add js memory tutorial (#2421)

docs/tutorial/node/src/main_tiles_from_js.js

@@ -0,0 +1,23 @@
+// Copyright © SixtyFPS GmbH <info@slint-ui.com>
+// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-commercial
+
+// ANCHOR: main
+// main.js
+let slint = require("slint-ui");
+let ui = require("./memory.slint");
+let mainWindow = new ui.MainWindow();
+
+let initial_tiles = mainWindow.memory_tiles;
+let tiles = initial_tiles.concat(initial_tiles.map((tile) => Object.assign({}, tile)));
+
+for (let i = tiles.length - 1; i > 0; i--) {
+    const j = Math.floor(Math.random() * i);
+    [tiles[i], tiles[j]] = [tiles[j], tiles[i]];
+}
+
+let model = new slint.ArrayModel(tiles);
+mainWindow.memory_tiles = model;
+
+mainWindow.run();
+
+// ANCHOR_END: main