多个赛段之间不传递对象数据
我已经开始了一个项目，最初完成遵循Appcoda的教程关于使用视图控制器在场景之间传递数据（在这里find它： http : //www.appcoda.com/storyboards-ios-tutorial-pass-data-between-view- controller-with-segue / ）
基本上来自第一个场景的表格数据，而segue连接到另一个显示配方图像，准备时间和配料的控制器。 不过，我想更进一步，并添加另一个视图控制器，将显示如何准备食谱的说明。 所以到目前为止运行是：
初始视图控制器（表格数据） – > recipeDetailViewController – > instructionsViewContoller
所以真的只有三个视图控制器，但都共享相同的数据。 我想在视图控制器之间共享的数据是配方数据，格式如下：
Recipe *recipe1 = [Recipe new]; recipe1.name = @"Egg Benedict"; recipe1.prepTime = @"30 min"; recipe1.imageFile = @"egg_benedictl.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]; recipe1.instructions = @"This is recipe one's instruction set"; 当然这个相关的代码：
self.title = recipe.name; self.prepTimeLabel.text = recipe.prepTime; self.recipePhoto.image = [UIImage imageNamed:recipe.imageFile]; NSMutableString *ingredientText = [NSMutableString string]; for (NSString* ingredient in recipe.ingredients) { [ingredientText appendFormat:@"%@\n", ingredient]; } self.ingredientTextView.text = ingredientText; self.instructionTextView.text = recipe.instructions; recipeLabel.text = recipeName;
但是，当我尝试tp传递给我的第三个视图控制器的说明得到混合的结果。 无论什么都没有通过，拉丁文textField占位符通过，或者只有第一个配方recipe.instruction得到所有食谱通过，无论select什么。 我已经在这一个星期了，现在是时候要求希望了。
如果任何人有任何build议如何在多个赛段之间传递我的食谱数据，我将不胜感激。 我已经把所有的代码粘贴在下面的顶层文件中：
// // minuteMealsViewController.h // minuteMeals // // Created by KMO on 8/18/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import <UIKit/UIKit.h> #import "Recipe.h" @interface minuteMealsViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> @property (nonatomic, strong) IBOutlet UITableView *tableView; //@property (nonatomic, weak) IBOutlet UIImageView *thumbnailImageView; @end
// // minuteMealsViewController.m // minuteMeals // // Created by KMO on 8/18/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import "minuteMealsViewController.h" #import "minuteMealsDetailViewController.h" #import "Recipe.h" @interface minuteMealsViewController () @end @implementation minuteMealsViewController { NSArray *recipes; NSArray *thumbnails; NSArray *recipeTitle; } @synthesize tableView; //@synthesize thumbnailImageView; - (void)viewDidLoad { [super viewDidLoad]; // Initialize table data Recipe *recipe1 = [Recipe new]; recipe1.name = @"Egg Benedict"; recipe1.prepTime = @"30 min"; recipe1.imageFile = @"egg_benedictl.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]; recipe1.instructions = @"This is recipe one's instruction set"; Recipe *recipe2 = [Recipe new]; recipe2.name = @"Mushroom Risotto"; recipe2.prepTime = @"30 min"; recipe2.imageFile = @"mushroom_risottol.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]; recipe2.instructions = @"This is recipe two's instruction set"; Recipe *recipe3 = [Recipe new]; recipe3.name = @"Full Breakfast"; recipe3.prepTime = @"20 min"; recipe3.imageFile = @"full_breakfastl.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.imageFile = @"hamburgerl.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.imageFile = @"ham_and_egg_sandwichl.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.imageFile = @"creme_breleel.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.imageFile = @"white_chocolate_donutl.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 = @"White Chocolate Mocha"; recipe8.prepTime = @"5 min"; recipe8.imageFile = @"starbucks_coffeel.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.imageFile = @"vegetable_curryl.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.imageFile = @"instant_noodle_with_eggl.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.imageFile = @"noodle_with_bbq_porkl.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.imageFile = @"japanese_noodle_with_porkl.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.imageFile = @"green_teal.jpg"; recipe13.ingredients = [NSArray arrayWithObjects:@"Green tea", nil]; Recipe *recipe14 = [Recipe new]; recipe14.name = @"Thai Shrimp Cake"; recipe14.prepTime = @"1.5 hours"; recipe14.imageFile = @"thai_shrimp_cakel.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.imageFile = @"angry_birds_cakel.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.imageFile = @"ham_and_cheese_paninil.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]; recipeTitle = [NSArray arrayWithObjects:@"Egg Benedict", @"Mushroom Risotto", @"Full Breakfast", @"Hamburger", @"Ham and Egg Sandwich", @"Creme Brelee", @"White Chocolate Donut", @"Starbucks Coffee", @"Vegetable Curry", @"Instant Noodle with Egg", @"Noodle with BBQ Pork", @"Japanese Noodle with Pork", @"Green Tea", @"Thai Shrimp Cake", @"Angry Birds Cake", @"Ham and Cheese Panini", nil]; recipes = [NSArray arrayWithObjects:recipe1, recipe2, recipe3, recipe4, recipe5, recipe6, recipe7, recipe8, recipe9, recipe10, recipe11, recipe12, recipe13, recipe14, recipe15, recipe16, nil]; thumbnails = [NSArray arrayWithObjects:@"egg_benedict.jpg", @"mushroom_risotto.jpg", @"full_breakfast.jpg", @"hamburger.jpg", @"ham_and_egg_sandwich.jpg", @"creme_brelee.jpg", @"white_chocolate_donut.jpg", @"starbucks_coffee.jpg", @"vegetable_curry.jpg", @"instant_noodle_with_egg.jpg", @"noodle_with_bbq_pork.jpg", @"japanese_noodle_with_pork.jpg", @"green_tea.jpg", @"thai_shrimp_cake.jpg", @"angry_birds_cake.jpg", @"ham_and_cheese_panini.jpg", nil]; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [recipeTitle count]; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *simpleTableIdentifier = @"RecipeCell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier]; if (cell == nil) { cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier]; } cell.textLabel.text = [recipeTitle objectAtIndex:indexPath.row]; cell.imageView.image = [UIImage imageNamed:[thumbnails objectAtIndex:indexPath.row]]; return cell; } - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"showRecipeDetail"]) { NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow]; minuteMealsDetailViewController *destViewController = segue.destinationViewController; destViewController.recipe = [recipes objectAtIndex:indexPath.row]; } NSLog(@"showRecipeDetial Segue is being passed"); } - (void)viewDidUnload { [self setTableView:nil]; [super viewDidUnload]; // Release any retained subviews of the main view. } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) { return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown); } else { return YES; } } @end
// // minuteMealsDetailViewController.h // minuteMeals // // Created by KMO on 8/18/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import <UIKit/UIKit.h> #import "Recipe.h" @interface minuteMealsDetailViewController : UIViewController @property (strong, nonatomic) IBOutlet UIImageView *recipePhoto; @property (strong, nonatomic) IBOutlet UILabel *prepTimeLabel; @property (strong, nonatomic) IBOutlet UITextView *ingredientTextView; @property (nonatomic, strong) IBOutlet UILabel *recipeLabel; @property (nonatomic, strong) NSString *recipeName; @property (nonatomic, strong) Recipe *recipe; @property (strong, nonatomic) IBOutlet UITextView *instructionTextView; @end
// // minuteMealsDetailViewController.m // minuteMeals // // Created by KMO on 8/18/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import "minuteMealsViewController.h" #import "minuteMealsDetailViewController.h" #import "Recipe.h" @interface minuteMealsDetailViewController () @end @implementation minuteMealsDetailViewController @synthesize recipePhoto; @synthesize prepTimeLabel; @synthesize ingredientTextView; @synthesize recipeLabel; @synthesize recipeName; @synthesize recipe; @synthesize instructionTextView; - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; if (self) { // Custom initialization } return self; } - (void)viewDidLoad { [super viewDidLoad]; self.title = recipe.name; self.prepTimeLabel.text = recipe.prepTime; self.recipePhoto.image = [UIImage imageNamed:recipe.imageFile]; NSMutableString *ingredientText = [NSMutableString string]; for (NSString* ingredient in recipe.ingredients) { [ingredientText appendFormat:@"%@\n", ingredient]; } self.ingredientTextView.text = ingredientText; self.instructionTextView.text = recipe.instructions; recipeLabel.text = recipeName; } - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"showInstructions"]) { minuteMealsDetailViewController *destViewController = segue.destinationViewController; destViewController.instructionTextView.text = [recipe instructions]; } NSLog(@"showInstructions Seque is being passed"); } /*- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"showRecipeDetail"]) { NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow]; minuteMealsDetailViewController *destViewController = segue.destinationViewController; destViewController.recipe = [recipes objectAtIndex:indexPath.row]; } NSLog(@"showRecipeDetial Segue is being passed"); }*/ - (void)viewDidUnload { [self setRecipePhoto:nil]; [self setPrepTimeLabel:nil]; [self setIngredientTextView:nil]; [self setInstructionTextView:nil]; [super viewDidUnload]; // Release any retained subviews of the main view. } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return (interfaceOrientation == UIInterfaceOrientationPortrait); } @end
// // Recipe.h // minuteMeals // // Created by KMO on 8/19/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import <Foundation/Foundation.h> @interface Recipe : NSObject @property (nonatomic, strong) NSString *name; // name of recipe @property (nonatomic, strong) NSString *prepTime; // preparation time @property (nonatomic, strong) NSString *imageFile; // image filename of recipe @property (nonatomic, strong) NSArray *ingredients; // ingredients @property (nonatomic, strong) NSString *instructions; // instruction set @end
// // Recipe.m // minuteMeals // // Created by KMO on 8/19/12. // Copyright (c) 2012 KAM Digital. All rights reserved. // #import "Recipe.h" @implementation Recipe @synthesize name; @synthesize prepTime; @synthesize imageFile; @synthesize ingredients; @synthesize instructions; @end
尝试先设置指令为自己的属性，并在viewDidLoad中设置标签
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"showInstructions"]) { minuteMealsDetailViewController *destViewController = segue.destinationViewController; destViewController.instructionText = [recipe instructions]; } NSLog(@"showInstructions Seque is being passed"); }
其中instructionText是一个新的属性。
并在您的instructionsViewController viewDidLoad做
instructionTextView.text = self.instructionText;
编辑：
你没有看到任何东西的原因是视图没有完全加载在prepareForSegue ，所有视图的初始化应该在viewDidLoad 。 当可以安全地更改视图时调用该方法。
你现在使用相同的viewcontroller“recipeDetail”和“说明”我build议有一个单独的viewController类为您的指示。
只需将您的指令作为viewController中的一个属性传递即可。
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { if ([segue.identifier isEqualToString:@"showInstructions"]) { MinuteMealsInstructionsViewController *destViewController = segue.destinationViewController; destViewController.instructionText = [recipe instructions]; } NSLog(@"showInstructions Seque is being passed"); }
MinuteMealsInstructionsViewController是具有instructions属性的新类。
你说你想保持配方对象中包含的配方。 而这仍然是真实的，因为你只是传递对象成员的引用。 假设你改变指令string，那么它也会在你的配方对象中改变，因为string只是一个引用。
注意：您应该根据Objective-c风格指南使用大写字母开始您的类名称。
如果你真的想在同一个viewController中做，你可以简单地传递整个配方对象destViewController.recipe = recipe; 并在viewDidLoad：
- (void)viewDidLoad { [super viewDidLoad]; self.instructionTextLabel = recipe.instructions; }