squeek school 4

Разработка приложений для iOSзанятие #4

squeek school

суббота, 30 апреля 2011 г.

View Controller

• Управляет содержимым экрана

• Наследуй от UIViewController, чтобы определить свою логику

• Несколько ViewController-ов могут совмещаться

“Your” and “Our” View Controllers• Create your own UIViewController subclass for each screenful• Plug them together using existing composite view controllers

View Controller

View Controller

View Controller

NavigationController

25Friday, January 22, 2010

“Your” and “Our” View Controllers• Create your own UIViewController subclass for each screenful• Plug them together using existing composite view controllers

View Controller

View Controller

View Controller

Tab BarController



свой ViewController

#import <UIKit/UIKit.h>@interface MyViewController : UIViewController {NSMutableArray *myData; UILabel *myLabel;}

@property (readonly) NSArray *myData;- (void)doSomeAction:(id)sender;

view объявлен в UIViewController

Creating Your View in Code• Override -loadView

■ Never call this directly

• Create your views• Set the view property• Create view controller with -init

// Subclass of UIViewController- (void)loadView{

}

MyView *myView = [[MyView alloc] initWithFrame:frame];

[myView release];self.view = myView; // The view controller now owns the view




- (void)loadView {MyView *myView = [[MyView alloc] initWithFrame:frame];self.view = myView; [myView release];}



• File - New File - View Controller

• автоматическое создание nib-файла

• создание нового объекта viewController при помощи -initWithNibName:bundle:

Creating Your View with Interface Builder• Lay out a view in Interface Builder• File’s owner is view controller class• Hook up view outlet• Create view controller

with -initWithNibName:bundle:



Навигация• UINavigationController

• UITabBarController

• UIScrollView


UINavigationControllerUINavigationController

• Stack of view controllers• Navigation bar

View Controller

View Controller

View Controller


5Thursday, January 28, 2010

UINavigationController• Stack of view controllers• Navigation bar

View Controller

View Controller

View Controller




управление набором ViewController

- (void)pushViewController:(UIViewController *)viewControlleranimated:(BOOL)animated;

!!!вызывается retain

- (UIViewController *)popViewControllerAnimated:(BOOL)animated;

pop обычно не вызывается, автоматически при нажатии ‘<-’


первый ViewController

- (void)applicationDidFinishLaunching}

navController = [[UINavigationController alloc] init];

[navController pushViewController:firstViewController animated:NO];

[window addSubview:navController.view];}


а как использовать?

- (void)someAction:(id)sender {}

UIViewController *viewController = ...; [self.navigationController pushViewController:viewControlle animated:YES];

}


посмотрим?

•New Window-Based app•Новый ViewController с кнопкой•NavigationController и FirstViewController в AppDelegate•SecondViewController•Cвойство title у ViewController


как связать все ViewController?

• Не стоит использовать глобальные переменные или AppDelagate

• Что нужно на входе следующему ViewController? (и только это!)

Best Practices for Data Flow• Figure out exactly what needs to be communicated• Define input parameters for your view controller

List Controller

Detail Controller

Data


• В обратную сторону - используя делегаты (с помощью протоколов)


бонусы к навигацииCustomizing Navigation• Buttons or custom controls• Interact with the entire screen



UINavigationTitle

• Содержится у любого ViewControllerNavigation Item Ownership

View Controller

Right Bar Button Item

Navigation Item

Left Bar Button Item

Title View

22Thursday, January 28, 2010суббота, 30 апреля 2011 г.

кнопки справа и слева

• UIBarButtonItem отображается сверху

• Отображает строку, изображение• Target + Action (как и во всех кнопках)


создание UIBarButtonItem

Text Bar Button Item

- (void)viewDidLoad{

UIBarButtonItem *fooButton = [[UIBarButtonItem alloc]initWithTitle:@"Foo”style:UIBarButtonItemStyleBorderedtarget:selfaction:@selector(foo:)];

self.navigationItem.leftBarButtonItem = fooButton;

[fooButton release];}


- (void)viewDidLoad {UIBarButtonItem *fooButton = [[UIBarButtonItem alloc] initWithTitle:@"Foo” style:UIBarButtonItemStyleBordered target:self action:@selector(foo:)];

self.navigationItem.leftBarButtonItem = fooButton; [fooButton release];

}

System Bar Button Item


UIBarButtonItem *addButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAddstyle:UIBarButtonItemStyleBorderedtarget:selfaction:@selector(add:)];

self.navigationItem.rightBarButtonItem = addButton;

[addButton release];}


- (void)viewDidLoad {UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd style:UIBarButtonItemStyleBordered target:selfaction:@selector(add:)];

self.navigationItem.rightBarButtonItem = addButton; [addButton release];}


кнопка редактирования

• реализованная практика• Very common pattern• Every view controller has one available

■ Target/action already set up

Edit/Done Button

self.navigationItem.leftBarButtonItem = self.editButtonItem;

// Called when the user toggles the edit/done button- (void)setEditing:(BOOL)editing animated:(BOOL)animated{

// Update appearance of views}


self.navigationItem.leftBarButtonItem = self.editButtonItem;

- (void)setEditing:(BOOL)editing animated:(BOOL)animated {}


вместо надписиCustom Title View• Arbitrary view in place of the title

UISegmentedControl *segmentedControl = ...self.navigationItem.titleView = segmentedControl;[segmentedControl release];



Скрыть клавиатуру

• подписаться на делегат у textField

• подписаться на событие -(BOOL)textFieldShouldReturn:(UITextField *)textField;

• [textField resignFirstResponder];


Дата в строку и обратно

• NSDateFormatter *formatter = [[NSDateFormatter alloc] init];

• [formatter setDateFormat:@”DD-MM-YYYY”];

• NSDate *date = [formatter dateFromString:string];

• NSString *string = [formatter stringFromDate:date];


UITabBarControllerUITabBarController• Array of view controllers• Tab bar

Tab BarController


UITabBarController• Array of view controllers• Tab bar

View Controller

View Controller

View Controller

Tab BarController



используем UITabBarController


// Create a tab bar controllertabBarController = [[UITabBarController alloc] init];

// Set the array of view controllerstabBarController.viewControllers = myViewControllers;

// Add the tab bar controller’s view to the window[window addSubview:tabBarController.view];









- (void)applicationDidFinishLaunching{

tabBarController = [[UITabBarController alloc] init];

NSArray *myViewControllers = [NSArray arrayWithObjects:someViewController, nil];

tabBarController.viewControllers = myViewControllers;

[window addSubview:tabBarController.view];}


добавляем картинку и надписьCreating Tab Bar Items

• Title and image


UITabBarItem *item = [[UITabBarItem alloc] initWithTitle:@“Playlists” image:[UIImage imageNamed:@“music.png”] tag:0];self.tabBarItem = item;[item release];

}


стандартный наборCreating Tab Bar Items• System item


UITabBarItem *item = [[UITabBarItem alloc] initWithTabBarSystemItem: UITabBarSystemItemBookmarks tag:0]self.tabBarItem = item;[item release];

}



а если слишком много?

More View Controllers• What happens when a tab bar controller has too many

view controllers to display at once?


More View Controllers• What happens when a tab bar controller has too many

view controllers to display at once?■ “More” tab bar item

displayed automatically■ User can navigate to

remaining view controllers


Tab Bar + Navigation ControllersMultiple parallel hierarchies


архитектураTab Bar + Navigation Controllers

Navigation Controller

View Controller

Navigation Controller

View Controller

View ControllerTab Bar Controller



squeek school 4

Education