Hook Setup

example/App.tsx

@@ -1,21 +1,20 @@
 import { NavigationContainer } from '@react-navigation/native'
-import React from 'react'
 import { Button, Platform } from 'react-native'
 import { QueryClient, QueryClientProvider } from 'react-query'
+import { XmtpProvider } from 'xmtp-react-native-sdk'
 
 import ConversationCreateScreen from './src/ConversationCreateScreen'
 import ConversationScreen from './src/ConversationScreen'
 import HomeScreen from './src/HomeScreen'
 import LaunchScreen from './src/LaunchScreen'
 import { Navigator } from './src/Navigation'
 import TestScreen from './src/TestScreen'
-import { XmtpContextProvider } from './src/XmtpContext'
 
 const queryClient = new QueryClient()
 export default function App() {
   return (
     <QueryClientProvider client={queryClient}>
-      <XmtpContextProvider>
+      <XmtpProvider>
         <NavigationContainer>
           <Navigator.Navigator>
             <Navigator.Screen
@@ -71,7 +70,7 @@ export default function App() {
             />
           </Navigator.Navigator>
         </NavigationContainer>
-      </XmtpContextProvider>
+      </XmtpProvider>
     </QueryClientProvider>
   )
 }

example/src/ConversationCreateScreen.tsx

@@ -1,9 +1,9 @@
 import { NativeStackScreenProps } from '@react-navigation/native-stack'
 import React, { useState } from 'react'
 import { Button, ScrollView, Text, TextInput } from 'react-native'
+import { useXmtp } from 'xmtp-react-native-sdk'
 
 import { NavigationParamList } from './Navigation'
-import { useXmtp } from './XmtpContext'
 
 export default function ConversationCreateScreen({
   route,

example/src/ConversationScreen.tsx

@@ -8,7 +8,7 @@ import * as ImagePicker from 'expo-image-picker'
 import type { ImagePickerAsset } from 'expo-image-picker'
 import { PermissionStatus } from 'expo-modules-core'
 import moment from 'moment'
-import React, { useRef, useState } from 'react'
+import React, { useCallback, useMemo, useRef, useState } from 'react'
 import {
   Button,
   FlatList,
@@ -30,11 +30,10 @@ import {
   DecodedMessage,
   StaticAttachmentContent,
   ReplyContent,
-  Client,
+  useClient,
 } from 'xmtp-react-native-sdk'
 
 import { NavigationParamList } from './Navigation'
-import { useXmtp } from './XmtpContext'
 import {
   useConversation,
   useMessage,
@@ -57,7 +56,7 @@ export default function ConversationScreen({
 }: NativeStackScreenProps<NavigationParamList, 'conversation'>) {
   const { topic } = route.params
   const messageListRef = useRef<FlatList>(null)
-  let {
+  const {
     data: messages,
     refetch: refreshMessages,
     isFetching,
@@ -74,10 +73,15 @@ export default function ConversationScreen({
     fileUri: attachment?.image?.uri || attachment?.file?.uri,
     mimeType: attachment?.file?.mimeType,
   })
-  messages = (messages || []).filter(
-    (message) => !hiddenMessageTypes.includes(message.contentTypeId)
+
+  const filteredMessages = useMemo(
+    () =>
+      (messages ?? [])?.filter(
+        (message) => !hiddenMessageTypes.includes(message.contentTypeId)
+      ),
+    [messages]
   )
-  // console.log("messages", JSON.stringify(messages, null, 2));
+
   const sendMessage = async (content: any) => {
     setSending(true)
     console.log('Sending message', content)
@@ -102,16 +106,22 @@ export default function ConversationScreen({
   const sendRemoteAttachmentMessage = () =>
     sendMessage({ remoteAttachment }).then(() => setAttachment(null))
   const sendTextMessage = () => sendMessage({ text }).then(() => setText(''))
-  const scrollToMessageId = (messageId: string) => {
-    const index = (messages || []).findIndex((m) => m.id === messageId)
-    if (index === -1) {
-      return
-    }
-    return messageListRef.current?.scrollToIndex({
-      index,
-      animated: true,
-    })
-  }
+  const scrollToMessageId = useCallback(
+    (messageId: string) => {
+      const index = (filteredMessages || []).findIndex(
+        (m) => m.id === messageId
+      )
+      if (index === -1) {
+        return
+      }
+      return messageListRef.current?.scrollToIndex({
+        index,
+        animated: true,
+      })
+    },
+    [filteredMessages]
+  )
+
   return (
     <SafeAreaView style={{ flex: 1 }}>
       <KeyboardAvoidingView
@@ -142,7 +152,7 @@ export default function ConversationScreen({
             contentContainerStyle={{ paddingBottom: 100 }}
             refreshing={isFetching || isRefetching}
             onRefresh={refreshMessages}
-            data={messages}
+            data={filteredMessages}
             inverted
             keyboardDismissMode="none"
             keyExtractor={(message) => message.id}
@@ -154,9 +164,9 @@ export default function ConversationScreen({
                 onReply={() => setReplyingTo(message.id)}
                 onMessageReferencePress={scrollToMessageId}
                 showSender={
-                  index === (messages || []).length - 1 ||
-                  (index + 1 < (messages || []).length &&
-                    messages![index + 1].senderAddress !==
+                  index === (filteredMessages || []).length - 1 ||
+                  (index + 1 < (filteredMessages || []).length &&
+                    filteredMessages![index + 1].senderAddress !==
                       message.senderAddress)
                 }
               />
@@ -1046,7 +1056,7 @@ function MessageContents({
   contentTypeId: string
   content: any
 }) {
-  const { client }: { client: Client<any> } = useXmtp()
+  const { client } = useClient()
 
   if (contentTypeId === 'xmtp.org/text:1.0') {
     const text: string = content
@@ -1080,8 +1090,8 @@ function MessageContents({
   if (contentTypeId === 'xmtp.org/reply:1.0') {
     const replyContent: ReplyContent = content
     const replyContentType = replyContent.contentType
-    const codec = client.codecRegistry[replyContentType]
-    const actualReplyContent = codec.decode(replyContent.content)
+    const codec = client?.codecRegistry[replyContentType]
+    const actualReplyContent = codec?.decode(replyContent.content)
 
     return (
       <View>

example/src/HomeScreen.tsx

@@ -9,9 +9,8 @@ import {
   Text,
   View,
 } from 'react-native'
-import { Conversation, Client } from 'xmtp-react-native-sdk'
+import { Conversation, Client, useXmtp } from 'xmtp-react-native-sdk'
 
-import { useXmtp } from './XmtpContext'
 import { useConversationList, useMessages } from './hooks'
 
 /// Show the user's list of conversations.

example/src/LaunchScreen.tsx

@@ -1,10 +1,10 @@
 import { NativeStackScreenProps } from '@react-navigation/native-stack'
-import React from 'react'
+import React, { useCallback } from 'react'
 import { Button, ScrollView, StyleSheet, Text, View } from 'react-native'
 import * as XMTP from 'xmtp-react-native-sdk'
+import { useXmtp } from 'xmtp-react-native-sdk'
 
 import { NavigationParamList } from './Navigation'
-import { useXmtp } from './XmtpContext'
 import { useSavedKeys } from './hooks'
 
 const appVersion = 'XMTP_RN_EX/0.0.1'
@@ -22,24 +22,26 @@ export default function LaunchScreen({
 }: NativeStackScreenProps<NavigationParamList, 'launch'>) {
   const { setClient } = useXmtp()
   const savedKeys = useSavedKeys()
-  const configureWallet = (
-    label: string,
-    configuring: Promise<XMTP.Client>
-  ) => {
-    console.log('Connecting XMTP client', label)
-    configuring
-      .then(async (client) => {
-        console.log('Connected XMTP client', label, {
-          address: client.address,
+  const configureWallet = useCallback(
+    (label: string, configuring: Promise<XMTP.Client>) => {
+      console.log('Connecting XMTP client', label)
+      configuring
+        .then(async (client) => {
+          console.log('Connected XMTP client', label, {
+            address: client.address,
+          })
+          setClient(client)
+          navigation.navigate('home')
+          // Save the configured client keys for use in later sessions.
+          const keyBundle = await client.exportKeyBundle()
+          await savedKeys.save(keyBundle)
         })
-        setClient(client)
-        navigation.navigate('home')
-        // Save the configured client keys for use in later sessions.
-        const keyBundle = await client.exportKeyBundle()
-        await savedKeys.save(keyBundle)
-      })
-      .catch((err) => console.log('Unable to connect XMTP client', label, err))
-  }
+        .catch((err) =>
+          console.log('Unable to connect XMTP client', label, err)
+        )
+    },
+    []
+  )
   return (
     <ScrollView>
       <Text

example/src/hooks.tsx

@@ -7,9 +7,9 @@ import {
   EncryptedLocalAttachment,
   ReactionContent,
   RemoteAttachmentContent,
+  useXmtp,
 } from 'xmtp-react-native-sdk'
 
-import { useXmtp } from './XmtpContext'
 import { downloadFile, uploadFile } from './storage'
 
 /**

src/context/XmtpContext.tsx

@@ -0,0 +1,36 @@
+import * as React from 'react'
+
+import { Client } from '../lib/Client'
+
+export interface XmtpContextValue {
+  /**
+   * The XMTP client instance
+   */
+  client: Client<any> | null
+  /**
+   * Set the XMTP client instance
+   */
+  setClient: React.Dispatch<React.SetStateAction<Client<any> | null>>
+}
+
+export const XmtpContext = React.createContext<XmtpContextValue>({
+  client: null,
+  setClient: () => {},
+})
+interface Props {
+  children: React.ReactNode
+  client?: Client<any>
+}
+export const XmtpProvider: React.FC<Props> = ({
+  children,
+  client: initialClient,
+}) => {
+  const [client, setClient] = React.useState<Client<any> | null>(
+    initialClient ?? null
+  )
+  const context = React.useMemo(
+    () => ({ client, setClient }),
+    [client, setClient]
+  )
+  return <XmtpContext.Provider value={context}>{children}</XmtpContext.Provider>
+}

src/context/index.ts

@@ -0,0 +1 @@
+export * from './XmtpContext'

src/hooks/index.ts

@@ -0,0 +1,2 @@
+export * from './useXmtp'
+export * from './useClient'

src/hooks/useClient.ts

@@ -0,0 +1,80 @@
+import { Signer } from 'ethers'
+import { useCallback, useRef, useState } from 'react'
+
+import { useXmtp } from './useXmtp'
+import { Client, ClientOptions } from '../lib/Client'
+
+interface InitializeClientOptions {
+  signer: Signer
+  options?: ClientOptions
+}
+
+export const useClient = (onError?: (e: Error) => void) => {
+  const [isLoading, setIsLoading] = useState(false)
+  const [error, setError] = useState<Error | null>(null)
+  // client is initializing
+  const initializingRef = useRef(false)
+
+  const { client, setClient } = useXmtp()
+  /**
+   * Initialize an XMTP client
+   */
+  const initialize = useCallback(
+    async ({ options, signer }: InitializeClientOptions) => {
+      // only initialize a client if one doesn't already exist
+      if (!client && signer) {
+        // if the client is already initializing, don't do anything
+        if (initializingRef.current) {
+          return undefined
+        }
+
+        // flag the client as initializing
+        initializingRef.current = true
+
+        // reset error state
+        setError(null)
+        // reset loading state
+        setIsLoading(true)
+
+        let xmtpClient: Client<any>
+
+        try {
+          // create a new XMTP client with the provided keys, or a wallet
+          xmtpClient = await Client.create(signer ?? null, {
+            ...options,
+          })
+          setClient(xmtpClient)
+        } catch (e) {
+          setClient(null)
+          setError(e as Error)
+          onError?.(e as Error)
+          // re-throw error for upstream consumption
+          throw e
+        }
+
+        setIsLoading(false)
+
+        return xmtpClient
+      }
+      return client
+    },
+    [client, onError, setClient]
+  )
+
+  /**
+   * Disconnect the XMTP client
+   */
+  const disconnect = useCallback(async () => {
+    if (client) {
+      setClient(null)
+    }
+  }, [client, setClient])
+
+  return {
+    client,
+    error,
+    initialize,
+    disconnect,
+    isLoading,
+  }
+}