sound: update the volume-slider after getting a valid stream
In the ubuntu 20.04, we met an issue about the output volume-slider
on the machine with the legacy HDA audio driver, the output device
is the Speaker first (analog-stereo pa sink), then we connect a hdmi
monitor, the HDMI audio is in the output combo-box, we select the
hdmi audio (hdmi-stereo pa sink) from the combo-box, the hdmi audio
becomes the active output device now, we adjust the output volume from
the volume-slider, the slider UI is changed, but the output sound
is not changed with the UI.
The root cause is when the speaker is active, the pulseaudio only
keeps the analog-stereo sink, the sink hdmi-stereo is unlinked, when
users select the hdmi audio from UI, the pulseaudio will unlink
analo-stereo sink and create hdmi-stereo sink, but before hdmi-stereo
is created, the output_device_changed_cb() is called and
gvc_mixer_control_get_stream_from_device() returns a NULL since the
hdmi-stereo sink is not created yet in the pulseaudio. Because stream
is NULL, the output_volume_slider->stream is NULL, users can't change
the output volume via the volume-slider.
To fix it, we add a output_volume_slider->stream check in the
device_update_cb(), if it is NULL, get the stream and set it to
volume-slider. In this function, the sink hdmi-stereo is created
already, so the stream is not NULL. And this change also applies to
input as well.
sound: clear the value on level_bar when stream is empty
We met an Input Device level_bar display issue on a machine which has
no internal mic. At first there is no external mic plugged, so the
Input Device list is empty and level_bar is gray color, after we plug
an external mic, the level_bar has red color ripples, then we unplug
the external mic, the Input Device list changes to empty and we
expect the level_bar changes back to gray color, but some bars are
still red color.
Here clear the self->value to 0 if the stream is empty, then the
level_bar will change back to gray color when Input/Output device
list is empty.
Ignored in Meson < 0.60.0, deprecated since 0.60.1 and fatal since 0.61.0.
panels/applications/meson.build:10:5: ERROR: Function does not take positional arguments.
panels/background/meson.build:10:5: ERROR: Function does not take positional arguments.
panels/camera/meson.build:10:5: ERROR: Function does not take positional arguments.
[...]
display-config: Do not invert order when constructing modes
Mutter sends modes in descending order of preference. By reverting
the order via `g_list_prepend`, we get unintended side effects
such as choosing the least preferred refresh rate by default (if
the selected mode is not marked as preferred).
Instead of adding complex logic in several places, make sure that
the assumption of descending preference is kept by simply not
inverting the order.
