[iOS] AirPlay 與雙螢幕支援

AirPlay 與雙螢幕⽀支援Johnny Sung

2013.10.17 @ CocoaHeads Taipei

Friday, October 18, 13



Apple TV• Lightning Digital AV Adapter• Lightning to VGA Adapter• Apple 30-pin Digital AV Adapter• Apple 30-pin to VGA Adapter



- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

self.viewController = [[ViewController alloc] initWithNibName:@"ViewController" bundle:nil];

self.window.rootViewController = self.viewController;

[self.window makeKeyAndVisible];

return YES;

}

這是我們常常在AppDelegate看到的句⼦子


剛剛在didFinishLaunchingWithOptions做了...

• ⽤用UIScreen的⼤大⼩小，來建⽴立 UIWindow

• 宣告⼀一個ViewController

• 指定rootViewController

• 讓此Window提到最前，並且可被看⾒見


UIScreen

UIWindow

UIViewController


螢幕數量變動的時機

⼿手機螢幕

⼿手機螢幕

第⼆二螢幕

第⼆二螢幕

didFinishLaunchingWithOptions

UIScreenDidConnectNotification

• APP執⾏行中，連接螢幕

• APP剛開啓時


我們要做的

• APP啓動時

• 檢查⺫⽬目前螢幕的數量註冊螢幕連接/斷開的notification

• 將對應的UIWindow設定好

• 收到螢幕連接的notification時

• 建⽴立對應的UIWindow並且設定


NSArray* screens = [UIScreen screens];for (UIScreen *screen in screens){ if (screen == [UIScreen mainScreen]) { self.window = [[UIWindow alloc] initWithFrame:[screen bounds]]; [self.window setScreen:screen]; ViewControllerA* vcA=[ViewControllerA alloc] initWithNibName:@"xibA" bundle:nil]; self.window.rootViewController = vcA; [self.window makeKeyAndVisible]; } else { self.window2 = [[UIWindow alloc] initWithFrame:[screen bounds]]; [self.window2 setScreen:screen]; ViewControllerB* vcB=[ViewControllerB alloc] initWithNibName:@"xibB" bundle:nil]; self.window2.rootViewController = vcB; self.window2.hidden=NO; }}

根據UIScreen設定對應的UIWindow


註冊螢幕連接/斷開的notification (1/2)

在 application:didFinishLaunchingWithOptions: 裡

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(screenDidConnect:) name:UIScreenDidConnectNotification object:nil]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(screenDidDisconnect:) name:UIScreenDidDisconnectNotification object:nil];APP關閉時，記得解除註冊

在 applicationWillTerminate: 裡

[[NSNotificationCenter defaultCenter] removeObserver:self name:UIScreenDidConnectNotification object:nil]; [[NSNotificationCenter defaultCenter] removeObserver:self name:UIScreenDidDisconnectNotification object:nil];


註冊螢幕連接/斷開的notification (2/2)

- (void) screenDidConnect:(NSNotification *) notification{ UIScreen* screen = [notification object]; // 建⽴立UIWindow ...

}


使⽤用雙螢幕之後

• 偵測第⼆二螢幕的解析度，並調整UI樣式

• 第⼆二螢幕的控制與溝通


取得ViewController⺫⽬目前的解析度

在 viewDidLoad 裡

CGRect screenRect = [[[[self view] window] screen] bounds];CGFloat screenWidth = screenRect.size.width;CGFloat screenHeight = screenRect.size.height;NSLog(@"Screen: %.0f x %.0f", screenWidth, screenHeight);


Example:

https://github.com/j796160836/AirplayDemoTest

Ref.

• AirplayDemo

https://github.com/quellish/AirplayDemo

• ExternalDisplay

https://developer.apple.com/library/ios/samplecode/ExternalDisplay/Introduction/Intro.html











Reference

• Using Windows to Present Content on Multiple Displayshttps://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/WindowAndScreenGuide/Introduction/Introduction.html

• Understanding Windows and Screenshttps://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/WindowAndScreenGuide/WindowScreenRolesinApp/WindowScreenRolesinApp.html

• Presenting Content on an External Displayhttps://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/WindowAndScreenGuide/UsingExternalDisplay/UsingExternalDisplay.html#//apple_ref/doc/uid/TP40012555-CH3-SW1

• UIScreen Class Referencehttps://developer.apple.com/library/ios/documentation/uikit/reference/UIScreen_Class/Reference/UIScreen.html

• UIWindow Class Referencehttps://developer.apple.com/library/ios/documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html


https://developer.apple.com/library/ios/documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html




























Q & A


螢幕鏡射與否？

• 啓動雙螢幕（與⼿手機螢幕獨⽴立）[self.window2 setScreen:screen];

self.window2.hidden=NO;

• 使⽤用鏡射（與⼿手機螢幕相同）[self.window2 setScreen:nil];

self.window2.hidden=YES;


將self.viewController = [[ViewController alloc] initWithNibName:@"ViewController" bundle:nil];

換成UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle: nil];

self.viewController = [mainStoryboard instantiateViewControllerWithIdentifier:@"ViewController"];

使⽤用 StoryBoard ?


腦筋急轉彎

試問

• [UIScreen mainScreen].bounds

• [UIApplcation sharedApplication].keyWindow.bounds

的差異？

http://stackoverflow.com/questions/17465547/uiscreen-mainscreen-bounds-vs-uiapplcation-sharedapplication-keywindow-bound




Technology

[iOS] AirPlay 與雙螢幕支援