Warn to save content

Signed-off-by: Mark Tolmacs <mark@lazycat.hu>

excalidraw-app/App.tsx

@@ -126,6 +126,8 @@ import DebugCanvas, {
   loadSavedDebugState,
 } from "./components/DebugCanvas";
 import { AIComponents } from "./components/AI";
+import type { SaveWarningRef } from "./components/SaveWarning";
+import { SaveWarning } from "./components/SaveWarning";
 
 polyfill();
 
@@ -331,6 +333,8 @@ const ExcalidrawWrapper = () => {
 
   const [langCode, setLangCode] = useAppLangCode();
 
+  const activityRef = useRef<SaveWarningRef | null>(null);
+
   // initial state
   // ---------------------------------------------------------------------------
 
@@ -615,6 +619,8 @@ const ExcalidrawWrapper = () => {
       collabAPI.syncElements(elements);
     }
 
+    activityRef.current?.activity();
+
     // this check is redundant, but since this is a hot path, it's best
     // not to evaludate the nested expression every time
     if (!LocalData.isSavePaused()) {
@@ -856,6 +862,7 @@ const ExcalidrawWrapper = () => {
           setTheme={(theme) => setAppTheme(theme)}
           refresh={() => forceRefresh((prev) => !prev)}
         />
+        <SaveWarning ref={activityRef} />
         <AppWelcomeScreen
           onCollabDialogOpen={onCollabDialogOpen}
           isCollabEnabled={!isCollabDisabled}

excalidraw-app/components/SaveWarning.tsx

@@ -0,0 +1,40 @@
+import { forwardRef, useImperativeHandle, useRef } from "react";
+import { t } from "../../packages/excalidraw/i18n";
+import { getShortcutKey } from "../../packages/excalidraw/utils";
+
+export type SaveWarningRef = {
+  activity: () => Promise<void>;
+};
+
+export const SaveWarning = forwardRef<SaveWarningRef, {}>((props, ref) => {
+  const dialogRef = useRef<HTMLDivElement | null>(null);
+  const timerRef = useRef<NodeJS.Timeout | null>(null);
+
+  useImperativeHandle(ref, () => ({
+    /**
+     * Call this API method via the ref to hide warning message
+     * and start an idle timer again.
+     */
+    activity: async () => {
+      if (timerRef.current != null) {
+        clearTimeout(timerRef.current);
+        dialogRef.current?.classList.remove("animate");
+      }
+
+      timerRef.current = setTimeout(() => {
+        timerRef.current = null;
+        dialogRef.current?.classList.add("animate");
+      }, 5000);
+    },
+  }));
+
+  return (
+    <div ref={dialogRef} className="alert-save">
+      <div className="dialog">
+        {t("alerts.saveYourContent", {
+          shortcut: getShortcutKey("CtrlOrCmd + S"),
+        })}
+      </div>
+    </div>
+  );
+});

excalidraw-app/index.scss

@@ -1,3 +1,13 @@
+@mixin animate($animation,$duration,$method,$times){
+  animation: $animation $duration $method $times;
+}
+
+@mixin keyframes($name){
+  @keyframes #{$name}{
+      @content;
+  }
+}
+
 .excalidraw {
   --color-primary-contrast-offset: #625ee0; // to offset Chubb illusion
 
@@ -18,6 +28,43 @@
     margin-inline-start: auto;
   }
 
+  .alert-save {
+    position: absolute;
+    z-index: 10;
+    left: 0;
+    right: 0;
+    bottom: 10vh;
+    margin-inline: auto;
+    width: fit-content;
+
+    opacity: 0;
+    transition: all 0s;
+
+    &.animate {
+      opacity: 1;
+      transition: all 0.2s ease-in;
+    }
+
+    .dialog {
+      margin-inline: 10px;
+      padding: 1rem;
+      padding-inline: 1.25rem;
+
+      resize: none;
+      white-space: pre-wrap;
+      box-sizing: border-box;
+
+      background-color: var(--color-warning);
+      border-radius: var(--border-radius-md);
+      border: 1px solid var(--dialog-border-color);
+
+      font-size: 0.875rem;
+      text-align: center;
+      line-height: 1.5;
+      color: var(--color-text-warning);
+    }
+  }
+
   .encrypted-icon {
     border-radius: var(--space-factor);
     color: var(--color-primary);

packages/excalidraw/locales/en.json

@@ -230,7 +230,8 @@
     "resetLibrary": "This will clear your library. Are you sure?",
     "removeItemsFromsLibrary": "Delete {{count}} item(s) from library?",
     "invalidEncryptionKey": "Encryption key must be of 22 characters. Live collaboration is disabled.",
-    "collabOfflineWarning": "No internet connection available.\nYour changes will not be saved!"
+    "collabOfflineWarning": "No internet connection available.\nYour changes will not be saved!",
+    "saveYourContent": "Don't forget to save your content ({{shortcut}})!"
   },
   "errors": {
     "unsupportedFileType": "Unsupported file type.",