[FIX] point_of_sale: loading ticket screen

This fix prevent blank screen (when offline) & inifinte loop (when in 3G or other low connection) on order screen.

- **Offline Mode:** When accessing the order screen offline, now the screen loads previously fetched orders and displays a "Limited Functionality" popup.
- **Slow Connection (3G):** Infinite loop (caused by repeated call to  `await this.pos.getServerOrders()`)  is fixed by ensuring orders load only once, even on slow connections using the flag `loadingOrderState`

closes odoo/odoo#196810

Task-id: 4550978
Signed-off-by: Adrien Guilliams (adgu) <adgu@odoo.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/addons/point_of_sale/static/src/app/screens/ticket_screen/ticket_screen.js b/addons/point_of_sale/static/src/app/screens/ticket_screen/ticket_screen.js
index 2e60145422f..1c4bba5060a 100644
--- a/addons/point_of_sale/static/src/app/screens/ticket_screen/ticket_screen.js
+++ b/addons/point_of_sale/static/src/app/screens/ticket_screen/ticket_screen.js
@@ -24,6 +24,7 @@ import { PosOrderLineRefund } from "@point_of_sale/app/models/pos_order_line_ref
 import { fuzzyLookup } from "@web/core/utils/search";
 import { parseUTCString } from "@point_of_sale/utils";
 import { useTrackedAsync } from "@point_of_sale/app/utils/hooks";
+import { ConnectionLostError } from "@web/core/network/rpc";
 
 const NBR_BY_PAGE = 30;
 
@@ -77,10 +78,16 @@ export class TicketScreen extends Component {
 
         onMounted(this.onMounted);
         onWillStart(async () => {
-            if (this.pos._shouldLoadOrders()) {
+            if (this.pos._shouldLoadOrders() && !this.pos.loadingOrderState) {
                 try {
                     this.pos.setLoadingOrderState(true);
                     await this.pos.getServerOrders();
+                } catch (error) {
+                    if (error instanceof ConnectionLostError) {
+                        Promise.reject(error);
+                        return error;
+                    }
+                    throw error;
                 } finally {
                     this.pos.setLoadingOrderState(false);
                 }