[FL-3383, FL-3413] Archive and file browser fixes (#2862)

* File browser: flickering and reload fixes
* The same for archive browser

applications/main/archive/helpers/archive_browser.c

@@ -64,8 +64,20 @@ static void
     if(!is_last) {
         archive_add_file_item(browser, is_folder, furi_string_get_cstr(item_path));
     } else {
+        bool load_again = false;
         with_view_model(
-            browser->view, ArchiveBrowserViewModel * model, { model->list_loading = false; }, true);
+            browser->view,
+            ArchiveBrowserViewModel * model,
+            {
+                model->list_loading = false;
+                if(archive_is_file_list_load_required(model)) {
+                    load_again = true;
+                }
+            },
+            true);
+        if(load_again) {
+            archive_file_array_load(browser, 0);
+        }
     }
 }
 
@@ -111,6 +123,26 @@ bool archive_is_item_in_array(ArchiveBrowserViewModel* model, uint32_t idx) {
     return true;
 }
 
+bool archive_is_file_list_load_required(ArchiveBrowserViewModel* model) {
+    size_t array_size = files_array_size(model->files);
+
+    if((model->list_loading) || (array_size >= model->item_cnt)) {
+        return false;
+    }
+
+    if((model->array_offset > 0) &&
+       (model->item_idx < (model->array_offset + FILE_LIST_BUF_LEN / 4))) {
+        return true;
+    }
+
+    if(((model->array_offset + array_size) < model->item_cnt) &&
+       (model->item_idx > (int32_t)(model->array_offset + array_size - FILE_LIST_BUF_LEN / 4))) {
+        return true;
+    }
+
+    return false;
+}
+
 void archive_update_offset(ArchiveBrowserView* browser) {
     furi_assert(browser);
 

applications/main/archive/helpers/archive_browser.h

@@ -64,6 +64,7 @@ inline bool archive_is_known_app(ArchiveFileTypeEnum type) {
 }
 
 bool archive_is_item_in_array(ArchiveBrowserViewModel* model, uint32_t idx);
+bool archive_is_file_list_load_required(ArchiveBrowserViewModel* model);
 void archive_update_offset(ArchiveBrowserView* browser);
 void archive_update_focus(ArchiveBrowserView* browser, const char* target);