ChannelsView.swift

import SwiftUI
import StreamChat

struct ChannelsView: View {
    @State
    var channels: [ChatChannel] = []
    @State
    var createTrigger = false
    @State
    var searchTerm = ""
    
    var body: some View {
        VStack {
            // createChannelView
            // searchView
            List(channels, id: \.self) { channel in
                NavigationLink(destination: chatView(id: channel.cid)) {
                    Text(channel.name ?? channel.cid.id)
                }
            }.onAppear(perform: loadChannels)
        }
        .navigationBarItems(trailing: 
            Button(action: { self.createTrigger = true }) { 
                Text("Create") 
            }.disabled(self.createTrigger || !self.searchTerm.isEmpty)
        )
        .navigationBarTitle("Channels")
    }
    
    func chatView(id: ChannelId) -> ChatView {
        return ChatView(
            channel: ChatClient.shared.channelController(
                for: id
            ).observableObject
        )
    }
    
    func loadChannels() {
        let filter: Filter<ChannelListFilterScope>
        
        if searchTerm.isEmpty {
            filter = .and([.in("members", values: [ChatClient.shared.currentUserId!]),
                           .equal("type", to: "messaging")])
        } else {
            filter = .and([.equal("type", to: "messaging")])
        }
        
        let controller = ChatClient.shared.channelListController(query: .init(filter: filter))
        
        controller.synchronize { error in
            if let error = error {
                print(error)
                return
            }
            
            self.channels = controller.channels
                .filter {
                    if self.searchTerm.isEmpty {
                        return true
                    } else {
                        return $0.cid.id.contains(self.searchTerm)
                    }
                }
        }
    }
}