Fixes Issue #1140

[redpandatronicsuk]

Fixes #1140
Based on a solution found at: https://stackoverflow.com/questions/56460362/how-to-force-wkwebview-to-ignore-hardware-silent-switch-on-ios
I changed the code found in the linked source from Swift to Objective-C, as required by this project. WARNING: I haven't used Swift before and very limited experience with Objective-C.

• For me this seems to work, but it is not the cleanest solution in my opinion.
• It might also be possible to play generated sound (i.e. using oscillator) instead of hardcoding the silent base64 mp3 data.
• Maybe ignoring silence switch should only be done if a parameter is supplied

Summary

Ignores the silence switch when playing audio from a WebView. Closes issue #1140

Test Plan

1. Initialise a react-native project, add react-native-webview as dependency.
2. In App.js add

<WebView injectedJavaScript={`try{var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
  var oscillator = audioCtx.createOscillator();
  oscillator.type = 'sine';
  oscillator.frequency.setValueAtTime(420, audioCtx.currentTime);
  oscillator.start();
  var oscillator_volume = audioCtx.createGain();
  oscillator_volume.gain.linearRampToValueAtTime(1, 0);
  oscillator.connect(oscillator_volume);
  oscillator_volume.connect(audioCtx.destination);
  }catch(e){}
  true;`} />

3. Launch the App
4. Toggle the silent switch on the device or simulator
5. Notice that when using this PR the silence switch is ignored, i.e. the sound from the oscillator (or any other webaudio) will be audible even when the silent switch is set to on (silence) position
6. (optional) Do the same 5 steps, but using the code from the master branch instead and notice that when setting the silence switch to on all webaudio will be muted

What's required for testing (prerequisites)?

What are the steps to reproduce (after prerequisites)?

Compatibility

OS	Implemented
iOS	✅
Android	NA

Checklist

• I have tested this on a device and a simulator

I haven't added anything to README.md, because it is just a bugfix.

I haven't added the change to CHANGELOG.md, but suppose a line could be added warning users of the new default behaviour, i.e. silence switch is ignored.

[safaiyeh]

Thanks for the PR @redpandatronicsuk Can you add an example to the example app, so it is easier to test & future testing of the feature?

[redpandatronicsuk]

@safaiyeh I added the parameter you requested and added documentation for it.

Video, I think, still behaves differently.

Another problem I noticed is that the silence switch is initially ignored, i.e. when you first open the app with the silent switch on, the sound plays. Then you have to toggle it on and off again for it to mute the sound. That was the previous behaviour too but probably needs fixing too. What do you think?

[redpandatronicsuk]

@safaiyeh I made a demo that better explains what I am describing above here: https://github.com/redpandatronicsuk/react-native-webview-hardware-silence-switch-demo-

It shows the inconsistencies with the hardware silence switch using web audio and video. Besides the bug that the hardware switch is initially ignored, I think the behaviour of audio is correct now. For consistency, I think video should behave the same. Just to be clear, this PR hasn't changed video behaviour in any way, the demo just showcases the inconsistencies.

[redpandatronicsuk]

Not sure what has changed here. I have however made the change you have requested, i.e. the parameter to make the new behaviour optional. See the commits below.

[redpandatronicsuk]

@safaiyeh I can see the status is still as changes requested, but I already made the changes and committed them. How can I change the status back to Review required?

[safaiyeh]

hi @redpandatronicsuk thanks for making the changes! I'll check this out soon.

[redpandatronicsuk]

Thanks @safaiyeh, I'll wait for you to review the changes, just wasn't sure if I submitted them correctly as I can still see the Changes requested message even after making the changes.

[safaiyeh]

One last piece of feedback @redpandatronicsuk, also we should update Guide.md with some more information about this,

[redpandatronicsuk]

@safaiyeh thanks for your feedback. I've made your requested changes. Please feel free to edit the text I added to Guide.md. Maybe we should add a section Inconsistencies to Guide.md that highlights inconsistencies across platforms, etc. and put it under that section?

[react-native-community-bot]

🎉 This PR is included in version 9.2.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[enahum]

After upgrading to 9.2.0 Xcode is complaining that _ignoreSilentHardwareSwitch is not defined

[redpandatronicsuk]

Just added the changes to RNCWebView.h, must have forgotten to include that in the commit.

[redpandatronicsuk]

The change is here: https://github.com/redpandatronicsuk/react-native-webview/blob/0eac0c2d80d0aab18b1c9a14e43c9c6593e0aa72/ios/RNCWebView.h#L62
How can I include this in this PR now?

[enahum]

so I guess a new PR is incoming to fix it and bump the version number

[safaiyeh]

Yup, submit a new PR @redpandatronicsuk :)

[safaiyeh]

Thanks for the instant feedback @enahum

[redpandatronicsuk]

I've made a new PR here now: #1319 @safaiyeh can you please double check this includes all the changed files now

[fungilation]

Can't build with upgrade to RN-webview 9.2. Previously fine at 9.1.4. My app's build Xcode errors: