Multiple pickerviews and retrieving data from Parse - ios

Question

I have 4 pickerview in a view controller and, I need that after 2 of them have been selected with the desired user preference I want the third to retrieve data from Parse based on the user's selection of the other two, any way I can implement this? Now I've each picker view with a tag but I can't implement a PFQuery inside the pickerview methods.
Thank you.
This is what I have, trying to do a custom pickerview but I would like to use the UIPickerView class methods.
#pragma mark - Select Schedule
-(void)selectSchedule:(NSString *)horari :(NSString *)origen :(NSString *)direccio{
PFQuery *queryParada = [PFQuery queryWithClassName:#"EixBusParades"];
[queryParada whereKey:#"Parada" equalTo:origen];
PFQuery *queryHours = [PFQuery queryWithClassName:#"EixBusParades"];
[queryHours whereKey:#"hSetmana" equalTo:horari];
PFQuery *queryDireccio = [PFQuery queryWithClassName:#"EixBusParades"];
[queryDireccio whereKey:#"direccio" equalTo:direccio];
PFQuery *querySchedule = [PFQuery orQueryWithSubqueries:#[queryHours,queryParada,queryDireccio]];
NSArray *objects = [querySchedule findObjects];
NSArray *depHours = [[objects objectAtIndex:0]objectForKey:#"Horaris"];
// Copy each object from the array depHours to the pickerview array in order to show it
/*int i;
int j = 0;
for (i = 0; i < [depHours count]; i++) {
[self.hores objectAtIndex:j] = [depHours objectAtIndex:i];
j++;
}*/
}
- (IBAction)tfButton:(id)sender {
[self.tfHora becomeFirstResponder];
// Retrieve correct hour data from Parse
[self selectSchedule:self.tf.text :self.tfOrigen.text :self.tfDireccio.text];
}
- (void)cancelTouched:(UIBarButtonItem *)sender{
// hide the picker view
[self.tfHora resignFirstResponder];
}
- (void)doneTouched:(UIBarButtonItem *)sender{
// hide the picker view
[self.tfHora resignFirstResponder];
}
Initialitzation of the picker view in viewdidload.
self.tfHora = [[UITextField alloc] initWithFrame:CGRectZero];
[self.view addSubview:self.tfHora];
UIPickerView *pickerHora = [[UIPickerView alloc]initWithFrame:CGRectMake(0, 0, 0, 0)];
pickerHora.showsSelectionIndicator = YES;
pickerHora.dataSource = self; // Server
pickerHora.delegate = self;
self.tfHora.inputView = pickerHora;
UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];
toolBar.barStyle = UIBarStyleBlackOpaque;
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:#selector(doneTouched:)];
UIBarButtonItem *cancelButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:#selector(cancelTouched:)];
// the middle button is to make the Done button align to right
[toolBar setItems:[NSArray arrayWithObjects:cancelButton, [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil], doneButton, nil]];
self.tfHora.inputAccessoryView = toolBar;