【发布时间】：2016-08-28 20:26:58
【问题描述】：
我是初学者，这个主题对我来说很难理解。任何代码帮助将不胜感激。
主 UITableView 包含来自本地 JSON 文件的所有配方对象。
第二个 UITableView 包含 JSON 文件中每个配方的所有成分值，用户可以在其中选择成分。在第二个表格视图中，我使用了 replaceOccurrencesOfString 来缩短成分字符串，例如，从 1/2 汤匙盐 到 盐。选定的成分存储在 NSUserDefaults 中。
我需要能够过滤显示在主 tableview 上的食谱，以仅显示那些包含用户在第二个 tableview 中选择的成分的食谱。由于在第二个表视图中使用了 replaceOccurrencesOfString，存储在 NSUserDefaults 中的成分不能与 JSON 文件中的成分完全匹配。
有人对如何做到这一点有任何建议吗？我什至不知道从哪里开始。
本地 JSON 文件：
{
"locations": [
{ "name" : "Drop Biscuits and Sausage Gravy", "ingredients" : "Biscuits\n3 cups All-purpose Flour\n2 Tablespoons Baking Powder\n1/2 teaspoon Salt\nShortened for example”, "cookTime" : "PT30M" },
{ "name" : "Hot Roast Beef Sandwiches", "ingredients" : "12 whole Dinner Rolls Or Small Sandwich Buns (I Used Whole Wheat)\n1 pound Thinly Shaved Roast Beef Or Ham (or Both!)\nShortened for example”, "cookTime" : "PT30M" },
//many more records. only included 2 for example
]
}
主表视图 - 所有食谱都在 UITableView 中返回，如下所示：
@interface LocationsViewController () <UISearchResultsUpdating>
@property (nonatomic, strong) NSArray *RecipeArray;
@property (nonatomic, strong) UISearchController *searchController;
@property (nonatomic, strong) NSMutableArray *searchResults;
@property (nonatomic, strong) NSArray *RecipeByIngredientsArray;
@end
@implementation LocationsViewController {
NSArray *_locations;
}
- (void)viewDidLoad {
[super viewDidLoad];
initWithTitle:(@"Kitchen") style:(UIBarButtonItemStylePlain) target:(self) action:(@selector(FilterButton:))];
// Create a new JSONLoader with a local file URL
JSONLoader *jsonLoader = [[JSONLoader alloc] init];
NSURL *url = [[NSBundle mainBundle] URLForResource:@"locations" withExtension:@"json"];
instantiateViewControllerWithIdentifier: method
UINavigationController *searchResultsController = [[self storyboard] instantiateViewControllerWithIdentifier:@"LocationsViewSearchResultsNavController"];
// Our instance of UISearchController will use searchResults
self.searchController = [[UISearchController alloc] initWithSearchResultsController:searchResultsController];
self.searchController.searchResultsUpdater = self;
self.searchController.searchBar.frame = CGRectMake(self.searchController.searchBar.frame.origin.x,
self.searchController.searchBar.frame.origin.y,
self.searchController.searchBar.frame.size.width, 44.0);
self.tableView.tableHeaderView = self.searchController.searchBar;
self.definesPresentationContext = true;
// Load the data on a background queue...
// As we are using a local file it's not really necessary, but if we were connecting to an online URL then we'd need it
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
self.RecipeArray = [jsonLoader locationsFromJSONFile:url];
// Now that we have the data, reload the table data on the main UI thread
[self.tableView performSelectorOnMainThread:@selector(reloadData) withObject:nil waitUntilDone:YES];
});
}
// Just before showing the LocationDetailViewController, set the selected Location object
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
LocationDetailViewController *vc = segue.destinationViewController;
NSIndexPath *indexPath = [self.tableView indexPathForCell:sender];
vc.location = [self.RecipeArray objectAtIndex:indexPath.row];
//self.searchController.active = false;
}
-(void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
NSInteger tag = 120;
cell.contentView.backgroundColor = [UIColor colorWithRed:239/255.0 green:239/255.0 blue:244/255.0 alpha:1.0];
UIView *whiteRoundedView = [[UIView alloc]initWithFrame:CGRectMake(6, 5, self.view.frame.size.width-12, cell.contentView.frame.size.height-15)];
CGFloat colors[]={1.0,1.0,1.0,1.0};//cell color white
whiteRoundedView.layer.backgroundColor = CGColorCreate(CGColorSpaceCreateDeviceRGB(), colors);
whiteRoundedView.layer.masksToBounds = false;
whiteRoundedView.layer.cornerRadius = 3.0;
whiteRoundedView.layer.shadowOffset = CGSizeMake(-1, 1);
whiteRoundedView.layer.shadowOpacity = 0.2;
{if (cell.tag !=120) {cell.contentView.backgroundColor = [UIColor clearColor];
[cell.contentView addSubview:whiteRoundedView];
[cell.contentView sendSubviewToBack:whiteRoundedView];
cell.tag = tag;}}
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
#pragma mark - Table View Controller Methods
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"LocationCell"];
Location *location = [self.RecipeArray objectAtIndex:indexPath.row];
//*****recall NSUserDefaults works, but not sure how to compare*******
NSMutableArray* array1 = [[NSUserDefaults standardUserDefaults] objectForKey:@"selections"];
NSLog(@"-----------selections-----------%@", array1);
cell.textLabel.text = location.name;
cell.detailTextLabel.text = location.cookTime;
cell.imageView.image = [UIImage imageNamed:@"recipeicon2.png"];
return cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return 100;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [self.RecipeArray count];
}
}
@end
第二个表格视图：
@interface FilterViewController () <UISearchResultsUpdating>
@property (nonatomic, strong) NSArray *IngredientsArray;
@property (nonatomic, strong) UISearchController *searchController;
@property (nonatomic, strong) NSMutableArray *searchResults;
@property (nonatomic, strong) NSMutableSet *selectedRowObjects;
@property (nonatomic, strong) NSMutableDictionary *selectedRows;
@property (nonatomic, strong) NSMutableArray *selections;
@end
@implementation FilterViewController {
NSArray *_locations;
}
- (void)viewDidLoad {
[super viewDidLoad];
//self.selections = [NSMutableArray array];
self.selections = [NSMutableArray arrayWithArray:(NSArray *)[[NSUserDefaults standardUserDefaults] objectForKey:@"selections"]];
if(self.selections == nil){
self.selections = [[NSMutableArray alloc] init];
}
//_myMtableArray = [[NSMutableArray alloc] init];
// Create a new JSONLoader with a local file URL
JSONLoaderIngreds *jsonLoader = [[JSONLoaderIngreds alloc] init];
NSURL *url = [[NSBundle mainBundle] URLForResource:@"locations" withExtension:@"json"];
// There's no transition in our storyboard to our search results tableview or navigation controller
// so we'll have to grab it using the instantiateViewControllerWithIdentifier: method
UINavigationController *searchResultsController = [[self storyboard] instantiateViewControllerWithIdentifier:@"FilterViewSearchResultsNavController"];
// Our instance of UISearchController will use searchResults
self.searchController = [[UISearchController alloc] initWithSearchResultsController:searchResultsController];
// The searchcontroller's searchResultsUpdater property will contain our tableView.
self.searchController.searchResultsUpdater = self;
self.searchController.searchBar.frame = CGRectMake(self.searchController.searchBar.frame.origin.x,
self.searchController.searchBar.frame.origin.y,
self.searchController.searchBar.frame.size.width, 44.0);
self.tableView.tableHeaderView = self.searchController.searchBar;
self.definesPresentationContext = true;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
_locations = [jsonLoader ingredientsFromJSONFile:url];
// Now that we have the data, reload the table data on the main UI thread
[self.tableView performSelectorOnMainThread:@selector(reloadData) withObject:nil waitUntilDone:YES];
});
_selectedRows = [[NSMutableDictionary alloc] init];
}
// Just before showing the LocationViewController, set the selected Location object
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
LocationsViewController *vc = segue.destinationViewController;
NSIndexPath *indexPath = [self.tableView indexPathForCell:sender];
vc.location = [_locations objectAtIndex:indexPath.row];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
#pragma mark - Table View Controller Methods
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
[tableView deselectRowAtIndexPath:indexPath animated:YES];
//the below code will allow multiple selection
if ([self.selections containsObject:cell.textLabel.text])
{
[self.selections removeObject:cell.textLabel.text];
}
else
{
[self.selections addObject:cell.textLabel.text];
}
[tableView reloadData];
NSLog(@"***************Selected Ingredients**************** %@", _selections);
NSUserDefaults *userdefaults = [NSUserDefaults standardUserDefaults];
[userdefaults setObject:_selections forKey:@"selections"];
[userdefaults synchronize];
NSLog(@"-------------NSUserDefaults------------%@", [[NSUserDefaults standardUserDefaults] dictionaryRepresentation]);
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"FilterCell"];
cell.textLabel.text = [_locations objectAtIndex:indexPath.row];
cell.imageView.image = [UIImage imageNamed:@"ingredientsicon3232.png"];
if ([self.selections containsObject:cell.textLabel.text])
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
return cell;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [_locations count];
}
@end
【问题讨论】：
标签： ios objective-c arrays json uitableview