We started seeing a weird issue these days. The adaptive card is not visible in Preview mode in Channel but in chat its visible. I tested a lowest Adaptive card with just one text, and I see the same behavior.
In Chats
In Channel:
Its blank completely. But when you click on Send, the card is posted perfect in Chat.
This is the code:
import { Attachment, CardFactory } from "botbuilder";
export class CustomerResultCard {
public static getCard(type: string): Attachment {
const card = CardFactory.adaptiveCard(
{
"type": "AdaptiveCard",
"body": [
{
"type": "ColumnSet",
"columns": [
{
"type": "Column",
"width": "stretch",
"items": [
{
"type": "ColumnSet",
"columns": [
{
"type": "Column",
"items": [
{
"type": "TextBlock",
"size": "Large",
"weight": "Bolder",
"text": "Entity Type:" +type+ " not supported",
"height": "stretch"
}
],
"height": "stretch",
"style": "default",
"width": 65
}
],
"height": "stretch"
}
],
"style": "default"
}
]
}
],
"$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
"version": "1.3"
}
);
return card;
}
}
The bug is resolved and we can see adaptive card in Channel preview