I've an app with 3 view controllers. The first one generate a 5min track and when it goes to second view it keeps on playing in setVolume:2.0 and same goes for 3rd view controller.But on third ViewCOntroller there is a UIButton that re generate the first ViewController. And when it goes back to first view controller it starts that sound again and the previous one is already playing so it's a mix.Now the sound was init on first ViewController so how can I stop it on third ViewController? It there any code that stops all the sounds playing?
You can declare the AVAudioPlayer as a global variable in your first ViewController. The effect will be that every instance of your first ViewController will be able to share the same player.
AVAudioPlayer *player;
After that you can do something like this in ViewDidLoad:
if (!player) {
AVAudioPlayer *player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
[player play];
} else if (!player.playing) {
[player play];
}
You can create a shared instance and be called from all viewController. So you can refer when to stop/play/load, etc.
#interface MainAVPlayer : AVAudioPlayer
+ (instancetype)shared;
#end
#implementation MainAVPlayer
+ (instancetype)shared {
static id _sharedInstance = nil;
static dispatch_once_t oncePredicate;
dispatch_once(&oncePredicate, ^{
_sharedInstance = [[self alloc] init];
});
return _sharedInstance;
}
#end
When accessing from other view controller call:
[[MainAVPlayer shared] initWithContentsOfURL:url error:&error];
[[MainAVPlayer shared] play];
p/s: there might be typo, writing from memory.
Related
Currently I'm working on an app that uses four protocols for communication between classes. Three are working fine, but one is still not working. I've set it up same as the others but the delegate is always losing its ID. I'm quite new to Objective-C so I can't get to the bottom of it. Here is what I did:
I have a MainViewController.h with the delegate
#property (weak, nonatomic) id <PlayerProtocol> player;
and a MainViewController.m
- (void)viewDidLoad {
[super viewDidLoad];
[[Interface sharedInstance] Init];
NSLog(#"Player ID: %#", _player);
NSLog(#"viewDidLoad: %#", self);
}
- (void)sedPlayer:(id) pointer{ //sed is no typo!
_player = pointer;
NSLog(#"sedPlayer ID: %#", _player);
NSLog(#"sedPlayer: %#", self);
}
+ (instancetype)sharedInstance {
static dispatch_once_t once;
static id sharedInstance;
dispatch_once(&once, ^{
sharedInstance = [[self alloc] init];
});
return sharedInstance;
}
In the Interface.m (NSObject)
- (void)Init {
[[MainViewController sharedInstance] sedPlayer:self];
}
And of course a protocol.h but this is not of interest as the delegate does the trouble! When I run the code I get the following output on the console:
sedPlayer ID: <Interface: 0x1700ab2e0>
sedPlayer: <MainViewController: 0x100406e30>
Player ID: (null)
viewDidLoad: <MainViewController: 0x100409550>
So it is obvious that the singleton is not working as the instance of the MainViewcontroller is different. For the singleton I'm using the dispatch_once standard method as I do with the other protocols that work fine. ARC is turned on. Does anyone has a clue what is wrong here and why the singleton is not working?
Here's how I think you ended up with two instances of the MainViewController. The first one, I assume, is created when navigating to the screen associated with MainViewController. The second one is created when you call [MainViewController sharedInstance] in Interface.m.
As the ViewController view is lazy loaded ("View controllers load their views lazily. Accessing the view property for the first time loads or creates the view controller’s views." from the Apple docs under ViewManagement), you see the viewDidLoad: <MainViewController: 0x100409550> log only once, when the first MainViewController gets navigated to and loads up the view.
Here's my suggestion:
Since you do the Interface initializing in the - (void)viewDidLoad, you might as well set self.player = [Interface sharedInstance].
The code would look something like this:
- (void)viewDidLoad {
[super viewDidLoad];
self.player = [Interface sharedInstance];
NSLog(#"Player ID: %#", _player);
NSLog(#"viewDidLoad: %#", self);
}
You should also get rid of - (void)sedPlayer:(id) pointer and + (instancetype)sharedInstance in your MainViewController. It is never a good idea to have a ViewController singleton, since you might end up messing up the navigation or having multiple states of it.
For a more in-depth article on avoiding singletons, you can check objc.io Avoiding Singleton Abuse
I'm developing a iOS app using objective-c. When the application is launched a background music is played. The background music should continue playing when the user clicks help button. Also when the user goes back to the main screen from the help screen the background music should be continuously playing.
For me a new background music is getting played along with the old background music when I navigate from help to main menu. So, I am hearing two background music now.
Could anyone help me in solving this issue?
Regards,
Bharathi.
Your problem could be solved if you retained a reference to your audio player in your UIApplicationDelegate (or some other singleton that's kept around).
//in the .h
#property (nonatomic, strong) AVAudioPlayer *player;
//in the .m
- (void) playMusic
{
if (self.player == nil) {
NSString *path = [NSString stringWithFormat:#"%#/music.mp3", [[NSBundle mainBundle] resourcePath]];
NSURL *soundUrl = [NSURL fileURLWithPath:path];
self.player = [[AVAudioPlayer alloc] initWithContentsOfURL:soundUrl error:nil];
}
if (!self.player.isPlaying) {
[self.player play];
}
}
That way you can call it wherever you need with a:
[(MyAppDelegate*)[UIApplication sharedApplication].delegate playMusic];
Though it might be to your advantage to keep around a SoundsManager class as a singleton in order to handle all the sounds that you'll need to track if you're going to need more than just this one.
I'm building an app with multiple view controllers and I have coded an audio file to play at the start up of the app. That works fine and when I click on the button to view a different screen the audio file still plays without skipping a beat just like it's supposed to but my problem arises when I click on the button to go back to the main screen. When I click to go back to the main screen the audio file plays over itself reminding me of the song Row Row Your Boat. The app is re-reading that code that tells itself to play the audio file thus playing it all over again. My problem is that I can't figure out how to make it not do that. I have coded the app to stop the audio when clicking on the start game button, which is what I want it to do but not until then. I just need help getting the app to not play the audio file over itself when going back to the main screen. The audio file is coded to play infinitely until the "start" button is clicked. If anyone can make since out of what I'm trying to say then please help me code this thing correctly. Thanks to anyone who can make it work right.
Here my code:
-(void)viewDidLoad
{
NSString *introMusic = [[NSBundle mainBundle]pathForResource:#"invadingForces" ofType:#"mp3"];
audioPlayer0 = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:introMusic] error:NULL];
audioPlayer0.delegate = self;
audioPlayer0.numberOfLoops = -1;
[audioPlayer0 play];
}
The problem is that you start a sound in a local variable when your view is loaded, start it playing on endless repeat, and then forget about it. Then you close the view controller, leaving the now-forgotten audio player playing. Next time you invoke the view controller, it's viewDidLoad method creates another audio player and starts that one playing too, and then forgets about that one. Every time you open a new copy of that view controller, you'll start yet another sound player, adding another voice to your round of "row, row, row your boat."
The naive solution is to put the code that starts the sound player in the app delegate. Set up the AVAudioPlayer as a property of you app delegate. Create a startPlaying method and a stopPlaying method. In your didFinishLaunchingWithOptions method, call startPlaying.
It's cleaner app design not to put app functionality in your app delegate, but instead create a singleton to manage sound play. (Search on "iOS singleton design pattern" to learn more.) Create an appDidLaunch method in the singleton, and call appDidLaunch from didFinishLaunchingWithOptions to start playing your sound. That way the app delegate doesn't need to have app specific logic in it, but simply calls appDidLaunch and goes on it's way.
EDIT:
If you want to call a method in the app delegate, and your app delegate is declared as:
#interface AppDelegate : UIResponder <UIApplicationDelegate>
Then you'd call it from another file like this:
First, import the app delegate's header:
#import "AppDelegate.h"
And the actual code to call your app delegate's stopPlaying method:
//Get a pointer to the application object.
UIApplication *theApp = [UIApplication sharedApplication];
//ask the application object for a pointer to the app delegate, and cast it
//to our custom "AppDelegate" class. If your app delegate uses a different
//class name, use that name here instead of "AppDelegate"
AppDelegate *theAppDelegate = (AppDelegate *)theApp.delegate;
[theAppDelegate stopPlaying];
Here's some example code to wrap an AVAudioPlayer in a singleton -
BWBackgroundMusic.h
#interface BWBackgroundMusic : NSObject
// singleton getter
+ (instancetype)sharedMusicPlayer;
/* public interface required to control the AVAudioPlayer instance is as follows -
start - plays from start - if playing stops and plays from start
stop - stops and returns play-head to start regardless of state
pause - stops and leaves play-head where it is - if already paused or stopped does nothing
continue - continues playing from where the play-head was left - if playing does nothing
replace audio track with new file - replaceBackgroundMusicWithFileOfName:
set background player to nil - destroyBackgroundMusic
NOTE:- change default track filename in .m #define */
// transport like methods
- (void)startBackgroundMusic;
- (void)stopBackgroundMusic;
- (void)pauseBackgroundMusic;
- (void)continueBackgroundMusic;
// audio source management
- (void)replaceBackgroundMusicWithFileOfName:(NSString*)audioFileName startPlaying:(BOOL)startPlaying;
- (void)destroyBackgroundMusic;
#end
BWBackgroundMusic.m
#import "BWBackgroundMusic.h"
#import <AVFoundation/AVFoundation.h> // must link to project first
#define DEFAULT_BACKGROUND_AUDIO_FILENAME #"invadingForces.mp3"
#interface BWBackgroundMusic ()
#property (strong, nonatomic) AVAudioPlayer *backgroundMusicPlayer;
#end
#implementation BWBackgroundMusic
#pragma mark Singleton getter
+ (instancetype)sharedMusicPlayer {
static BWBackgroundMusic *musicPlayer = nil;
static dispatch_once_t onceToken;
dispatch_once (&onceToken, ^{
musicPlayer = [[self alloc] init];
});
//NSLog(#"sample rate of file is %f",[musicPlayer currentSampleRate]);
return musicPlayer;
}
#pragma mark Initialiser
- (id)init {
//NSLog(#"sharedMusicPlayer from BWBackgroundMusic.h init called...");
if (self = [super init]) {
// self setup _backgroundMusicPlayer here...
// configure the audio player
NSURL *musicURL = [NSURL fileURLWithPath:[NSString stringWithFormat:#"%#/%#", [[NSBundle mainBundle] resourcePath], DEFAULT_BACKGROUND_AUDIO_FILENAME]];
NSError *error;
if (_backgroundMusicPlayer == nil) {
_backgroundMusicPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:musicURL error:&error];
}
if (_backgroundMusicPlayer == nil) {
NSLog(#"%#",[error description]);
} else {
[self makePlaybackInfinite];
[_backgroundMusicPlayer play];
}
}
return self;
}
#pragma mark Selfish methods
- (void)makePlaybackInfinite {
// access backing ivar directly because this is also called from init method
if (_backgroundMusicPlayer) {
_backgroundMusicPlayer.numberOfLoops = -1;
}
}
- (CGFloat)currentSampleRate {
NSDictionary *settingsDict = [self.backgroundMusicPlayer settings];
NSNumber *sampleRate = [settingsDict valueForKey:AVSampleRateKey];
return [sampleRate floatValue];
}
#pragma mark Transport like methods
- (void)startBackgroundMusic {
// plays from start - if playing stops and plays from start
if (self.backgroundMusicPlayer.isPlaying) {
[self.backgroundMusicPlayer stop];
self.backgroundMusicPlayer.currentTime = 0;
[self.backgroundMusicPlayer prepareToPlay];// this is not required as play calls this implicitly if not already prepared
[self.backgroundMusicPlayer play];
}
else {
self.backgroundMusicPlayer.currentTime = 0;
[self.backgroundMusicPlayer prepareToPlay];
[self.backgroundMusicPlayer play];
}
}
- (void)stopBackgroundMusic {
// stops and returns play-head to start regardless of state and prepares to play
if (self.backgroundMusicPlayer.isPlaying) {
[self.backgroundMusicPlayer stop];
self.backgroundMusicPlayer.currentTime = 0;
[self.backgroundMusicPlayer prepareToPlay];
}
else {
self.backgroundMusicPlayer.currentTime = 0;
[self.backgroundMusicPlayer prepareToPlay];
}
}
- (void)pauseBackgroundMusic {
// stops and leaves play-head where it is - if already paused or stopped does nothing
if (self.backgroundMusicPlayer.isPlaying) {
[self.backgroundMusicPlayer pause];
}
}
- (void)continueBackgroundMusic {
// continues playing from where the play-head was left - if playing does nothing
if (!self.backgroundMusicPlayer.isPlaying) {
[self.backgroundMusicPlayer play];
}
}
#pragma mark Content management
- (void)replaceBackgroundMusicWithFileOfName:(NSString*)audioFileName startPlaying:(BOOL)startPlaying {
// construct filepath
NSString *filePath = [NSString stringWithFormat:#"%#/%#", [[NSBundle mainBundle] resourcePath], audioFileName];
// make a url from the filepath
NSURL *fileUrl = [NSURL fileURLWithPath:filePath];
// construct player and prepare
NSError *error;
self.backgroundMusicPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:fileUrl error:&error];
[self.backgroundMusicPlayer prepareToPlay];
[self makePlaybackInfinite];
// if startplaying then play
if (startPlaying) {
[self.backgroundMusicPlayer play];
}
}
- (void)destroyBackgroundMusic {
// stop playing if playing
[self stopBackgroundMusic];
// destroy by setting background player to nil
self.backgroundMusicPlayer = nil;
}
#end
To use simply call [BWBackgroundMusic sharedMusicPlayer]; This will instantiate the singleton if not already instantiated, start the player automatically, and will loop infinitely by default.
Furthermore you can control it from any class that imports BWBackgroundMusic.h
For example to pause the player use
[[BWBackgroundMusic sharedMusicPlayer] pauseBackgroundMusic];
Good day.
I am developing an app to play multiple musics but I'm stuck where the music stop when I select share at the sidebar (I want the music to continue to play because user didn't pause it)
I am using api from RESideMenu and I suspect initRootController is the cause to made the music stop.
Someone suggested me to put the music at the appDelegate because the music might be deallocated when it switch view controller. However, I think that this is not a good way to do as I will later add on more musics with different image background and the architecture of the app will be very messy as I stock each music in ThemeObject and call the music in cafeViewController.
Is there a better way to do this?
This is my code >>> source.
I've check your repo and the sound seems to happen inside your ThemeObject and the only place where you create and link one of those is inside your CafeViewController. So every time the CafeViewController gets unloaded this will remove the only reference to your ThemeObject and it will be garbage collected. To check if the CafeViewController gets unloaded you could put a breakpoint inside this method:
- (void)dealloc {
// Just a line where you can put your breakpoint
}
The advice to put it inside the AppDelegate isn't completely backwards as indeed you would be better off to put it inside an object that is around all of the time. However to abuse AppDelegate as a dumping ground for all your centralised features is a bad practice. For simple apps you might be better off with a Singleton approach, where you always have one instance of an object and that object maintains itself during the existence of your application.
This is what a typical singleton looks like:
#interface ThemeManager : NSObject
#property NSArray *themes;
+ (id)sharedManager;
// Add other methods here
#end
#implementation ThemeManager
+ (id)sharedInstance {
static ThemeManager *sharedInstance = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sharedInstance = [[self alloc] init];
});
return sharedInstance;
}
- (id)init {
if (self = [super init]) {
ThemeObject *cafeTheme = [[ThemeObject alloc] initWithBackgroundImg:#"cafeBG.png" audio:#"cafeAudio"];
ThemeObject *cafeTheme1 = [[ThemeObject alloc] initWithBackgroundImg:#"cafeBG.png" audio:#"cafeAudio"];
// Create as much as you need in the same way
self.themes = #[cafeTheme, cafeTheme1]; // And add them to the array of themes
}
return self;
}
// Implement other methods
#end
So you never init directly but always ask for the shared instance by calling something like
MusicManager *manager = [MusicManager sharedInstance];
ThemeObject *firstTheme = (ThemeObject *) [manager.themes firstObject];
[firstTheme setAudioPlay];
You can start, pause, stop and change songs with this central object without worrying about the lifecycle of your ViewControllers. You also can start a song from for example CafeViewController and you can stop the song CafeViewController started from the HotelViewController when you start the Hotel song.
How do you retain a view contoller when its is popped from the stack ?
Basically i have an Mp3 Player view controller. When i'm in that view controller, i can play music. when the music is playing and i navigate to a different controller, The music stops playing, and when i navigate back to that controller, it starts another instance of it. so my guess for a fix, will probably be to retain the view controller ?
This is how i initiate my music player view controller:
NSString *songLargeArtworkURL = [self.songArtworkURL stringByReplacingOccurrencesOfString:#"large" withString:#"crop"];
MusicPlayerViewController *musicPlayer = [[MusicPlayerViewController alloc] init];
musicPlayer.songName = self.testString;
musicPlayer.songArtWork = songLargeArtworkURL;
musicPlayer.songStream = self.songStreamURL;
[self.navigationController pushViewController:musicPlayer animated:YES];
Instead of using a local variable for MusicPlayerViewController, use an instance variable. Only for the first time, allocate the musicPlayer instance. Shown below:
NSString *songLargeArtworkURL = [self.songArtworkURL stringByReplacingOccurrencesOfString:#"large" withString:#"crop"];
if(! musicPlayer) {
musicPlayer = [[MusicPlayerViewController alloc] init];
}
musicPlayer.songName = self.testString;
musicPlayer.songArtWork = songLargeArtworkURL;
musicPlayer.songStream = self.songStreamURL;
[self.navigationController pushViewController:musicPlayer animated:YES];
The above code makes sure that, only for the first time the music player is instantiated. Subsequent times, it pushes the same instance of the music player