Replace device dropdowns with radio buttons

This is closer to what the designs actually want device settings to look like, and it avoids the visual glitch in which the dropdown would render underneath the slider.

src/settings/DeviceSelection.module.css

@@ -0,0 +1,18 @@
+.selection {
+  gap: 0;
+}
+
+.title {
+  color: var(--cpd-color-text-secondary);
+  margin-block-end: 0;
+}
+
+.separator {
+  margin-block: 6px var(--cpd-space-4x);
+}
+
+.options {
+  display: flex;
+  flex-direction: column;
+  gap: var(--cpd-space-4x);
+}

src/settings/DeviceSelection.tsx

@@ -0,0 +1,71 @@
+/*
+Copyright 2024 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only
+Please see LICENSE in the repository root for full details.
+*/
+
+import { ChangeEvent, FC, useCallback, useId } from "react";
+import {
+  Heading,
+  InlineField,
+  Label,
+  RadioControl,
+  Separator,
+} from "@vector-im/compound-web";
+
+import { MediaDevice } from "../livekit/MediaDevicesContext";
+import styles from "./DeviceSelection.module.css";
+
+interface Props {
+  devices: MediaDevice;
+  caption: string;
+}
+
+export const DeviceSelection: FC<Props> = ({ devices, caption }) => {
+  const groupId = useId();
+  const onChange = useCallback(
+    (e: ChangeEvent<HTMLInputElement>) => {
+      devices.select(e.target.value);
+    },
+    [devices],
+  );
+
+  if (devices.available.length == 0) return null;
+
+  return (
+    <div className={styles.selection}>
+      <Heading
+        type="body"
+        weight="semibold"
+        size="sm"
+        as="h4"
+        className={styles.title}
+      >
+        {caption}
+      </Heading>
+      <Separator className={styles.separator} />
+      <div className={styles.options}>
+        {devices.available.map(({ deviceId, label }, index) => (
+          <InlineField
+            key={deviceId}
+            name={groupId}
+            control={
+              <RadioControl
+                checked={deviceId === devices.selectedId}
+                onChange={onChange}
+                value={deviceId}
+              />
+            }
+          >
+            <Label>
+              {!!label && label.trim().length > 0
+                ? label
+                : `${caption} ${index + 1}`}
+            </Label>
+          </InlineField>
+        ))}
+      </div>
+    </div>
+  );
+};

src/settings/SettingsModal.tsx

@@ -5,10 +5,10 @@ SPDX-License-Identifier: AGPL-3.0-only
 Please see LICENSE in the repository root for full details.
 */
 
-import { ChangeEvent, FC, ReactNode, useCallback } from "react";
+import { ChangeEvent, FC, useCallback } from "react";
 import { Trans, useTranslation } from "react-i18next";
 import { MatrixClient } from "matrix-js-sdk/src/matrix";
-import { Dropdown, Separator, Text } from "@vector-im/compound-web";
+import { Root as Form, Text } from "@vector-im/compound-web";
 
 import { Modal } from "../Modal";
 import styles from "./SettingsModal.module.css";
@@ -19,7 +19,6 @@ import { ProfileSettingsTab } from "./ProfileSettingsTab";
 import { FeedbackSettingsTab } from "./FeedbackSettingsTab";
 import {
   useMediaDevices,
-  MediaDevice,
   useMediaDeviceNames,
 } from "../livekit/MediaDevicesContext";
 import { widget } from "../widget";
@@ -33,6 +32,7 @@ import {
 import { isFirefox } from "../Platform";
 import { PreferencesSettingsTab } from "./PreferencesSettingsTab";
 import { Slider } from "../Slider";
+import { DeviceSelection } from "./DeviceSelection";
 
 type SettingsTab =
   | "audio"
@@ -70,40 +70,6 @@ export const SettingsModal: FC<Props> = ({
   );
   const [duplicateTiles, setDuplicateTiles] = useSetting(duplicateTilesSetting);
 
-  // Generate a `SelectInput` with a list of devices for a given device kind.
-  const generateDeviceSelection = (
-    devices: MediaDevice,
-    caption: string,
-  ): ReactNode => {
-    if (devices.available.length == 0) return null;
-
-    const values = devices.available.map(
-      ({ deviceId, label }, index) =>
-        [
-          deviceId,
-          !!label && label.trim().length > 0
-            ? label
-            : `${caption} ${index + 1}`,
-        ] as [string, string],
-    );
-
-    return (
-      <Dropdown
-        label={caption}
-        defaultValue={
-          devices.selectedId === "" || !devices.selectedId
-            ? "default"
-            : devices.selectedId
-        }
-        onValueChange={(id): void => devices.select(id)}
-        values={values}
-        // XXX This is unused because we set a defaultValue. The component
-        // shouldn't require this prop.
-        placeholder=""
-      />
-    );
-  };
-
   const optInDescription = (
     <Text size="sm">
       <Trans i18nKey="settings.opt_in_description">
@@ -125,33 +91,45 @@ export const SettingsModal: FC<Props> = ({
     name: t("common.audio"),
     content: (
       <>
-        {generateDeviceSelection(devices.audioInput, t("common.microphone"))}
-        {!isFirefox() &&
-          generateDeviceSelection(
-            devices.audioOutput,
-            t("settings.speaker_device_selection_label"),
-          )}
-        <Separator />
-        <div className={styles.volumeSlider}>
-          <label>{t("settings.audio_tab.effect_volume_label")}</label>
-          <p>{t("settings.audio_tab.effect_volume_description")}</p>
-          <Slider
-            label={t("video_tile.volume")}
-            value={soundVolume}
-            onValueChange={setSoundVolume}
-            min={0}
-            max={1}
-            step={0.01}
+        <Form>
+          <DeviceSelection
+            devices={devices.audioInput}
+            caption={t("common.microphone")}
           />
-        </div>
+          {!isFirefox() && (
+            <DeviceSelection
+              devices={devices.audioOutput}
+              caption={t("settings.speaker_device_selection_label")}
+            />
+          )}
+          <div className={styles.volumeSlider}>
+            <label>{t("settings.audio_tab.effect_volume_label")}</label>
+            <p>{t("settings.audio_tab.effect_volume_description")}</p>
+            <Slider
+              label={t("video_tile.volume")}
+              value={soundVolume}
+              onValueChange={setSoundVolume}
+              min={0}
+              max={1}
+              step={0.01}
+            />
+          </div>
+        </Form>
       </>
     ),
   };
 
   const videoTab: Tab<SettingsTab> = {
     key: "video",
     name: t("common.video"),
-    content: generateDeviceSelection(devices.videoInput, t("common.camera")),
+    content: (
+      <Form>
+        <DeviceSelection
+          devices={devices.videoInput}
+          caption={t("common.camera")}
+        />
+      </Form>
+    ),
   };
 
   const preferencesTab: Tab<SettingsTab> = {