Add option to play beeps on volume changes.

Only applies to output devices (aka sinks) as it just triggers the standard system beep.

Author: saivert

data/com.saivert.pwvucontrol.gschema.xml.in

@@ -26,5 +26,10 @@
             <summary>Use led style peak meter</summary>
             <description></description>
         </key>
+        <key name="beep-on-volume-changes" type="b">
+            <default>false</default>
+            <summary>Play system beep on volume change</summary>
+            <description>Lets you preview the sound level even if you don't play any audio.</description>
+        </key>
 	</schema>
 </schemalist>

data/resources/ui/window.ui

@@ -317,6 +317,10 @@
         <attribute name="label" translatable="yes">_Keyboard Shortcuts</attribute>
         <attribute name="action">win.show-help-overlay</attribute>
       </item>
+      <item>
+        <attribute name="label" translatable="yes">Beep on volume changes</attribute>
+        <attribute name="action">win.beep-on-volume-changes</attribute>
+      </item>
       <item>
         <attribute name="label" translatable="yes">_About Pwvucontrol</attribute>
         <attribute name="action">app.about</attribute>

src/ui/sinkbox.rs

@@ -60,6 +60,14 @@ mod imp {
             let item = obj.node_object().expect("nodeobj");
 
             self.volumebox.set_node_object(&item);
+
+            if matches!(item.nodetype(), NodeType::Sink) {
+                self.volumebox.imp().volume_scale.connect_volume_notify(|_| {
+                    let window = PwvucontrolWindow::default();
+                    window.play_beep();
+                });
+            }
+
             self.volumebox.set_default_node_change_handler(clone!(@weak self as widget => move || {
                 widget.obj().default_node_changed();
             }));

src/ui/window.rs

@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
+use std::time::Duration;
+
 use crate::macros::*;
 use crate::{
     application::PwvucontrolApplication,
@@ -11,12 +13,15 @@ use adw::subclass::prelude::*;
 use gettextrs::gettext;
 use glib::clone;
 use gtk::{gio, prelude::*};
+use std::cell::Cell;
+use std::time;
 
 pub enum PwvucontrolWindowView {
     Connected,
     Disconnected,
 }
 mod imp {
+
     use super::*;
 
     #[derive(Debug, gtk::CompositeTemplate)]
@@ -44,6 +49,9 @@ mod imp {
         pub info_banner: TemplateChild<adw::Banner>,
 
         pub settings: gio::Settings,
+
+        pub beep_elapsed: Cell<time::Instant>,
+        pub beep_enabled: Cell<bool>,
     }
 
     impl Default for PwvucontrolWindow {
@@ -60,6 +68,8 @@ mod imp {
                 reconnectbtn: TemplateChild::default(),
                 settings: gio::Settings::new(APP_ID),
                 info_banner: TemplateChild::default(),
+                beep_elapsed: Cell::new(std::time::Instant::now()),
+                beep_enabled: Default::default(),
             }
         }
     }
@@ -179,6 +189,13 @@ mod imp {
             self.obj().add_action(&overamplification_action);
             let use_led_peakmeter_action = self.settings.create_action("use-peakmeter-led");
             self.obj().add_action(&use_led_peakmeter_action);
+            let beep_on_volume_changes_action = self.settings.create_action("beep-on-volume-changes");
+            self.obj().add_action(&beep_on_volume_changes_action);
+
+            self.settings.connect_changed(Some("beep-on-volume-changes"), clone!(@weak self as widget => move |settings, _key| {
+                widget.beep_enabled.set(settings.boolean("beep-on-volume-changes"));
+            }));
+            self.beep_enabled.set(self.settings.boolean("beep-on-volume-changes"));
 
             self.obj().load_window_state();
         }
@@ -291,6 +308,16 @@ impl PwvucontrolWindow {
         imp.info_banner.set_title(&message);
         imp.info_banner.set_revealed(manager.node_model().n_items() == 0);
     }
+
+    pub(crate) fn play_beep(&self) {
+        if !self.imp().beep_enabled.get() {
+            return;
+        }
+        if self.imp().beep_elapsed.get().elapsed() > Duration::from_secs(1) {
+            self.display().beep();
+            self.imp().beep_elapsed.set(time::Instant::now());
+        }
+    }
 }
 
 impl Default for PwvucontrolWindow {