call an array method - objective-c

Question

I have this method, and I am trying to call that method doing [self getUsers ObjectAtIndex:0] but compiler won't compile that line at all and says it's unknown. How do I call an array method to display all the string in it?
- (NSArray*)getUsers
{
NSArray *getUsers = [[NSArray alloc] init];
NSString *databasepath;
NSString *docsDir;
NSArray *dirPaths;
//NSString *databasePath;
//get the document directory
dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
docsDir = [dirPaths objectAtIndex:0];
//build the path to the database file
databasepath = [[NSString alloc] initWithString: [docsDir stringByAppendingPathComponent:
#"users.db"]];
const char *dbPath = [databasepath UTF8String];
sqlite3_stmt *statement;
sqlite3 *userdb;
if (sqlite3_open(dbPath, &userdb) == SQLITE_OK)
{
NSString *querySQL = [NSString stringWithFormat:#"SELECT * FROM USERS WHERE username = \"%#\"", txtUsername.text];
const char *sql_stmt = [querySQL UTF8String];
if (sqlite3_prepare_v2(userdb, sql_stmt, -1, &statement, NULL) == SQLITE_OK)
{
while (sqlite3_step(statement) == SQLITE_ROW)
{
char *field = (char*) sqlite3_column_text(statement, 1);
NSString *usernameField = [[NSString alloc]initWithUTF8String:field];
//NSLog(#"%#", usernameField);
getUsers = [NSArray arrayWithObject:usernameField];
}
}
sqlite3_finalize(statement);
}
sqlite3_close(userdb);
return getUsers;
}

Answer 1

Use [[self getUsers] objectAtIndex:0].
If you use the latest Xcode/clang version, you can also use [self getUsers][0], since arrays now support indexing.

Answer 2

Consider say you had a method -(id)someMethod, and then called it like this:
id myValue = [self someMethod];
Inside someMethod, there is a return statement - whatever is to the right of the return is what will be assigned to myValue in the calling method or function.
Just call like this:
NSArray *arrAllUsers = [self getUsers]; //As getUsers is method which returns nsarray.