This is needed to re-parent the VolumeSlider window, as there is only a
single VolumeSlider, but two different VolumeButtons and their
respective NSPopover windows. So, always recreate the view on open,
which doesn't appear to have a noticeable impact on performance.
Fixes#331
Signed-off-by: Christopher Snowhill <kode54@gmail.com>
Only initialize viewController once, the first time the volume control
is opened. Re-initializing it can cause an error assigning it as first
responder to the volume slider popover view.
Signed-off-by: Christopher Snowhill <kode54@gmail.com>
Christopher Snowhill