屏幕共享

// 应用内采集：只有本 App 的画面，切到其它 App 后对端看到的画面会停住
let track = srtc.createLocalScreenTrack(preset: .h1080p)

// 全屏采集：整个系统屏幕，切到任何 App 都继续共享
let track = srtc.createLocalScreenTrack(
    preset: .h720p,
    mode: .broadcast(appGroup: "group.your.app.group")
)

let screenTrack = srtc.createLocalScreenTrack(preset: .h1080p)
try await screenTrack.startCapture()
try await channel.publishLocalTrack(screenTrack)

import SRTC

@available(macOS 12.3, *)
func startScreenShare(srtc: SRTCEngine, channel: Channel) async throws {
    let displays = try await ScreenCaptureSources.availableDisplays()
    let windows = try await ScreenCaptureSources.availableWindows()

    // 业务层自行展示选择 UI，这里以第一块显示器为例
    let selectedSource = displays.first

    let screenTrack = srtc.createLocalScreenTrack(
        source: selectedSource,
        preset: .h1080p
    )
    try await screenTrack.startCapture()
    try await channel.publishLocalTrack(screenTrack)
}

let screenTrack = srtc.createLocalScreenTrack(
    source: selectedSource,
    preset: .h1080p,
    audioPreset: .default
)

try await screenTrack.startCapture()
try await channel.publishLocalTrack(screenTrack)

let screenTrack = srtc.createLocalScreenTrack(preset: .h1080p)
try await screenTrack.startCapture()
try await channel.publishLocalTrack(screenTrack)

import SRTCBroadcastKit

class SampleHandler: SRTCBroadcastSampleHandler {}

<key>SRTCAppGroupIdentifier</key>
<string>group.your.app.group</string>

let screenTrack = srtc.createLocalScreenTrack(
    preset: .h720p,
    mode: .broadcast(appGroup: "group.your.app.group")
)
screenTrack.delegates.add(delegate: self)

try await screenTrack.startCapture()               // 只是开始监听，此时还没有画面
try await channel.publishLocalTrack(screenTrack)

import SRTC
import SwiftUI

struct ShareButton: View {
    var body: some View {
        SRTCBroadcastPicker(
            preferredExtension: "com.your.app.broadcast",   // 扩展的 Bundle ID
            title: "开始共享"
        )
        .frame(width: 64, height: 32)
    }
}

extension MyState: TrackDelegate {
    func screenBroadcastDidStart(_ track: Track) {
        // 扩展已连上，画面开始传输 —— 这才是"共享中"
    }

    func screenBroadcastDidFinish(_ track: Track, reason: String) {
        // 用户点了系统胶囊、或广播被系统中断。监听仍然保留，用户可以再次发起
    }
}

try await channel.unpublishLocalTrack(screenTrack)
try await screenTrack.stopCapture()