从表和sqlite数据库中删除行

时间:2011-09-04 10:13:53

标签: iphone objective-c database sqlite

我在从数据库和表中删除行时遇到一些问题。

问题是:我可以滑动该行,点击“删除”按钮,但没有任何反应。

可能我做错了。

有人可以给我一个提示吗? 如果你想看一下这里有所有程序:(更新)

http://cl.ly/9q7U

-(void)tableView:(UITableView *)_tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

    if (editingStyle == UITableViewCellEditingStyleDelete) {

    NSDictionary *rowVals = (NSDictionary *) [shoppingListItems objectAtIndex:indexPath.row];
    NSString *keyValue = (NSString *) [rowVals objectForKey:@"key"];

    [_tableView beginUpdates];
    [_tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
    //Here i got the SIGABRT error
    [_tableView endUpdates];

    sqlite3 *db;
    int dbrc; //Codice di ritorno del database (database return code)
    DatabaseShoppingListAppDelegate *appDelegate = (DatabaseShoppingListAppDelegate*) [UIApplication sharedApplication].delegate;
    const char *dbFilePathUTF8 = [appDelegate.dbFilePath UTF8String];
    dbrc = sqlite3_open(dbFilePathUTF8, &db);
    if (dbrc) {
        NSLog(@"Impossibile aprire il Database!");
        return;
    }

    sqlite3_stmt *dbps; //Istruzione di preparazione del database

    NSString *deleteStatementsNS = [NSString stringWithFormat: @"DELETE FROM \"shoppinglist\" WHERE key='%@'", keyValue];

    const char *deleteStatement = [deleteStatementsNS UTF8String];
    dbrc = sqlite3_prepare_v2(db, deleteStatement, -1, &dbps, NULL);
    dbrc = sqlite3_step(dbps);


    //faccio pulizia rilasciando i database
    sqlite3_finalize(dbps);
    sqlite3_close(db);

}
}

感谢Akshay,最后我修复了这部分代码。我在这里写下了那些需要它的解决方案。

-(void)tableView:(UITableView *)_tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

if (editingStyle == UITableViewCellEditingStyleDelete) {

    NSDictionary *rowVals = (NSDictionary *) [shoppingListItems objectAtIndex:indexPath.row];
    NSString *keyValue = (NSString *) [rowVals objectForKey:@"key"];

    [tableView beginUpdates];

    sqlite3 *db;
    int dbrc; //Codice di ritorno del database (database return code)
    DatabaseShoppingListAppDelegate *appDelegate = (DatabaseShoppingListAppDelegate*) [UIApplication sharedApplication].delegate;
    const char *dbFilePathUTF8 = [appDelegate.dbFilePath UTF8String];
    dbrc = sqlite3_open(dbFilePathUTF8, &db);
    if (dbrc) {
        NSLog(@"Impossibile aprire il Database!");
        return;
    }

    sqlite3_stmt *dbps; //Istruzione di preparazione del database

    NSString *deleteStatementsNS = [NSString stringWithFormat: @"DELETE FROM \"shoppinglist\" WHERE key='%@'", keyValue];

    const char *deleteStatement = [deleteStatementsNS UTF8String];
    dbrc = sqlite3_prepare_v2(db, deleteStatement, -1, &dbps, NULL);
    dbrc = sqlite3_step(dbps);


    //faccio pulizia rilasciando i database
    sqlite3_finalize(dbps);
    sqlite3_close(db);

    [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
    [shoppingListItems removeObjectAtIndex:indexPath.row];

    [tableView endUpdates];

    [tableView reloadData];
}
}

2 个答案:

答案 0 :(得分:2)

你应该打电话:

[tableView beginUpdates];
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]
        withRowAnimation:UITableViewRowAnimationFade];
[tableView endUpdates];

commitEditingStyle:内而不是reloadData。另外,请确保从DB&中删除实体。从numberOfRowsInSection:返回少一个。

答案 1 :(得分:1)

我认为问题出在这一行

NSString *insertStatementsNS = [NSString stringWithFormat: @"DELETE FROM \"shoppinglist\" WHERE key=?", indexPath];

我想你想进入insertStatementsNS这个:

NSString *insertStatementsNS = [NSString stringWithFormat: @"DELETE FROM \"shoppinglist\" WHERE key=%@", indexPath];

NSString *insertStatementsNS = [NSString stringWithFormat: @"DELETE FROM \"shoppinglist\" WHERE key='%@'", indexPath];