我已经寻找了几天的解决方案,不幸的是,我找不到任何适合我的应用程序需要的相关信息。
我要做的是:
调用一个sqLite查询方法
方法查询sqLite表(select所有列)
保存数组中选定的行和列
数组必须返回给调用者
UITableView必须显示返回值
FirstViewController。m:
result = [queryObject myQueryMethod]; //result is of type NSMutableArray
查询。m:
NSString *myUsername;
NSString *from;
NSString *to;
NSString *message;
querySQL = [NSString stringWithFormat:@"SELECT * FROM messages WHERE to = '%@'" , myUsername];
query_stmt = [querySQL UTF8String];
NSMutableArray *allMessages = [[NSMutableArray alloc] init];
if(sqlite3_prepare_v2(_userDB, query_stmt, -1, &statement, NULL) == SQLITE_OK ) {
while (sqlite3_step(statement) == SQLITE_ROW) {
from = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 1)];
to = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)];
message = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 3)];
[allMessages addObject:message]; //MY PROBLEM..
}
return allMessages; //return to caller in FirstViewController.m
}
我的问题是:我怎么能把所有列(三)添加到一个数组,并将数组返回给FirstViewController内的调用者。m为了排序通过索引为UITableView?
要在tableview中显示信息,我使用:
cell.textLabel.text = [result objectAtIndex:indexPath.row];
我将感激任何帮助,我可以得到,谢谢!
要保留所有3列的值,应该使用dictionary。
while (sqlite3_step(statement) == SQLITE_ROW)
{
from = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 1)];
to = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)];
message = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 3)];
NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys: from, @"From", to, @"To", message, @"Message", nil];
[allMessages addObject:dict]; //MY PROBLEM..
}
现在,当获取值时,从字典中获取:
cell.textLabel.text = [[result objectAtIndex:indexPath.row] objectForKey:@"To"];
您只是将消息值添加到数组中。您应该为这三列中的每一列创建一个具有属性的对象,并返回这些对象的数组。
或者,您可以将三个字符串添加到数组中,并根据其位置检索每个值:
cell.textLabel.text = [result objectAtIndex:indexPath.row * 3];
NSString *to = [result objectAtIndex:indexPath.row * 3 + 1];
NSString *message = [result objectAtIndex:indexPath.row * 3 + 2];
当然,您需要将其他值添加到数组中:
[allMessages addObject:from]; //MY PROBLEM..
[allMessages addObject:to];
[allMessages addObject:message];