| /* | |
| * Copyright (C) 2007 The Android Open Source Project | |
| * | |
| * Licensed under the Apache License, Version 2.0 (the "License"); | |
| * you may not use this file except in compliance with the License. | |
| * You may obtain a copy of the License at | |
| * | |
| * http://www.apache.org/licenses/LICENSE-2.0 | |
| * | |
| * Unless required by applicable law or agreed to in writing, software | |
| * distributed under the License is distributed on an "AS IS" BASIS, | |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| * See the License for the specific language governing permissions and | |
| * limitations under the License. | |
| */ | |
| package com.example.android.notepad; | |
| import com.example.android.notepad.NotePad; | |
| import android.content.ClipDescription; | |
| import android.content.ContentProvider; | |
| import android.content.ContentUris; | |
| import android.content.ContentValues; | |
| import android.content.Context; | |
| import android.content.UriMatcher; | |
| import android.content.ContentProvider.PipeDataWriter; | |
| import android.content.res.AssetFileDescriptor; | |
| import android.content.res.Resources; | |
| import android.database.Cursor; | |
| import android.database.SQLException; | |
| import android.database.sqlite.SQLiteDatabase; | |
| import android.database.sqlite.SQLiteOpenHelper; | |
| import android.database.sqlite.SQLiteQueryBuilder; | |
| import android.net.Uri; | |
| import android.os.Bundle; | |
| import android.os.ParcelFileDescriptor; | |
| import android.provider.LiveFolders; | |
| import android.text.TextUtils; | |
| import android.util.Log; | |
| import java.io.FileNotFoundException; | |
| import java.io.FileOutputStream; | |
| import java.io.IOException; | |
| import java.io.OutputStreamWriter; | |
| import java.io.PrintWriter; | |
| import java.io.UnsupportedEncodingException; | |
| import java.util.HashMap; | |
| /** | |
| * Provides access to a database of notes. Each note has a title, the note | |
| * itself, a creation date and a modified data. | |
| */ | |
| public class NotePadProvider extends ContentProvider implements PipeDataWriter<Cursor> { | |
| // Used for debugging and logging | |
| private static final String TAG = "NotePadProvider"; | |
| /** | |
| * The database that the provider uses as its underlying data store | |
| */ | |
| private static final String DATABASE_NAME = "note_pad.db"; | |
| /** | |
| * The database version | |
| */ | |
| private static final int DATABASE_VERSION = 2; | |
| /** | |
| * A projection map used to select columns from the database | |
| */ | |
| private static HashMap<String, String> sNotesProjectionMap; | |
| /** | |
| * Standard projection for the interesting columns of a normal note. | |
| */ | |
| private static final String[] READ_NOTE_PROJECTION = new String[] { | |
| NotePad.Notes._ID, // Projection position 0, the note's id | |
| NotePad.Notes.COLUMN_NAME_NOTE, // Projection position 1, the note's content | |
| NotePad.Notes.COLUMN_NAME_TITLE, // Projection position 2, the note's title | |
| }; | |
| private static final int READ_NOTE_NOTE_INDEX = 1; | |
| private static final int READ_NOTE_TITLE_INDEX = 2; | |
| /* | |
| * Constants used by the Uri matcher to choose an action based on the pattern | |
| * of the incoming URI | |
| */ | |
| // The incoming URI matches the Notes URI pattern | |
| private static final int NOTES = 1; | |
| // The incoming URI matches the Note ID URI pattern | |
| private static final int NOTE_ID = 2; | |
| /** | |
| * A UriMatcher instance | |
| */ | |
| private static final UriMatcher sUriMatcher; | |
| // Handle to a new DatabaseHelper. | |
| private DatabaseHelper mOpenHelper; | |
| /** | |
| * A block that instantiates and sets static objects | |
| */ | |
| static { | |
| /* | |
| * Creates and initializes the URI matcher | |
| */ | |
| // Create a new instance | |
| sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH); | |
| // Add a pattern that routes URIs terminated with "notes" to a NOTES operation | |
| sUriMatcher.addURI(NotePad.AUTHORITY, "notes", NOTES); | |
| // Add a pattern that routes URIs terminated with "notes" plus an integer | |
| // to a note ID operation | |
| sUriMatcher.addURI(NotePad.AUTHORITY, "notes/#", NOTE_ID); | |
| /* | |
| * Creates and initializes a projection map that returns all columns | |
| */ | |
| // Creates a new projection map instance. The map returns a column name | |
| // given a string. The two are usually equal. | |
| sNotesProjectionMap = new HashMap<String, String>(); | |
| // Maps the string "_ID" to the column name "_ID" | |
| sNotesProjectionMap.put(NotePad.Notes._ID, NotePad.Notes._ID); | |
| // Maps "title" to "title" | |
| sNotesProjectionMap.put(NotePad.Notes.COLUMN_NAME_TITLE, NotePad.Notes.COLUMN_NAME_TITLE); | |
| // Maps "note" to "note" | |
| sNotesProjectionMap.put(NotePad.Notes.COLUMN_NAME_NOTE, NotePad.Notes.COLUMN_NAME_NOTE); | |
| // Maps "created" to "created" | |
| sNotesProjectionMap.put(NotePad.Notes.COLUMN_NAME_CREATE_DATE, | |
| NotePad.Notes.COLUMN_NAME_CREATE_DATE); | |
| // Maps "modified" to "modified" | |
| sNotesProjectionMap.put( | |
| NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE, | |
| NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE); | |
| } | |
| /** | |
| * | |
| * This class helps open, create, and upgrade the database file. Set to package visibility | |
| * for testing purposes. | |
| */ | |
| static class DatabaseHelper extends SQLiteOpenHelper { | |
| DatabaseHelper(Context context) { | |
| // calls the super constructor, requesting the default cursor factory. | |
| super(context, DATABASE_NAME, null, DATABASE_VERSION); | |
| } | |
| /** | |
| * | |
| * Creates the underlying database with table name and column names taken from the | |
| * NotePad class. | |
| */ | |
| @Override | |
| public void onCreate(SQLiteDatabase db) { | |
| db.execSQL("CREATE TABLE " + NotePad.Notes.TABLE_NAME + " (" | |
| + NotePad.Notes._ID + " INTEGER PRIMARY KEY," | |
| + NotePad.Notes.COLUMN_NAME_TITLE + " TEXT," | |
| + NotePad.Notes.COLUMN_NAME_NOTE + " TEXT," | |
| + NotePad.Notes.COLUMN_NAME_CREATE_DATE + " INTEGER," | |
| + NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE + " INTEGER" | |
| + ");"); | |
| } | |
| /** | |
| * | |
| * Demonstrates that the provider must consider what happens when the | |
| * underlying datastore is changed. In this sample, the database is upgraded the database | |
| * by destroying the existing data. | |
| * A real application should upgrade the database in place. | |
| */ | |
| @Override | |
| public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { | |
| // Logs that the database is being upgraded | |
| Log.w(TAG, "Upgrading database from version " + oldVersion + " to " | |
| + newVersion + ", which will destroy all old data"); | |
| // Kills the table and existing data | |
| db.execSQL("DROP TABLE IF EXISTS notes"); | |
| // Recreates the database with a new version | |
| onCreate(db); | |
| } | |
| } | |
| /** | |
| * | |
| * Initializes the provider by creating a new DatabaseHelper. onCreate() is called | |
| * automatically when Android creates the provider in response to a resolver request from a | |
| * client. | |
| */ | |
| @Override | |
| public boolean onCreate() { | |
| // Creates a new helper object. Note that the database itself isn't opened until | |
| // something tries to access it, and it's only created if it doesn't already exist. | |
| mOpenHelper = new DatabaseHelper(getContext()); | |
| // Assumes that any failures will be reported by a thrown exception. | |
| return true; | |
| } | |
| /** | |
| * This method is called when a client calls | |
| * {@link android.content.ContentResolver#query(Uri, String[], String, String[], String)}. | |
| * Queries the database and returns a cursor containing the results. | |
| * | |
| * @return A cursor containing the results of the query. The cursor exists but is empty if | |
| * the query returns no results or an exception occurs. | |
| * @throws IllegalArgumentException if the incoming URI pattern is invalid. | |
| */ | |
| @Override | |
| public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, | |
| String sortOrder) { | |
| // Constructs a new query builder and sets its table name | |
| SQLiteQueryBuilder qb = new SQLiteQueryBuilder(); | |
| qb.setTables(NotePad.Notes.TABLE_NAME); | |
| /** | |
| * Choose the projection and adjust the "where" clause based on URI pattern-matching. | |
| */ | |
| switch (sUriMatcher.match(uri)) { | |
| // If the incoming URI is for notes, chooses the Notes projection | |
| case NOTES: | |
| qb.setProjectionMap(sNotesProjectionMap); | |
| break; | |
| /* If the incoming URI is for a single note identified by its ID, chooses the | |
| * note ID projection, and appends "_ID = <noteID>" to the where clause, so that | |
| * it selects that single note | |
| */ | |
| case NOTE_ID: | |
| qb.setProjectionMap(sNotesProjectionMap); | |
| qb.appendWhere( | |
| NotePad.Notes._ID + // the name of the ID column | |
| "=" + | |
| // the position of the note ID itself in the incoming URI | |
| uri.getPathSegments().get(NotePad.Notes.NOTE_ID_PATH_POSITION)); | |
| break; | |
| default: | |
| // If the URI doesn't match any of the known patterns, throw an exception. | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| String orderBy; | |
| // If no sort order is specified, uses the default | |
| if (TextUtils.isEmpty(sortOrder)) { | |
| orderBy = NotePad.Notes.DEFAULT_SORT_ORDER; | |
| } else { | |
| // otherwise, uses the incoming sort order | |
| orderBy = sortOrder; | |
| } | |
| // Opens the database object in "read" mode, since no writes need to be done. | |
| SQLiteDatabase db = mOpenHelper.getReadableDatabase(); | |
| /* | |
| * Performs the query. If no problems occur trying to read the database, then a Cursor | |
| * object is returned; otherwise, the cursor variable contains null. If no records were | |
| * selected, then the Cursor object is empty, and Cursor.getCount() returns 0. | |
| */ | |
| Cursor c = qb.query( | |
| db, // The database to query | |
| projection, // The columns to return from the query | |
| selection, // The columns for the where clause | |
| selectionArgs, // The values for the where clause | |
| null, // don't group the rows | |
| null, // don't filter by row groups | |
| orderBy // The sort order | |
| ); | |
| // Tells the Cursor what URI to watch, so it knows when its source data changes | |
| c.setNotificationUri(getContext().getContentResolver(), uri); | |
| return c; | |
| } | |
| /** | |
| * This is called when a client calls {@link android.content.ContentResolver#getType(Uri)}. | |
| * Returns the MIME data type of the URI given as a parameter. | |
| * | |
| * @param uri The URI whose MIME type is desired. | |
| * @return The MIME type of the URI. | |
| * @throws IllegalArgumentException if the incoming URI pattern is invalid. | |
| */ | |
| @Override | |
| public String getType(Uri uri) { | |
| /** | |
| * Chooses the MIME type based on the incoming URI pattern | |
| */ | |
| switch (sUriMatcher.match(uri)) { | |
| // If the pattern is for notes or live folders, returns the general content type. | |
| case NOTES: | |
| return NotePad.Notes.CONTENT_TYPE; | |
| // If the pattern is for note IDs, returns the note ID content type. | |
| case NOTE_ID: | |
| return NotePad.Notes.CONTENT_ITEM_TYPE; | |
| // If the URI pattern doesn't match any permitted patterns, throws an exception. | |
| default: | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| } | |
| //BEGIN_INCLUDE(stream) | |
| /** | |
| * This describes the MIME types that are supported for opening a note | |
| * URI as a stream. | |
| */ | |
| static ClipDescription NOTE_STREAM_TYPES = new ClipDescription(null, | |
| new String[] { ClipDescription.MIMETYPE_TEXT_PLAIN }); | |
| /** | |
| * Returns the types of available data streams. URIs to specific notes are supported. | |
| * The application can convert such a note to a plain text stream. | |
| * | |
| * @param uri the URI to analyze | |
| * @param mimeTypeFilter The MIME type to check for. This method only returns a data stream | |
| * type for MIME types that match the filter. Currently, only text/plain MIME types match. | |
| * @return a data stream MIME type. Currently, only text/plan is returned. | |
| * @throws IllegalArgumentException if the URI pattern doesn't match any supported patterns. | |
| */ | |
| @Override | |
| public String[] getStreamTypes(Uri uri, String mimeTypeFilter) { | |
| /** | |
| * Chooses the data stream type based on the incoming URI pattern. | |
| */ | |
| switch (sUriMatcher.match(uri)) { | |
| // If the pattern is for notes or live folders, return null. Data streams are not | |
| // supported for this type of URI. | |
| case NOTES: | |
| return null; | |
| // If the pattern is for note IDs and the MIME filter is text/plain, then return | |
| // text/plain | |
| case NOTE_ID: | |
| return NOTE_STREAM_TYPES.filterMimeTypes(mimeTypeFilter); | |
| // If the URI pattern doesn't match any permitted patterns, throws an exception. | |
| default: | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| } | |
| /** | |
| * Returns a stream of data for each supported stream type. This method does a query on the | |
| * incoming URI, then uses | |
| * {@link android.content.ContentProvider#openPipeHelper(Uri, String, Bundle, Object, | |
| * PipeDataWriter)} to start another thread in which to convert the data into a stream. | |
| * | |
| * @param uri The URI pattern that points to the data stream | |
| * @param mimeTypeFilter A String containing a MIME type. This method tries to get a stream of | |
| * data with this MIME type. | |
| * @param opts Additional options supplied by the caller. Can be interpreted as | |
| * desired by the content provider. | |
| * @return AssetFileDescriptor A handle to the file. | |
| * @throws FileNotFoundException if there is no file associated with the incoming URI. | |
| */ | |
| @Override | |
| public AssetFileDescriptor openTypedAssetFile(Uri uri, String mimeTypeFilter, Bundle opts) | |
| throws FileNotFoundException { | |
| // Checks to see if the MIME type filter matches a supported MIME type. | |
| String[] mimeTypes = getStreamTypes(uri, mimeTypeFilter); | |
| // If the MIME type is supported | |
| if (mimeTypes != null) { | |
| // Retrieves the note for this URI. Uses the query method defined for this provider, | |
| // rather than using the database query method. | |
| Cursor c = query( | |
| uri, // The URI of a note | |
| READ_NOTE_PROJECTION, // Gets a projection containing the note's ID, title, | |
| // and contents | |
| null, // No WHERE clause, get all matching records | |
| null, // Since there is no WHERE clause, no selection criteria | |
| null // Use the default sort order (modification date, | |
| // descending | |
| ); | |
| // If the query fails or the cursor is empty, stop | |
| if (c == null || !c.moveToFirst()) { | |
| // If the cursor is empty, simply close the cursor and return | |
| if (c != null) { | |
| c.close(); | |
| } | |
| // If the cursor is null, throw an exception | |
| throw new FileNotFoundException("Unable to query " + uri); | |
| } | |
| // Start a new thread that pipes the stream data back to the caller. | |
| return new AssetFileDescriptor( | |
| openPipeHelper(uri, mimeTypes[0], opts, c, this), 0, | |
| AssetFileDescriptor.UNKNOWN_LENGTH); | |
| } | |
| // If the MIME type is not supported, return a read-only handle to the file. | |
| return super.openTypedAssetFile(uri, mimeTypeFilter, opts); | |
| } | |
| /** | |
| * Implementation of {@link android.content.ContentProvider.PipeDataWriter} | |
| * to perform the actual work of converting the data in one of cursors to a | |
| * stream of data for the client to read. | |
| */ | |
| @Override | |
| public void writeDataToPipe(ParcelFileDescriptor output, Uri uri, String mimeType, | |
| Bundle opts, Cursor c) { | |
| // We currently only support conversion-to-text from a single note entry, | |
| // so no need for cursor data type checking here. | |
| FileOutputStream fout = new FileOutputStream(output.getFileDescriptor()); | |
| PrintWriter pw = null; | |
| try { | |
| pw = new PrintWriter(new OutputStreamWriter(fout, "UTF-8")); | |
| pw.println(c.getString(READ_NOTE_TITLE_INDEX)); | |
| pw.println(""); | |
| pw.println(c.getString(READ_NOTE_NOTE_INDEX)); | |
| } catch (UnsupportedEncodingException e) { | |
| Log.w(TAG, "Ooops", e); | |
| } finally { | |
| c.close(); | |
| if (pw != null) { | |
| pw.flush(); | |
| } | |
| try { | |
| fout.close(); | |
| } catch (IOException e) { | |
| } | |
| } | |
| } | |
| //END_INCLUDE(stream) | |
| /** | |
| * This is called when a client calls | |
| * {@link android.content.ContentResolver#insert(Uri, ContentValues)}. | |
| * Inserts a new row into the database. This method sets up default values for any | |
| * columns that are not included in the incoming map. | |
| * If rows were inserted, then listeners are notified of the change. | |
| * @return The row ID of the inserted row. | |
| * @throws SQLException if the insertion fails. | |
| */ | |
| @Override | |
| public Uri insert(Uri uri, ContentValues initialValues) { | |
| // Validates the incoming URI. Only the full provider URI is allowed for inserts. | |
| if (sUriMatcher.match(uri) != NOTES) { | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| // A map to hold the new record's values. | |
| ContentValues values; | |
| // If the incoming values map is not null, uses it for the new values. | |
| if (initialValues != null) { | |
| values = new ContentValues(initialValues); | |
| } else { | |
| // Otherwise, create a new value map | |
| values = new ContentValues(); | |
| } | |
| // Gets the current system time in milliseconds | |
| Long now = Long.valueOf(System.currentTimeMillis()); | |
| // If the values map doesn't contain the creation date, sets the value to the current time. | |
| if (values.containsKey(NotePad.Notes.COLUMN_NAME_CREATE_DATE) == false) { | |
| values.put(NotePad.Notes.COLUMN_NAME_CREATE_DATE, now); | |
| } | |
| // If the values map doesn't contain the modification date, sets the value to the current | |
| // time. | |
| if (values.containsKey(NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE) == false) { | |
| values.put(NotePad.Notes.COLUMN_NAME_MODIFICATION_DATE, now); | |
| } | |
| // If the values map doesn't contain a title, sets the value to the default title. | |
| if (values.containsKey(NotePad.Notes.COLUMN_NAME_TITLE) == false) { | |
| Resources r = Resources.getSystem(); | |
| values.put(NotePad.Notes.COLUMN_NAME_TITLE, r.getString(android.R.string.untitled)); | |
| } | |
| // If the values map doesn't contain note text, sets the value to an empty string. | |
| if (values.containsKey(NotePad.Notes.COLUMN_NAME_NOTE) == false) { | |
| values.put(NotePad.Notes.COLUMN_NAME_NOTE, ""); | |
| } | |
| // Opens the database object in "write" mode. | |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); | |
| // Performs the insert and returns the ID of the new note. | |
| long rowId = db.insert( | |
| NotePad.Notes.TABLE_NAME, // The table to insert into. | |
| NotePad.Notes.COLUMN_NAME_NOTE, // A hack, SQLite sets this column value to null | |
| // if values is empty. | |
| values // A map of column names, and the values to insert | |
| // into the columns. | |
| ); | |
| // If the insert succeeded, the row ID exists. | |
| if (rowId > 0) { | |
| // Creates a URI with the note ID pattern and the new row ID appended to it. | |
| Uri noteUri = ContentUris.withAppendedId(NotePad.Notes.CONTENT_ID_URI_BASE, rowId); | |
| // Notifies observers registered against this provider that the data changed. | |
| getContext().getContentResolver().notifyChange(noteUri, null); | |
| return noteUri; | |
| } | |
| // If the insert didn't succeed, then the rowID is <= 0. Throws an exception. | |
| throw new SQLException("Failed to insert row into " + uri); | |
| } | |
| /** | |
| * This is called when a client calls | |
| * {@link android.content.ContentResolver#delete(Uri, String, String[])}. | |
| * Deletes records from the database. If the incoming URI matches the note ID URI pattern, | |
| * this method deletes the one record specified by the ID in the URI. Otherwise, it deletes a | |
| * a set of records. The record or records must also match the input selection criteria | |
| * specified by where and whereArgs. | |
| * | |
| * If rows were deleted, then listeners are notified of the change. | |
| * @return If a "where" clause is used, the number of rows affected is returned, otherwise | |
| * 0 is returned. To delete all rows and get a row count, use "1" as the where clause. | |
| * @throws IllegalArgumentException if the incoming URI pattern is invalid. | |
| */ | |
| @Override | |
| public int delete(Uri uri, String where, String[] whereArgs) { | |
| // Opens the database object in "write" mode. | |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); | |
| String finalWhere; | |
| int count; | |
| // Does the delete based on the incoming URI pattern. | |
| switch (sUriMatcher.match(uri)) { | |
| // If the incoming pattern matches the general pattern for notes, does a delete | |
| // based on the incoming "where" columns and arguments. | |
| case NOTES: | |
| count = db.delete( | |
| NotePad.Notes.TABLE_NAME, // The database table name | |
| where, // The incoming where clause column names | |
| whereArgs // The incoming where clause values | |
| ); | |
| break; | |
| // If the incoming URI matches a single note ID, does the delete based on the | |
| // incoming data, but modifies the where clause to restrict it to the | |
| // particular note ID. | |
| case NOTE_ID: | |
| /* | |
| * Starts a final WHERE clause by restricting it to the | |
| * desired note ID. | |
| */ | |
| finalWhere = | |
| NotePad.Notes._ID + // The ID column name | |
| " = " + // test for equality | |
| uri.getPathSegments(). // the incoming note ID | |
| get(NotePad.Notes.NOTE_ID_PATH_POSITION) | |
| ; | |
| // If there were additional selection criteria, append them to the final | |
| // WHERE clause | |
| if (where != null) { | |
| finalWhere = finalWhere + " AND " + where; | |
| } | |
| // Performs the delete. | |
| count = db.delete( | |
| NotePad.Notes.TABLE_NAME, // The database table name. | |
| finalWhere, // The final WHERE clause | |
| whereArgs // The incoming where clause values. | |
| ); | |
| break; | |
| // If the incoming pattern is invalid, throws an exception. | |
| default: | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| /* Gets a handle to the content resolver object for the current context, and notifies it | |
| * that the incoming URI changed. The object passes this along to the resolver framework, | |
| * and observers that have registered themselves for the provider are notified. | |
| */ | |
| getContext().getContentResolver().notifyChange(uri, null); | |
| // Returns the number of rows deleted. | |
| return count; | |
| } | |
| /** | |
| * This is called when a client calls | |
| * {@link android.content.ContentResolver#update(Uri,ContentValues,String,String[])} | |
| * Updates records in the database. The column names specified by the keys in the values map | |
| * are updated with new data specified by the values in the map. If the incoming URI matches the | |
| * note ID URI pattern, then the method updates the one record specified by the ID in the URI; | |
| * otherwise, it updates a set of records. The record or records must match the input | |
| * selection criteria specified by where and whereArgs. | |
| * If rows were updated, then listeners are notified of the change. | |
| * | |
| * @param uri The URI pattern to match and update. | |
| * @param values A map of column names (keys) and new values (values). | |
| * @param where An SQL "WHERE" clause that selects records based on their column values. If this | |
| * is null, then all records that match the URI pattern are selected. | |
| * @param whereArgs An array of selection criteria. If the "where" param contains value | |
| * placeholders ("?"), then each placeholder is replaced by the corresponding element in the | |
| * array. | |
| * @return The number of rows updated. | |
| * @throws IllegalArgumentException if the incoming URI pattern is invalid. | |
| */ | |
| @Override | |
| public int update(Uri uri, ContentValues values, String where, String[] whereArgs) { | |
| // Opens the database object in "write" mode. | |
| SQLiteDatabase db = mOpenHelper.getWritableDatabase(); | |
| int count; | |
| String finalWhere; | |
| // Does the update based on the incoming URI pattern | |
| switch (sUriMatcher.match(uri)) { | |
| // If the incoming URI matches the general notes pattern, does the update based on | |
| // the incoming data. | |
| case NOTES: | |
| // Does the update and returns the number of rows updated. | |
| count = db.update( | |
| NotePad.Notes.TABLE_NAME, // The database table name. | |
| values, // A map of column names and new values to use. | |
| where, // The where clause column names. | |
| whereArgs // The where clause column values to select on. | |
| ); | |
| break; | |
| // If the incoming URI matches a single note ID, does the update based on the incoming | |
| // data, but modifies the where clause to restrict it to the particular note ID. | |
| case NOTE_ID: | |
| // From the incoming URI, get the note ID | |
| String noteId = uri.getPathSegments().get(NotePad.Notes.NOTE_ID_PATH_POSITION); | |
| /* | |
| * Starts creating the final WHERE clause by restricting it to the incoming | |
| * note ID. | |
| */ | |
| finalWhere = | |
| NotePad.Notes._ID + // The ID column name | |
| " = " + // test for equality | |
| uri.getPathSegments(). // the incoming note ID | |
| get(NotePad.Notes.NOTE_ID_PATH_POSITION) | |
| ; | |
| // If there were additional selection criteria, append them to the final WHERE | |
| // clause | |
| if (where !=null) { | |
| finalWhere = finalWhere + " AND " + where; | |
| } | |
| // Does the update and returns the number of rows updated. | |
| count = db.update( | |
| NotePad.Notes.TABLE_NAME, // The database table name. | |
| values, // A map of column names and new values to use. | |
| finalWhere, // The final WHERE clause to use | |
| // placeholders for whereArgs | |
| whereArgs // The where clause column values to select on, or | |
| // null if the values are in the where argument. | |
| ); | |
| break; | |
| // If the incoming pattern is invalid, throws an exception. | |
| default: | |
| throw new IllegalArgumentException("Unknown URI " + uri); | |
| } | |
| /* Gets a handle to the content resolver object for the current context, and notifies it | |
| * that the incoming URI changed. The object passes this along to the resolver framework, | |
| * and observers that have registered themselves for the provider are notified. | |
| */ | |
| getContext().getContentResolver().notifyChange(uri, null); | |
| // Returns the number of rows updated. | |
| return count; | |
| } | |
| /** | |
| * A test package can call this to get a handle to the database underlying NotePadProvider, | |
| * so it can insert test data into the database. The test case class is responsible for | |
| * instantiating the provider in a test context; {@link android.test.ProviderTestCase2} does | |
| * this during the call to setUp() | |
| * | |
| * @return a handle to the database helper object for the provider's data. | |
| */ | |
| DatabaseHelper getOpenHelperForTest() { | |
| return mOpenHelper; | |
| } | |
| } |