I would like to know if it exists a way to check if device camera supports auto-focus ?
The only solution I found is to check device name in order to know if it supports auto-focus or not. But I did not like it because it did not work for future device.
Using the new AVFoundation APIs in iOS 4.0, you can check this by querying the AVCaptureDevice instance for the camera using its -isFocusModeSupported: method. The focus modes include AVCaptureFocusModeLocked, AVCaptureFocusModeAutoFocus, and AVCaptureFocusModeContinuousAutoFocus.
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Is there a way to determine whether VoiceOver is currently announcing and when it stops. I've tried UIAccessibilityVoiceOverStatusChanged but my understanding is that this is only if you switch VoiceOver on or off. Any help would be greatly appreciated. thanks.
We use otherAudioIsPlaying, the problem is some app's running in the background like some pedometer monitors etc. turn on the audio it seems and never release it so even though nothing is actually being spoken or played otherAudioIsPlaying always returns 1 until you remove the other application from the background. So now not only can you not play music but you have no idea that another application in the background will mess up this test. Apple really needs to put in an API to determine if Voice Over is currently speaking or not.
These are all the Accessibility booleans that I found in the documentation:
UIAccessibilityPostNotification
UIAccessibilityIsVoiceOverRunning
UIAccessibilityIsMonoAudioEnabled
UIAccessibilityIsClosedCaptioningEnabled
UIAccessibilityRegisterGestureConflictWithZoom
I don't think that there are any booleans to do what you are talking about.
You could use the audio session's "OtherAudioIsPlaying" property to check if another system process is using the audio hardware at the moment. It should be "true" if VoiceOver is speaking and "false" if not.
Actually this might not work properly if the user is playing music in the background. But most users running VoiceOver will usually not have any other audio enabled permanently, since it makes it harder to understand what VoiceOver is saying.
Here is an example for usage:
UInt32 otherAudioIsPlaying;
UInt32 propertySize = sizeof(otherAudioIsPlaying);
AudioSessionGetProperty(kAudioSessionProperty_OtherAudioIsPlaying,&propertySize, &otherAudioIsPlaying);
if(otherAudioIsPlaying) {
// other application is generating sound output (including VoiceOver)
// but might also be any other app (like iPod App)
}
I'm about to begin building an iPhone game that will make use of Game Center Achievements and high scores, but I'd also like to have a version that works on iPhones that don't have Game Center (i.e. iOS version < 4.1). Can I have two versions of the same app in the app store, one for game center, one for without? Or should I design the app such that if the iPhone doesn't have Game Center, it won't make use of it, and if it does, it will make use of it?
I'm going to continue researching this, just thought I'd post this question and get some feedback in the meantime. Thanks so much!
Here's the definitive response I received from one of the Apple engineers...
"We'd recommend making one version of the app which dynamically detects whether Game Center is available and uses it (or not) based on that."
Maybe create a game without it, then create the capabilities for the game center, but disable them, and only enable them if they have the right version.
I am doing the same thing. If you have GameCenter capabilities, you can use the features. If you don't, you can't.
I would not program a game without and then add it later. In my case I disable Multiplayer for non-GC users.
Also, you may want your game to work if the device has GC capabilities, but the user cannot, for whatever reason, connect to GC currently.
You can use the following function to detect if the device supports Game Center:
BOOL isGameCenterAvailable()
{
// Check for presence of GKLocalPlayer API.
Class gcClass = (NSClassFromString(#"GKLocalPlayer"));
// The device must be running running iOS 4.1 or later.
NSString *reqSysVer = #"4.1";
NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
BOOL osVersionSupported = ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending);
return (gcClass && osVersionSupported);
}
However I found that a lot of people have not updated to iOS 4.1 or are naive about Game Center. The number of users in my game is quite small even though there are so many downloads. I was actually considering moving over to Open Feint which is very much easier to implement than Game Kit and also supports older devices.
I have what i thought was a relatively simple question but i cannot find an answer to it yet. I have an iPhone app that uses GPS on one of its screens. I want to disable this screen using code when the app loads,so disable it when a iPod touch is being used. This is so it can still be useful on a iPod touch as there is a lot of functionality that a iPod touch user can use.
Thanks.
You can get there with #Aaron's answer, but that's not the way to do it. Use [CLLocationManager locationServicesEnabled]; to tell if you can determine the users's location. This is a lot more robust than making decisions based on the device model.
to get the device info..
http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIDevice_Class/Reference/UIDevice.html
NSString *deviceType = [UIDevice currentDevice].model;
I think if you are just checking for GPS then you will need to access the CLLocationManager to see if it is on or off
I'm obviously not trying to play full spectrum audio, but is there some way to customize the iPhone/iTouch system alert sounds to play a little melody on the piezo speaker? The functionality is clearly present, so I guess the question is has Apple made it available for developer use...
Thanks,
-S
There are quite a few predefined sounds you can use in the 0-2000 range. For example, the keyboard click can be called like such:
AudioServicesPlayAlertSound(1104);
There is also a way to play a custom melody on the first-generation iPod touch, but it's not pretty.
It isn't. Sorry.
Only thing you can do from an application is this (you can use any SoundID for this, really):
AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);
Discussion
Depending on the particular iPhone OS device, this function plays a short sound and may invoke vibration. Calling this function does the following on various iPhone OS devices:
iPhone—plays the specified sound and, if the user has configured the Settings application for vibration on ring, invokes vibration.
iPod touch, original—plays a short alert melody.
iPod touch, 2nd generation—plays the specified sound.
Does anyone know the recommended way to check whether the device supports specific capabilities, for example the camera. I know I can detect the device the app is on with UIDevice but I was wondering if there is a way to enumerate the device's capabilities?
I'm not sure if there is a way to enumerate all of the device's capabilities. Usually, this check is done on a capability by capability basis.
So, to use your example, if you would like to know if the device you are running on has the capability to take a picture, you would:
[UIImagePickerController isSourceTypeAvailable:
UIImagePickerControllerSourceTypeCamera];
This would return true (YES) for any iPhone, and false (NO) for any iPod Touch (at least at the time of this writing).