+                deleteData = true;// 标记需要删除数据表中的记录
                 break;
             case URI_DATA_ITEM:
                 id = uri.getPathSegments().get(1);
                 count = db.delete(TABLE.DATA,
                         DataColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
-                deleteData = true;
+                // 删除数据表中的记录
+                deleteData = true; // 标记需要删除数据表中的记录
                 break;
             default:
                 throw new IllegalArgumentException("Unknown URI " + uri);
         }
         //通知数据变化
         if (count > 0) {
-            if (deleteData) {
+            if (deleteData) {// 如果删除了数据表中的记录
                 getContext().getContentResolver().notifyChange(Notes.CONTENT_NOTE_URI, null);
             }
             getContext().getContentResolver().notifyChange(uri, null);
         }
-        return count;
+        return count;// 返回删除的记录数
     }
 
     @Override