Audio and video calling overview

The OpenIM HarmonyOS SDK provides call signaling APIs to initiate, accept, reject, cancel, and hang up calls, as well as query active group rooms, refresh room credentials, and restore unhandled incoming invitations.

The SDK manages signaling channels and room session metadata; it does not handle camera capture, microphone input, remote media rendering, or calling UI components. Pass the provided roomID, token, and liveURL to your selected WebRTC or third-party real-time media engine, and manage hardware permissions, media tracks, quality monitoring, and UI presentation in application code.

Lifecycle workflow

1. The caller constructs a complete SignalingInvitationInfo payload and initiates an invitation via Start single call or Start group call.
2. The invitee listens for incoming calls in Handle call events, or retrieves pending invitations during application cold starts via Restore pending call invitation.
3. The callee calls Accept call to obtain room credentials and join the media engine session, or dismisses the call UI via Reject call.
4. During an active call, synchronize room status using the unique roomID, and track individual participant presence using each participant's userID.
5. The caller can cancel an unanswered call using Cancel call, while connected participants end active sessions using Hang up call.

The SignalingParticipantMetaData object contains the participant's IMUser profile, while OfflinePushInfo defines push notification payloads delivered when invitees are offline. Room tokens are time-sensitive; always use the token returned by the active invitation or re-fetch valid tokens before joining media channels.

Resolving a signaling Promise, receiving signaling events, and executing room status queries represent three separate stages. Resolving a signaling API call does not imply that remote RTC channels are connected or that remote peers have rendered updated UI views.