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CaptionSource Element

Note

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This page documents the CaptionSource element, a type used to define sources for media captions, typically within the Media element in the Adaptive Cards schema.

Important note about accessibility: In version 1.3 of the schema we introduced a label property on Inputs to improve accessibility. If the Host app you are targeting supports v1.3 you should use label instead of a TextBlock as seen in some samples below. Once most Host apps have updated to the latest version we will update the samples accordingly.

CaptionSource

Defines a source for captions.

Introduced in version 1.6

CaptionSource Properties

Property Type Required Description Version
mimeType string Yes Mime type of associated caption file (e.g. "vtt"). For rendering in JavaScript, only "vtt" is supported. For rendering in UWP, "vtt" and "srt" are supported. 1.6
url uri Yes URL to captions. 1.6
label string Yes Label of this caption to show to the user. 1.6

Properties

mimeType

Mime type of associated caption file (e.g. "vtt"). For rendering in JavaScript, only "vtt" is supported, while for rendering in UWP, "vtt" and "srt" are supported.

  • Type: string
  • Required: Yes

url

URL to captions.

  • Type: uri
  • Required: Yes

label

Label of this caption to show to the user.

  • Type: string
  • Required: Yes