# Message wall card

> Canonical HTML: https://screenrig.ai/docs/cards/message-wall/

Moderated audience messages, one featured at a time with the next ones beside it, and a QR code to post. Display only: posting and moderation happen elsewhere.

Category: Events. Tags: Social and audience, QR codes, Events and venues, News and announcements.

## Previews

![Message wall](/cards/message-wall/v1/screenshots/canvas-bloom.webp?sha=f02b55e33dbaab83d06889d4b45b3755567598361d3860fd3e29f07968bae4af)

Canvas

![Message wall](/cards/message-wall/v1/screenshots/corner-bloom.webp?sha=83b63f8e2de7b65989d237a1137e98829e49adb05c317cca951bd2d1236267ed)

Corner

![Message wall](/cards/message-wall/v1/screenshots/chip-bloom.webp?sha=cb79eb0441eb082c82e52264ebad5d4f7cd33a3cb8544fa29998c3e061d7949a)

Chip

## Views and forms

Views: canvas, corner, chip. Canvas forms: landscape, portrait, square, strip.

[Card views, themes and publishing](/docs/cards/). [Browse the gallery](/apps/#cards).

## Data and privacy

This card uses its configured properties and live card data.

## Properties

For theme, background, accent and position, see [Common properties](/docs/cards/#common-properties).

Set static properties in `params`. Bind `data` to a project card data key for live values; that document holds only dynamic properties. Without a data key, put the complete configuration in `params`. Nested rows describe the contents of their parent property.

### Static properties

| Name | Type | Default | Values and limits | Description |
| --- | --- | --- | --- | --- |
| `title` | string | `"Message wall"` | maxLength: `40` |  |
| `postLabel` | string | `"Scan to post"` | maxLength: `30` |  |

### Dynamic properties

| Name | Type | Default | Values and limits | Description |
| --- | --- | --- | --- | --- |
| `prompt` | string | `""` | maxLength: `120` | The invitation shown beside the code, for example a question for the audience. |
| `messages` | array | `[]` | minItems: `0`; maxItems: `24` | Approved messages. The featured one advances every 8 seconds on the wall clock. |
| `messages[].text` | string |  | minLength: `1`; maxLength: `200`; Required |  |
| `messages[].author` | string | `""` | maxLength: `40` |  |
| `postUrl` | string | `""` | maxLength: `300` | The page the QR code opens to post a message. Empty hides the code. |

## Canvas example

Add this item to a playlist page’s `primitives`. [Publish the playlist and assign a screen](/docs/cards/#publish-a-card-canvas).

```json
{
  "id": "message-wall",
  "primitive": "card",
  "card": "message-wall",
  "major": 1,
  "params": {
    "theme": "neomustard"
  },
  "rect": {
    "x": 0,
    "y": 0,
    "width": 1920,
    "height": 1080
  },
  "layer": 0,
  "content_fit": "fill",
  "data": "message-wall-main"
}
```

## Write live data

Create this document before showing the card, then replace it to update the screen without republishing. Use the same project as the playlist. Supply your API authorization through the environment; see [API authentication](/docs/authentication/).

```console
curl --request PUT "https://api.screenrig.ai/api/card-data/message-wall-main" \
  --header "Authorization: Bearer $SCREENRIG_TOKEN" \
  --header "ScreenRig-Project: $SCREENRIG_PROJECT" \
  --header "Content-Type: application/json" \
  --data '{"document":{"prompt":"","messages":[],"postUrl":""}}'
```