AVAudioSession setCategory Swift 4.2 iOS 12 - Play Sound on Silent

问题

To play sound even on Silent mode I use to use below method. But how it's not working.

// Works on Swift 3  
do {
    try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
} catch {
    print(error)
}

How to get it work in 4.2 / iOS 12?

In newer version we need to set mode and options.

try AVAudioSession.sharedInstance().setCategory(
    <#T##category:AVAudioSession.Category##AVAudioSession.Category#>,
    mode: <#T##AVAudioSession.Mode#>, 
    options: <#T##AVAudioSession.CategoryOptions#>)`

回答1:

Her der Töne's comment shows you the new syntax, but you also need to activate the audio session after setCategory:

do {
    try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default)
    try AVAudioSession.sharedInstance().setActive(true)
} catch {
    print(error)
}

回答2:

As a workaround, you can call the Objective-C AVAudioSession.setCategory: method with the NSObject.performSelector::

if #available(iOS 10.0, *) {
    try! AVAudioSession.sharedInstance().setCategory(.playback, mode: .moviePlayback)
}
else {
    // Workaround until https://forums.swift.org/t/using-methods-marked-unavailable-in-swift-4-2/14949 isn't fixed
    AVAudioSession.sharedInstance().perform(NSSelectorFromString("setCategory:error:"), with: AVAudioSession.Category.playback)
}

If you want to set the category and options for iOS 9 and earlier then use:

AVAudioSession.sharedInstance().perform(NSSelectorFromString("setCategory:withOptions:error:"), with: AVAudioSession.Category.playback, with:  [AVAudioSession.CategoryOptions.duckOthers])

UPDATE:

Issue is fixed in Xcode 10.2.

回答3:

For Swift 4.2 in iOS 12, it is simply:

try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .default, options: [])

回答4:

Update for Xcode 10.2:

Apple finally fix this issue in Xcode 10.2. 
So no need to add these workaround code anymore if you use Xcode 10.2 or newer version.

But you also could refer this code for any problem like this.

You can use an objective-c category to help to fix this issue.

Create a AVAudioSession+Swift.h:

@import AVFoundation;

NS_ASSUME_NONNULL_BEGIN

@interface AVAudioSession (Swift)

- (BOOL)swift_setCategory:(AVAudioSessionCategory)category error:(NSError **)outError NS_SWIFT_NAME(setCategory(_:));
- (BOOL)swift_setCategory:(AVAudioSessionCategory)category withOptions:(AVAudioSessionCategoryOptions)options error:(NSError **)outError NS_SWIFT_NAME(setCategory(_:options:));

@end

NS_ASSUME_NONNULL_END

With a AVAudioSession+Swift.m:

#import "AVAudioSession+Swift.h"

@implementation AVAudioSession (Swift)

- (BOOL)swift_setCategory:(AVAudioSessionCategory)category error:(NSError **)outError {
    return [self setCategory:category error:outError];
}
- (BOOL)swift_setCategory:(AVAudioSessionCategory)category withOptions:(AVAudioSessionCategoryOptions)options error:(NSError **)outError {
    return [self setCategory:category withOptions:options error:outError];
}

@end

Then import the "AVAudioSession+Swift.h" in your <#target_name#>-Bridging-Header.h

#import "AVAudioSession+Swift.h"

Result is you can call the method in swift like before.

do {
    try AVAudioSession.sharedInstance().setCategory(.playback)
    try AVAudioSession.sharedInstance().setCategory(.playback, options: [.mixWithOthers])
    try AVAudioSession.sharedInstance().setActive(true)
} catch {
    print(error)
}

回答5:

The above answer (by Rhythmic Fistman) is correct if your app is not compatible with iOS 9 or below.

If your app is compatible with iOS 9 you will see the next error:

'setCategory' is unavailable in Swift

In that case there is a bug with Swift 4.2, this is an issue with AVFoundation in Xcode 10's SDKs, you can work around it by writing an Objective-C function that calls through to the old API, since they're still available in Objective-C.

In the next link you can read more details:

https://forums.swift.org/t/using-methods-marked-unavailable-in-swift-4-2/14949

回答6:

Paste this into your viewDidLoad()

do {
    try AVAudioSession.sharedInstance().setCategory(AVAudioSession.Category.playback, mode: AVAudioSession.Mode.default, options: [])
    try AVAudioSession.sharedInstance().setActive(true)
}
catch {
    print(error)
}

回答7:

//Swift 4.2
if #available(iOS 10.0, *) {
    try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, 
    mode: AVAudioSessionModeDefault)
} else {
 //Fallback on earlier versions
}

回答8:

Code for swift 4 :

do {
        try AKSettings.setSession(category: .playback, with: [])
        try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, mode: AVAudioSessionModeDefault, options: [])
        try AVAudioSession.sharedInstance().setActive(true)


    } catch {
        print(error)
    }

Hope that helps

回答9:

Swift 5

let audioSession = AVAudioSession.sharedInstance()
_ = try? audioSession.setCategory(.playback, options: .defaultToSpeaker)
_ = try? audioSession.setActive(true)

来源：https://stackoverflow.com/questions/51010390/avaudiosession-setcategory-swift-4-2-ios-12-play-sound-on-silent

标签

ios

swift

avfoundation

avaudiosession