How should we control sound on/off in sonified sims?

[jbphet]

Sonification enabled/disabled is going to be a global setting. How should the user control it?

[jbphet]

This was discussed in the 6/14/2018 design meeting, and we decided to add a smallish control to the right side of the nav bar.

[jbphet]

@samreid suggested looking at KeyboardHelpButton button as an example of how to add this.

[jbphet]

@pixelzoom pointed out that there is a flag named accessible that is supported in the package.json files for each sim that is used to control whether the KeyboardHelpButton is enabled, so I should look at how that is used and follow a similar pattern for how a sim decides whether to display and hook up the volume on/off button.

[jbphet]

During the design meeting mentioned above, we decided that I'd prototype this and present it to the group rather than having anyone create mockups first.

[pixelzoom]

Re #11 (comment)...

Since the sound button applies to both "basic" and "enhanced" (sonification) sound, I think the appearance of the button in the navigation bar more likely depends on whether a Sound manager has been instantiated. The controls for selecting between "basic" and "enhanced" in the PhET menu may require option(s), to indicate whether the sim supports "basic" and/or "enhanced" sounds.

[jbphet]

The sound on/off button has been added to the nav bar (see the issue referenced above for the commits). I think it's okay to close this issue.