Networking Images Media

const res = await fetch(`${API}/items`, {
  headers: { Authorization: `Bearer ${token}` },
});
if (!res.ok) throw new Error(`HTTP ${res.status}`);
const data: Item[] = await res.json();

await fetch(`${API}/items`, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    Authorization: `Bearer ${token}`,
  },
  body: JSON.stringify({ title }),
});

const ac = new AbortController();
const t = setTimeout(() => ac.abort(), 12_000);
try {
  const res = await fetch(url, { signal: ac.signal });
  return await res.json();
} finally {
  clearTimeout(t);
}

import { Image } from "expo-image";
 
<Image
  source={{ uri }}
  style={{ width: 120, height: 120 }}
  contentFit="cover"
  transition={200}
/>

<Image source={{ uri }} style={styles.hero} contentFit="contain" />

import { Image } from "expo-image";
 
await Image.prefetch(uri);

import * as ImagePicker from "expo-image-picker";
 
const result = await ImagePicker.launchImageLibraryAsync({
  mediaTypes: ["images"],
  quality: 0.8,
});
if (!result.canceled) setUri(result.assets[0].uri);

const cam = await ImagePicker.requestCameraPermissionsAsync();
if (!cam.granted) {
  // show rationale / open settings
  return;
}
await ImagePicker.launchCameraAsync({ quality: 0.8 });

import * as DocumentPicker from "expo-document-picker";
 
const res = await DocumentPicker.getDocumentAsync({ type: "application/pdf" });
if (!res.canceled) setFile(res.assets[0]);

import * as MediaLibrary from "expo-media-library";
 
const { status } = await MediaLibrary.requestPermissionsAsync();
if (status === "granted") await MediaLibrary.saveToLibraryAsync(localUri);

// Conceptual controlled player:
// <VideoView player={player} style={{ width: "100%", height: 220 }} />

import NetInfo from "@react-native-community/netinfo";
 
const state = await NetInfo.fetch();
if (!state.isConnected) setOffline(true);

const form = new FormData();
form.append("file", {
  uri: localUri,
  name: "photo.jpg",
  type: "image/jpeg",
} as unknown as Blob);
await fetch(`${API}/upload`, { method: "POST", body: form, headers: { Authorization: `Bearer ${token}` } });

async function getWithRetry(url: string, attempts = 3) {
  let last: unknown;
  for (let i = 0; i < attempts; i++) {
    try {
      const res = await fetch(url);
      if (res.ok) return res.json();
      last = res.status;
    } catch (e) {
      last = e;
    }
    await new Promise((r) => setTimeout(r, 300 * 2 ** i));
  }
  throw last;
}

const source = uri.startsWith("http") ? { uri } : { uri: localFileUri };