I currently have background music that starts up when the app opens and runs an infinite loop until the user goes into the settings and turns the music off using this
-(IBAction)stopMusicButton{
[(AppDelegate*)[UIApplication sharedApplication].delegate stopMusic];
}
They can also resume the music in the settings page. What I'm a confused about is how to stop the other sounds in my app from playing if the user doesn't want the noise. For example, when the user navigates the menu of my app there are various sounds that play when certain things are pressed. How can I allow the user to be able to toggle these sounds on and off? There are also a few different views with their respective .h/.m files, all of which play sounds. If you could point me in the right direction I'd really appreciate it! Thanks in advance!
I use a singleton class to store settings information - you could probably use your app delegate as well. All you need is a boolean property called isSoundMuted or something like that. Set that whenever the sound is muted or unmuted, then check the variable's value before playing any sounds in an if block.
if (MySingletonClass.isSoundMuted == NO)
{
[self playSound]
}
Related
Is there a quick and easy way to have the app go back to the same screen after I put it in background mode?
I know there are frameworks just for this stuff, but has anyone done it without much sweat?
Thanks
In your app delegate, add a line to the applicationDidenterBackground: method that stores the current page via NSUserDefaults.
Then in the applicationWillEnterForeground: method, load up that saved value and restore the page.
Multitasking should enable this, while a device has enough memory to keep your app open. Otherwise how about using NSUserDefaults to store a string reference to your view?
As of iOS 5.1, there is no quick and easy way.
Here is some background information, otherwise skip ahead to the question in bold. I am building an app and I would like it to have access to the remote control/lock screen events. The tricky part is that this app does not play audio itself, it controls the audio of another device nearby. The communication between devices is not a problem when the app is in the foreground. As I just found out, an app does not assume control of the remote controls until it has played audio with a playback audio session, and was the last do so. This presents a problem because like I said, the app controls ANOTHER device's audio and has no need to play its own.
My first inclination is to have the app play a silent clip every time it is opened in order to assume control of the remote controls. The fact that I have to do this makes me wonder if I am even going to be allowed to do it by Apple or if there is another way to achieve this without fooling the system with fake audio clips.
QUESTION(S): Will Apple approve an app that plays a silent audio clip in order to assume control of the remote/lock screen controls for the purpose of controlling another device's audio? Is there any way of assuming control of the remote controls without an audio session?
P.S. I would prefer to have this functionality on iOS 4.0 and up.
P.P.S I have seen this similar question and it has gotten me brainstorming but the answer provided is not specific to what I need to know.
NOTE: As of iOS 7.1, you should be using MPRemoteCommandCenter instead of the answer below.
You create various system-provided subclasses of MPRemoteCommand and assign them to properties of the [MPRemoteCommandCenter sharedCommandCenter].
I'm keeping the rest of this around for historical reference, but the following is not guaranteed to work on recent iOS versions. In fact, it just might not.
You definitely do need an audio player but not necessarily an explicit session to take control of the remote control events. (AVAudioSession is implicit to any app that plays audio.) I spent a decent amount of time playing with this to confirm this.
I've seen a lot of confusion on the internet about where to set up the removeControlEventRecievedWithEvent: method and various approaches to the responder chain. I know this method works on iOS 6 and iOS 7. Other methods have not. Don't waste your time handling remote control events in the app delegate (where they used to work) or in a view controller which may go away during the lifecycle of your app.
I made a demo project to show how to do this.
Here's a quick rundown of what has to happen:
You need to create a subclass of UIApplication. When the documentation says UIResponder, it means UIApplication, since your application class is a subclass of UIResponder. In this subclass, you're going to implement the remoteControlReceivedWithEvent: and canBecomeFirstResponder methods. You want to return YES from canBecomeFirstResponder. In the remote control method, you'll probably want to notify your audio player that something's changed.
You need to tell iOS to use your custom class to run the app, instead of the default UIApplication. To do so, open main.m and change this:
return UIApplicationMain(argc, argv, nil, NSStringFromClass([RCAppDel`egate class]));
to look like this:
return UIApplicationMain(argc, argv, NSStringFromClass([RCApplication class]), NSStringFromClass([RCAppDelegate class]));
In my case RCApplication is the name of my custom class. Use the name of your subclass instead. Don't forget to #import the appropriate header.
OPTIONAL: You should configure an audio session. It's not required, but if you don't, audio won't play if the phone is muted. I do this in the demo app's delegate, but do so where appropriate.
Play something. Until you do, the remote controls will ignore your app. I just took an AVPlayer and gave it the URL of a streaming site that I expect to be up. If you find that it fails, put your own URL in there and play with it to your heart's content.
This example has a little bit more code in there to log out remote events, but it's not all that complicated. I just define and pass around some string constants.
I bet that a silent looping MP3 file would help work towards your goal.
Moshe's solution worked great for me! However one issue I noticed is when you paused the audio, the media controls would go away and you won't be able to play it again without going back into the app. If you set the Media Info on the lock screen when you play the audio then this won't happen:
NSDictionary *mediaInfo = #{MPMediaItemPropertyTitle: #"My Title",
MPMediaItemPropertyAlbumTitle: #"My Album Name",
MPMediaItemPropertyPlaybackDuration: [NSNumber numberWithFloat:0.30f]};
[[MPNowPlayingInfoCenter defaultCenter] setNowPlayingInfo:mediaInfo];
I am using the iPad settings app to change some button sounds and a background image. It all works well and the settings are maintained from one app launch to another in the simulator. Now I have implemented a toggle switch to either set sets of sounds off or on. When the app launches, whatever state the switch is in, it works; e.g. if the "Alert Sounds" switch is OFF the alert sounds are silent and if I change it to ON the sounds will start working. However, if I turn the switch back OFF the sounds still keep working. However, if the state is ON when the app launches, the sounds work, but will not be silenced when the switch is set to OFF.
Note that this is different than the settings not taking effect until a second round of settings. That was a previous problem I solved (thanks to stack overflow) by using:
- (void)applicationDidBecomeActive:(UIApplication *)application
{
[[NSUserDefaults standardUserDefaults] synchronize];
}
I have methods named:
- (void)defaultsChanged:(NSNotification *)NSUserDefaultsDidChangeNotification
(which is called when the notification is sent)
and
-(void)setValuesFromPreferences
(which is called in ViewDidLoad)
The logic looks like this in both:
// Set alert sounds from preferences
NSString *alertSoundPreference = [userDefaults stringForKey:kAlertSound];
BOOL alertSoundEnabled = [userDefaults boolForKey:kAlertSoundEnabled];
if (alertSoundEnabled)
{
// Create the URLs for the alert audio files
// Store the alert sound URLs as a CFURLRef instances
// Create system sound objects representing the alert sound files
}
I do not have an else, because I assume that no sound resources will be specified if alertSoundEnabled is NO.
I have searched for explanations and tutorials that mention this problem but have not found any yet, so I'm asking here. Thanks for any suggestions.
viewDidLoad is not necessarily called when the app becomes active again (nor does viewWill/DidAppear, IIRC), as the whole point of iOS 4+ multitasking is to prevent such loading/unloading and recreation of objects on app-switching.
If I had to guess, the sounds are already allocated when the user had the switch ON at original launch/viewDidLoad; however, if your code does nothing to explicitly disassociate them when it loads back up, they would continue playing, as they are all already set up.
As such, I'd try adding an else clause that (upon alertSoundEnabled == NO) destroys your system sound objects.
My App is a view-based application. At the beginning I show my logo and after a delay of a few seconds it changes into another view. from then on the user can switch to a lot of different views.
Sooooo.. My Problem: The thing is, when I restart my App. [..well closing and reopen by touching the icon..] the app itself doesnt restart in the sence of jumping to the very first view. to the contrary: at restart the user just returns to the last view that was open.
So I dont know why this is.
Is it normal to somehow manually tell the app to return to the very first view after restart? And if so, how do I have to do that?
PS.
I have so no idea what to do.. Maybe my problem has to do with the timer i used in the first view to change after a delay of time?
Please, is there anyone, who can help me?
Your problem is that, as of iPhone 4, returning to the home screen does not terminate your app. It's just made inactive, so opening it again reactivates it. In most cases, this is a good thing. If it doesn't work for your app, you can add the UIApplicationExitsOnSuspend key to your Info.plist with a value of YES.
(As I said, you should only do this if it really helps usability. If it's just about getting your splash screen shown again, most users and possibly Apple will frown upon it.)
iOS 4.0 and greater have a fast-start thing that allows apps to restart back from where they were upon restarting. There are several ways to deal with this:
1.) your App Delegate receives info about being but into the background and resumed. - (void)applicationDidBecomeActive:(UIApplication *)application and - (void)applicationDidEnterBackground:(UIApplication *)application are the relevant functions here. Check the docs.
2.) You can also disable the background, inactive state completely by including UIApplicationExitsOnSuspend in you Info.plist as Chuck already pointed out.
Overall, you should check the application state docs on Apple's Side.
How would I play songs or make a splash screen for my cocoa app? I know it's a simple question but I am a complete noob when it comes to cocoa.
You want to create an application delegate class and implement the -applicationWillFinishLaunching and -applicationDidFinishLaunching methods to display/hide your splash screen or start/stop your audio. You can connect an instance of this class as the application's delegate in Interface Builder in the project's MainMenu.xib.
Keep in mind that it's generally considered bad form to have to display a splash/load screen in Mac apps. If your app can start instantly and lazily load resources or load them in a background thread, it provides a much nicer experience for your users.
Barry is right, you have to get rid of this idea to use splash screens.. it's mainly a M$ Windows concept and it is kind of frustrating for the user to wait for the app to load itself, and I bet you won't load a thing and you just want to show a splash screen so you can feel important, but I'm telling you: apps with "marketing-only" splash screens are trash right from the beginning, because the user waits for absolutely nothing to load, and he/she will immediatelly get sick of seeing it every single time the app starts..
Now, about the songs.. I'll help you on this one, but I'm telling you again: it's useless, can't see the usefullness in having a sound play on every startup... so putting sound and a splash screen to your app startup will scare most users away, and your app won't made it!
So, to load a song you use the NSSound class like this:
NSSound *s = [[NSSound alloc] initWithContentsOfFile:songPath byReference:YES];
and then you can control it with the following methods:
[s play]
[s pause]
[s resume]
[s stop]