adding parse search feature with PFQueryTableViewController

Question

I am trying to implement a search feature that searches data in remote locations like parse.com using PFQueryTableViewController. So far, I got the local data to be searched successfully but need help adding in remote data sources. Here is my code so far.

//
//  CustomTableViewController.m
//  CustomTable
//
//  Created by Simon on 7/12/13.
//  Copyright (c) 2013 Appcoda. All rights reserved.
//

#import "RecipeTableViewController.h"
#import "RecipeTableCell.h"
#import "RecipeDetailViewController.h"
#import "Recipe.h"

@interface RecipeTableViewController ()

@end

@implementation RecipeTableViewController
{
    NSArray *recipes;
    NSArray *searchResults;
}


- (void)viewDidLoad
{
    [super viewDidLoad];

    // Initialize the recipes array
    Recipe *recipe1 = [Recipe new];
    recipe1.name = @"Egg Benedict";
    recipe1.prepTime = @"30 min";
    recipe1.image = @"egg_benedict.jpg";
    recipe1.ingredients = [NSArray arrayWithObjects:@"2 fresh English muffins", @"4 eggs", @"4 rashers of back bacon", @"2 egg yolks", @"1 tbsp of lemon juice", @"125 g of butter", @"salt and pepper", nil];

    Recipe *recipe2 = [Recipe new];
    recipe2.name = @"Mushroom Risotto";
    recipe2.prepTime = @"30 min";
    recipe2.image = @"mushroom_risotto.jpg";
    recipe2.ingredients = [NSArray arrayWithObjects:@"1 tbsp dried porcini mushrooms", @"2 tbsp olive oil", @"1 onion, chopped", @"2 garlic cloves", @"350g/12oz arborio rice", @"1.2 litres/2 pints hot vegetable stock", @"salt and pepper", @"25g/1oz butter", nil];

    Recipe *recipe3 = [Recipe new];
    recipe3.name = @"Full Breakfast";
    recipe3.prepTime = @"20 min";
    recipe3.image = @"full_breakfast.jpg";
    recipe3.ingredients = [NSArray arrayWithObjects:@"2 sausages", @"100 grams of mushrooms", @"2 rashers of bacon", @"2 eggs", @"150 grams of baked beans", @"Vegetable oil", nil];

    Recipe *recipe4 = [Recipe new];
    recipe4.name = @"Hamburger";
    recipe4.prepTime = @"30 min";
    recipe4.image = @"hamburger.jpg";
    recipe4.ingredients = [NSArray arrayWithObjects:@"400g of ground beef", @"1/4 onion (minced)", @"1 tbsp butter", @"hamburger bun", @"1 teaspoon dry mustard", @"Salt and pepper", nil];

    Recipe *recipe5 = [Recipe new];
    recipe5.name = @"Ham and Egg Sandwich";
    recipe5.prepTime = @"10 min";
    recipe5.image = @"ham_and_egg_sandwich.jpg";
    recipe5.ingredients = [NSArray arrayWithObjects:@"1 unsliced loaf (1 pound) French bread", @"4 tablespoons butter", @"2 tablespoons mayonnaise", @"8 thin slices deli ham", @"1 large tomato, sliced", @"1 small onion", @"8 eggs", @"8 slices cheddar cheese", nil];

    Recipe *recipe6 = [Recipe new];
    recipe6.name = @"Creme Brelee";
    recipe6.prepTime = @"1 hour";
    recipe6.image = @"creme_brelee.jpg";
    recipe6.ingredients = [NSArray arrayWithObjects:@"1 quart heavy cream", @"1 vanilla bean, split and scraped", @"1 cup vanilla sugar", @"6 large egg yolks", @"2 quarts hot water", nil];

    Recipe *recipe7 = [Recipe new];
    recipe7.name = @"White Chocolate Donut";
    recipe7.prepTime = @"45 min";
    recipe7.image = @"white_chocolate_donut.jpg";
    recipe7.ingredients = [NSArray arrayWithObjects:@"3 1/4 cups flour", @"2 teaspoons baking powder", @"1/4 teaspoon salt", @"2 beaten eggs", @"2/3 cup sugar", @"2 ounces melted white chocolate", @"1/2 cup milk", nil];

    Recipe *recipe8 = [Recipe new];
    recipe8.name = @"Starbucks Coffee";
    recipe8.prepTime = @"5 min";
    recipe8.image = @"starbucks_coffee.jpg";
    recipe8.ingredients = [NSArray arrayWithObjects:@"2/3 cup whole milk", @"6 tablespoons white chocolate chips", @"coffee", @"whipped cream", nil];

    Recipe *recipe9 = [Recipe new];
    recipe9.name = @"Vegetable Curry";
    recipe9.prepTime = @"30 min";
    recipe9.image = @"vegetable_curry.jpg";
    recipe9.ingredients = [NSArray arrayWithObjects:@"1 tablespoon olive oil", @"1 onion, chopped", @"2 cloves garlic", @"2 1/2 tablespoons curry powder", @"2 quarts hot water", nil];

    Recipe *recipe10 = [Recipe new];
    recipe10.name = @"Instant Noodle with Egg";
    recipe10.prepTime = @"8 min";
    recipe10.image = @"instant_noodle_with_egg.jpg";
    recipe10.ingredients = [NSArray arrayWithObjects:@"1 pack of Instant Noodle", @"2 eggs", nil];

    Recipe *recipe11 = [Recipe new];
    recipe11.name = @"Noodle with BBQ Pork";
    recipe11.prepTime = @"20 min";
    recipe11.image = @"noodle_with_bbq_pork.jpg";
    recipe11.ingredients = [NSArray arrayWithObjects:@"1 pack of Instant Noodle", @"BBQ pork", @"Salt and Pepper", nil];

    Recipe *recipe12 = [Recipe new];
    recipe12.name = @"Japanese Noodle with Pork";
    recipe12.prepTime = @"20 min";
    recipe12.image = @"japanese_noodle_with_pork.jpg";
    recipe12.ingredients = [NSArray arrayWithObjects:@"1 pack of Japanese Noodle", @"2 green onions", @"2 garlic cloves, minced", @"4 boneless pork loin chops", nil];

    Recipe *recipe13 = [Recipe new];
    recipe13.name = @"Green Tea";
    recipe13.prepTime = @"5 min";
    recipe13.image = @"green_tea.jpg";
    recipe13.ingredients = [NSArray arrayWithObjects:@"Green tea", nil];

    Recipe *recipe14 = [Recipe new];
    recipe14.name = @"Thai Shrimp Cake";
    recipe14.prepTime = @"1.5 hours";
    recipe14.image = @"thai_shrimp_cake.jpg";
    recipe14.ingredients = [NSArray arrayWithObjects:@"8 oz (250g) peeled and deveined raw shrimp", @"2 tablespoons red curry paste", @"1 large egg", @"2 teaspoon fish sauce", @"1 tablespoon sugar", @"2 tablespoons coconut milk", @"2 tablespoons roughly chopped Thai basil leaves", nil];

    Recipe *recipe15 = [Recipe new];
    recipe15.name = @"Angry Birds Cake";
    recipe15.prepTime = @"4 hours";
    recipe15.image = @"angry_birds_cake.jpg";
    recipe15.ingredients = [NSArray arrayWithObjects:@"12 tablespoons (1 1/2 sticks) unsalted butter", @"2 1/2 cups all-purpose flour", @"1 tablespoon baking powder", @"1 teaspoon salt", @"1 3/4 cups sugar", @"2 large eggs, plus 3 large egg yolks", @"1 cup of milk", nil];

    Recipe *recipe16 = [Recipe new];
    recipe16.name = @"Ham and Cheese Panini";
    recipe16.prepTime = @"10 min";
    recipe16.image = @"ham_and_cheese_panini.jpg";
    recipe16.ingredients = [NSArray arrayWithObjects:@"2 tablespoons unsalted butter", @"4 cups thinly sliced shallots", @"2 teaspoons fresh thyme", @"1/4 cup grainy Dijon mustard", @"8 slices rustic white bread", @"8 slices Gruyere cheese", @"8 ounces sliced cooked ham", nil];

    recipes = [NSArray arrayWithObjects:recipe1, recipe2, recipe3, recipe4, recipe5, recipe6, recipe7, recipe8, recipe9, recipe10, recipe11, recipe12, recipe13, recipe14, recipe15, recipe16, nil];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if (tableView == self.searchDisplayController.searchResultsTableView) {
        return [searchResults count];

    } else {
        return [recipes count];
    }
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 71;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"CustomTableCell";
    RecipeTableCell *cell = (RecipeTableCell *)[self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    // Configure the cell...
    if (cell == nil) {
        cell = [[RecipeTableCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    // Display recipe in the table cell
    Recipe *recipe = nil;
    if (tableView == self.searchDisplayController.searchResultsTableView) {
        recipe = [searchResults objectAtIndex:indexPath.row];
    } else {
        recipe = [recipes objectAtIndex:indexPath.row];
    }

    cell.nameLabel.text = recipe.name;
    cell.thumbnailImageView.image = [UIImage imageNamed:recipe.image];
    cell.prepTimeLabel.text = recipe.prepTime;

    return cell;
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"showRecipeDetail"]) {
        NSIndexPath *indexPath = nil;
        Recipe *recipe = nil;

        if (self.searchDisplayController.active) {
            indexPath = [self.searchDisplayController.searchResultsTableView indexPathForSelectedRow];
            recipe = [searchResults objectAtIndex:indexPath.row];
        } else {
            indexPath = [self.tableView indexPathForSelectedRow];
            recipe = [recipes objectAtIndex:indexPath.row];
        }

        RecipeDetailViewController *destViewController = segue.destinationViewController;
        destViewController.recipe = recipe;
    }
}

- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope
{
    NSPredicate *resultPredicate = [NSPredicate predicateWithFormat:@"name contains[c] %@", searchText];
    searchResults = [recipes filteredArrayUsingPredicate:resultPredicate];
}

-(BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
    [self filterContentForSearchText:searchString
                               scope:[[self.searchDisplayController.searchBar scopeButtonTitles]
                                      objectAtIndex:[self.searchDisplayController.searchBar
                                                     selectedScopeButtonIndex]]];

    return YES;
}


@end

Answer 1

If you want to use PFQueryTableVC, you must override - (PFQuery *)queryForTable and return a query that selects objects from your cloud data. Also, your datasource methods must refer to self.objects as the model (not self.recipes).

An alternative design is to bypass PFQueryTableVC and even UITableVC altogether and just create a UIViewController, give it a UITableView subview, connect that with an outlet, and connect its datasource to the view controller. Continue to maintain an array of recipes as the model, but initialize it on viewDidAppear. In that method,query parse.com, and set recipes equal to the resulting array of PFObjects, then reload the table view.