CaptureController.md

CaptureController

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: EventTarget
Source: JSObjects/CaptureController.cs
MDN Reference: CaptureController on MDN

The CaptureController interface provides methods that can be used to further manipulate a capture session separate from its initiation via MediaDevices.getDisplayMedia(). https://developer.mozilla.org/en-US/docs/Web/API/CaptureController

Constructors

Signature	Description
CaptureController(SpawnJSObjectReference _ref)	Deserialization constructor
CaptureController()	The CaptureController constructor creates a new CaptureController object instance.

Methods

Method	Return Type	Description
SetFocusBehavior(EnumString<CaptureStartFocusBehavior> focusBehavior)	void	The CaptureController interface's setFocusBehavior() method controls whether the captured tab or window will be focused when an associated MediaDevices.getDisplayMedia() Promise fulfills, or whether the focus will remain with the tab containing the capturing app.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<CaptureController>(...) or constructor new CaptureController(...)

// Create a new CaptureController instance
const controller = new CaptureController();

// Prompt the user to share a tab, window, or screen.
const stream = await navigator.mediaDevices.getDisplayMedia({ controller });

// Query the displaySurface value of the captured video track
const [track] = stream.getVideoTracks();
const displaySurface = track.getSettings().displaySurface;

if (displaySurface === "browser") {
  // Focus the captured tab.
  controller.setFocusBehavior("focus-captured-surface");
} else if (displaySurface === "window") {
  // Do not move focus to the captured window.
  // Keep the capturing page focused.
  controller.setFocusBehavior("no-focus-change");
}

See full example on MDN