I've heard it's possible to output content from an iPad app to an external display, but the app has to be prepared for this and there are serious limitations. Any pointers?
And also, can this be done for iPhone? Is it the same?
As little indicates, you'll need to create a new UIWindow and attach it to the UIScreen for the external display. This UIWindow will host the content to be presented on the external display, so you'll need to build a distinct view hierarchy for that, separate from your main application interface. You also will need to listen for the UIScreenDidConnectNotification and UIScreenDidDisconnectNotification notifications that inform your application when the external display has been attached and removed.
I demonstrate how to do this in the video for the iPad session of my class on iTunes U, for which the course notes can be viewed here.
Matt Gemmell also did a very nice writeup on this recently, which you can read here.
The key to implementing this feature is contained in the UISCreen class:
http://developer.apple.com/iphone/library/documentation/uikit/reference/UIScreen_Class/Reference/UIScreen.html#//apple_ref/occ/clm/UIScreen/screens
Basically, your app will use UIScreen to get access to the external display screen and then set it as the screen for a new UIWindow (your app will have two UIWindows). The app can then add a ViewController to the new UIWindow that represents the second screen and off you go.
UIWindow *externalWindow.screen = [[[UIScreen screens] lastObject] retain];
[externalWindow addSubview:externalViewController.view];
It's pretty simple, but will take a little experimenting to get it working. It's a pain in the butt to debug your app on the device, since the 30-pin connector will be required to connect to the display, so cannot also be used for debugging. Perhaps there is a pass thru cable for allowing debug + external display, but I haven't had a chance to look.
Limitations:
You should be able to output video-quality bit rates, as apple has been able to achieve this with a few of their applications. That said, the external display will be limited to the screen resolution supported by the device, so things might not look crisp on your 108" LCD :-)
Platforms:
This should work on all iPads and on iPhones running 4.0+. You'll need the special cable which I believe is unique for iPhone and iPad ($30-40).
Related
I would like to create videos that needs to run on an iPad native app. The app needs to show a demonstration of a product through iPad. It needs to be interactive as well. I know we can do these in Flash, since Flash is not supported in iPad what are my options?
I appreciate any guidelines or hints. Thank you in advance
The easiest way to create interactive videos for iOS is to use Apple's HTTP Live Streaming technology. You have to create a video, embed metadata, play it using MPMoviePlayerController or AVPlayerItem, and then display clickable areas in response to metadata notifications.
Metadata should contain coordinates for the element you are tracking, eg: a dress, and a identifier for the product. You overlay this info with a clickable subview that reveals more information about the product. There are several applications of this kind in iTunes, here is one.
Once you get a working product and weeks-time of videos, the most difficult part is to perform motion tracking with the less possible human interaction. One approach is to use Adobe After Effects, another is to code your own solution based on OpenCV.
Some ideas:
You could use an MPMoviePlayerController with no controls, on loop.
Here's a solution I thought of using interactive HTML popover's over the video:
You could have a data store (say an NSDictionary), with playback times as keys.
The values could then be a custom class, which includes all the necessary data for an interactive popover on the video.
Your custom class could look something like this
#interface InteractivePopover : NSObject
{
NSString *snippetTitle;
NSString *htmlData; // could include links etc.
CGPoint popoverDisplayPoint;
// other styling attributes etc.
}
Now, when a user taps the video, it pauses it at the next 'interactive' point (by looking for the next key after the current playback time), and displays (animates on) all the popups, which you set before to show off different parts of the product.
That class might be your data store, then you create another class to handling displaying, animating, controlling, sizing (etc) these interactive popovers. It would create a UIWebView for the HTML. It would also control direction, and indication of the source point for your popover.
This is clearly very expandable because you could put images, embedded content etc into the HTML for these interactive popovers.
Anyway, that's how I would do it.
Though flash will not run on ipad you can still create apps for it with flash cs5 .
HI,
I have just submitted my first application to iTunes for approval, however, there is one thing I really want to add to it ASAP.
I would like to code into an app that it can use the TV Out functions of both the iPhone and iPad? Ideally it would work in a similar way to how keynote works i.e. you see a bit more on the iPad itself than is projected on the TV, but even just mirroring the screen would be a step in the right direction.
I have searched all over for this and all I keep getting is about downloading jailbreaks for you iPhone to mirror the screen, which doesn't really help.
Thanks in advance,
If you just want to mirror, use my TVOutManager singleton. I've put up code to do this on github: https://github.com/robterrell/TVOutManager (Hmmm... I just noticed I haven't pushed the most recent code. I'll review and push new code asap.) I wrote up some detailed info about it at http://www.touchcentric.com/blog/archives/123 if you want to know the how's and why's.
Basically, just add the files to your project, and call:
[[TVOutManager sharedInstance] startTVOut];
If you want to do more than mirroring, read the docs on UIScreen. It's fairly trivial to create a UIWindow on the external screen (steal the bits from TVOutManager if you need to) and add subviews to it. This way you could have a Keynote-like controller on the device screen, while the main display is on the external display.
http://mattgemmell.com/2010/06/01/ipad-vga-output should get you started ...
Mirroring is not possible.
But to draw on an external display, just get the UIScreen object for the external display, then set the screen property of a UIWindow to it, (making sure to set the frame correctly etc) everything in that window should be drawn on the respective display.
Relative links:
developer.apple.com/library/ios/#documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html (look at screen property)
developer.apple.com/library/ios/#documentation/uikit/reference/UIScreen_Class/Reference/UIScreen.html (look at +screens)
(I don't have any reputation => can't post clickable links)
I think, you can't do this. You can only stream videos from iPod app.
But, if you have jailbreak on your device, try this (link) or take a look at this great YouTube video (link) showing exactly what you need.
Is there any way to emulate the Videos app such that we still maintain controls on the device (iPad/iPhone), but sends the video out through the cables to the TV? I looked into screen mirroring, but it's way too slow for videos, and regardless, the UIGetScreenImage() used by screen mirroring is no longer allowed by Apple.
The Videos app seems to have exactly what I need, but I don't see anything simple to make that happen.
Update (10/15/10): So apparently movies played through UIWebView have TV-Out support, while MPMoviePlayerController movies don't.
http://rebelalfons.posterous.com/iphone-os-support-for-tv-out
However, there is a caveat: this does not work on older devices updated to the most recent iOS. That is, iPod touches, iPhone 3G & 3GS don't work, while iPhone 4 and iPads do. Hoping there's some more stuff that we can use to fill in the gaps in compability, since I know its possible. Apps like AirVideo and StreamToMe currently support this functionality.
I am not sure if there is an official way to do this. But as for your examples, AirVideo uses method Swizzling (check out: http://www.cocoadev.com/index.pl?MethodSwizzling) to override checks in Movie Player, and acting like Videos app
I guess some with some reverse engineering on SDK, you can find where the checks are made, and swizzle that method, with your custom one.
In 3.2 and later (postdating the site you link to), UIScreen has a class method, 'screens' that'll return an array of one object — the main screen — if no external display is available, or two screens — the main screen and the external screen — if a TV lead is connected. The task should be as simple as positioning the views you want to appear on the external screen within its frame and the controls you want on the device within the other.
Have you tried that?
Edited for one additional comment: also as of 3.2, it is explicitly permissible to create an MPMovieController and then grab the view from it to treat as a normal UIView rather than doing a full 'present'. So that's how you'd get a movie view that you can position as you wish.
I have an iPad app that I would like to make Universal, however this seems alarmingly difficult. I've changed things around so that I support both builds, but when building, I get lots of errors about using UIPopOvers. Here're my questions:
Why does UI_USER_INTERFACE_IDIOM() not compile or register on 3.1.3?
Can I conditionally have variables in a class definition based on UI_USER_INTERFACE_IDIOM()?
If not, should I make two different view controllers?
Thanks!
Why does UI_USER_INTERFACE_IDIOM() not
compile or register on 3.1.3?
The UI_USER_INTERFACE_IDIOM macro is only available starting with 3.2. Same restrictions for the userInterfaceIdiom property of UIDevice. This means that you can only get universal application starting with SDK 3.2.
Can I conditionally have variables in
a class definition based on
UI_USER_INTERFACE_IDIOM()?
No. The UI_USER_INTERFACE_IDIOM macro is only a runtime shortcut to get the current UI idiom of the device.
If not, should I make two different
view controllers?
If you have very different UI between the two devices, it is wiser to use two different view controllers, and to create the right one at runtime (in the application controller for example) by using the UI_USER_INTERFACE_IDIOM macro.
I had pretty good luck with just selecting the target then going to Project->Upgrade current target for iPad.
My app is pretty simple, consisting mostly of table views and webviews, but it's worth making a backup and trying...
And yes, you have to submit it as a 3.2 app that can target 3.1.*
There are also a lot of other stuff that you have to do:
Make sure that it can be viewed at any orientation (got rejected the first time for this).
Make sure that you have all the new images created. you have to have 3 or 4 icons, instead of just one like an iPhone app needed. (iPad icon, iPhone icon, small icon for spotlight, etc).
And of course iPad sized screenshots for the store.
A really nice way that I use to test if it's an iPad or iPhone is to check if the device can use a split view controller, since for the forseeable future no device with a screen as small as an iPhone will be able to use the split view controller. I just created a function to do this for me:
+(BOOL)isIpad{ return NSClassFromString(#"UISplitViewController") != nil; }
Then anywhere in my app that I want to display something different depending on device, I just do a check for it:
int width = 150;
if([NabAppDelegate isIpad]){
width = 350;
} else {
width = 150;
}
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(5,10,width,25)];
This is a lot better than checking against OS version like I've seen some suggest.
For some reason, I can't seem to locate the documentation for the above support within the foundation. I am talking about the view used by some applications to show a collection of images in a cool 3D view where you can flip through the set, much like the iPod application view of the albums.
You're looking for Cover Flow. I believe it is an unpublished API. However Open Flow is a viable replacement.
OK, found it, it's called CoverFlow - but I also note that it appears that Apple considers this a private API and thus cannot be used for apps on the App Store - can anyone confirm that it is so?