问题
I want only a single notification after all the bulk insertion is done into database. Please provide an example to use bulkInsert() function. I cannot find a proper example on internet. Please Help!!!!
回答1:
This is bulkInsert using ContentProvider.
public int bulkInsert(Uri uri, ContentValues[] values){
int numInserted = 0;
String table;
int uriType = sURIMatcher.match(uri);
switch (uriType) {
case PEOPLE:
table = TABLE_PEOPLE;
break;
}
SQLiteDatabase sqlDB = database.getWritableDatabase();
sqlDB.beginTransaction();
try {
for (ContentValues cv : values) {
long newID = sqlDB.insertOrThrow(table, null, cv);
if (newID <= 0) {
throw new SQLException("Failed to insert row into " + uri);
}
}
sqlDB.setTransactionSuccessful();
getContext().getContentResolver().notifyChange(uri, null);
numInserted = values.length;
} finally {
sqlDB.endTransaction();
}
return numInserted;
}
Call it only once when you will have more ContentValues in ContentValues[] values array.
回答2:
I searched forever to find a tutorial to implement this on activity side and content provider side. I used "Warlock's" answer from above and it worked great on the content provider side. I used the answer from this post to prepare the ContentValues array on the activity end. I also modified my ContentValues to receive from a string of comma separated values (or new lines, periods, semi colons). Which looked like this:
ContentValues[] bulkToInsert;
List<ContentValues>mValueList = new ArrayList<ContentValues>();
String regexp = "[,;.\\n]+"; // delimiters without space or tab
//String regexp = "[\\s,;.\\n\\t]+"; // delimiters with space and tab
List<String> splitStrings = Arrays.asList(stringToSplit.split(regexp));
for (String temp : splitStrings) {
Log.d("current student name being put: ", temp);
ContentValues mNewValues = new ContentValues();
mNewValues.put(Contract.KEY_STUDENT_NAME, temp );
mNewValues.put(Contract.KEY_GROUP_ID, group_id);
mValueList.add(mNewValues);
}
bulkToInsert = new ContentValues[mValueList.size()];
mValueList.toArray(bulkToInsert);
getActivity().getContentResolver().bulkInsert(Contract.STUDENTS_CONTENT_URI, bulkToInsert);
I couldn't find a cleaner way to attach the delineated split string straight to the ContentValues array for bulkInsert. But this functions until I find it.
回答3:
Try this approach.
public int bulkInsert(@NonNull Uri uri, @NonNull ContentValues[] values) {
final SQLiteDatabase db = mOpenHelper.getWritableDatabase();
switch (sUriMatcher.match(uri)) {
case CODE_WEATHER:
db.beginTransaction();
int rowsInserted = 0;
try {
for (ContentValues value : values) {
long _id = db.insert(WeatherContract.WeatherEntry.TABLE_NAME, null, value);
if (_id != -1) {
rowsInserted++;
}
}
db.setTransactionSuccessful();
} finally {
db.endTransaction();
}
if (rowsInserted > 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return rowsInserted;
default:
return super.bulkInsert(uri, values);
}
}
Warlock's answer inserts either all or none rows. Also, do minimal tasks between setTransactionSuccessful()
and endTransaction()
and of course no database operations between these two function calls.
Code source : Udacity
来源:https://stackoverflow.com/questions/12730908/how-to-use-bulkinsert-function-in-android