Session drawer: DESKTOP in Steam sessions opens the desktop with Steam in it

Big Picture's own Switch to Desktop waits on SteamOS Manager and never finishes here. The
drawer's Steam row gets a DESKTOP button beside STEAM and QAM: the session ends and the desktop
starts in its place with Steam's desktop client open (the relaunch the Steam Desktop UI button
uses).

app/src/main/java/com/droiddeck/launcher/SessionActivity.kt

@@ -301,6 +301,16 @@ class SessionActivity : ComponentActivity(), SurfaceHolder.Callback {
                         onHardwareKeyboard = { drawerOpen = false; pcKeyboardOpen = !pcKeyboardOpen },
                         onSteamMenu = if (SessionState.mode == SessionService.MODE_STEAM) ({ sendSteamGuide() }) else null,
                         onQam = if (SessionState.mode == SessionService.MODE_STEAM) ({ triggerSteamQam() }) else null,
+                        // The desktop with Steam's desktop client in it, in this session's place: the
+                        // session ends with status 0 and onSessionEnded starts the relaunch (Stop's
+                        // finish() would skip it).
+                        onSwitchToDesktop = if (SessionState.mode == SessionService.MODE_STEAM) ({
+                            drawerOpen = false
+                            SessionState.relaunch = Intent(this@SessionActivity, SessionActivity::class.java)
+                                .putExtra(SessionService.EXTRA_MODE, SessionService.MODE_DESKTOP)
+                                .putExtra(SessionService.EXTRA_STEAM_UI, "desktop")
+                            SessionService.stop(this@SessionActivity)
+                        }) else null,
                         backActionsInverted = backActionsInverted,
                         onBackActionsInverted = { inverted ->
                             SessionPrefs.setBackActionsInverted(this@SessionActivity, inverted)

app/src/main/java/com/droiddeck/launcher/ui/SessionOverlay.kt

@@ -213,6 +213,8 @@ class DrawerActions(
     val onHardwareKeyboard: () -> Unit,
     val onSteamMenu: (() -> Unit)?,
     val onQam: (() -> Unit)?,
+    /** Steam sessions: end Big Picture and open the desktop with Steam's desktop client in it. */
+    val onSwitchToDesktop: (() -> Unit)? = null,
     val onOsc: (String) -> Unit,
     val onSuspendPolicy: (String) -> Unit,
     val onBackActionsInverted: (Boolean) -> Unit,
@@ -346,6 +348,26 @@ fun SessionDrawer(open: Boolean, page: Int, controllerActive: Boolean, onPageCha
                         ) {
                             Text("QAM", fontSize = 13.sp, fontWeight = FontWeight.SemiBold, letterSpacing = 0.5.sp)
                         }
+                        // Big Picture's own "Switch to Desktop" waits on SteamOS Manager for ever
+                        // here; this does the switch without the client.
+                        if (a.onSwitchToDesktop != null) {
+                            val deskSrc = remember { MutableInteractionSource() }
+                            val deskHot = deskSrc.collectIsFocusedAsState().value || deskSrc.collectIsHoveredAsState().value
+                            OutlinedButton(
+                                onClick = { host.open = null; a.onSwitchToDesktop.invoke() },
+                                interactionSource = deskSrc,
+                                modifier = Modifier.weight(1f).height(48.dp).then(focus.track(page, "desktop"))
+                                    .semantics { contentDescription = "Switch to Desktop" }.controllerConfirm {
+                                        host.open = null
+                                        a.onSwitchToDesktop.invoke()
+                                    },
+                                shape = RoundedCornerShape(12.dp),
+                                border = BorderStroke(if (deskHot) 2.dp else 1.dp, if (deskHot) pal.signal else colors.outline),
+                                colors = ButtonDefaults.outlinedButtonColors(containerColor = if (deskHot) pal.signal.copy(alpha = 0.16f) else Color.Transparent),
+                            ) {
+                                Text("DESKTOP", fontSize = 13.sp, fontWeight = FontWeight.SemiBold, letterSpacing = 0.5.sp)
+                            }
+                        }
                     }
                 }