how to display a file using react-native - ios

Question

So, I have those "cards" to which are attached files.
I want to be able to display the content of these files (when possible; I do not expect to show binary files obviously, but text, pdf, images,...) to the user.
Upon a longPress on an attachment, the openAttachment() function is be called. That function downloads the file from the server if necessary and then (tries to) open it:
// Opens an attachment
const openAttachment = async (attachment) => {
try {
// Download file if not already done
const fileInfo = await FileSystem.getInfoAsync(FileSystem.cacheDirectory + attachment.name)
let uri
if (!fileInfo.exists) {
console.log('Downloading attachment')
resp = await FileSystem.downloadAsync(
server.value + `/index.php/apps/deck/api/v1.0/boards/${route.params.boardId}/stacks/${route.params.stackId}/cards/${route.params.cardId}/attachments/${attachment.id}`,
FileSystem.cacheDirectory + attachment.name,
{
headers: {
'Authorization': token.value
},
},
)
console.log(resp)
uri = await FileSystem.getContentUriAsync(resp.uri)
} else {
console.log('File already in cache')
uri = await FileSystem.getContentUriAsync(fileInfo.uri)
}
console.log('Opening file ' + uri)
Sharing.shareAsync(uri);
} catch {
Toast.show({
type: 'error',
text1: i18n.t('error'),
text2: error.message,
})
console.log(error)
}
}
The issue always arrise at the Sharing.shareAsync(uri); line: Whatever I put there, it fails:
Sharing.shareAsync(uri) does not seem to be supported on my platform: https://docs.expo.dev/versions/latest/sdk/sharing/
Linking.openURL(uri) does not support the file:// scheme (the uri is in the form file:///var/mobile/Containers/Data/Application/5C1CB402-5ED1-4E17-B907-46111AE3FB7C/Library/Caches/test.pdf)
await WebBrowser.openBrowserAsync(uri) (from expo-web-browser) does not seem to be able to open local files
How am I supposed to do to display those files? Anyone has an idea?
Cyrille

Answer 1

I found a solution using react-native-file-viewer
// Opens an attachment
const openAttachment = async (attachment) => {
try {
// Download file if not already done
const fileInfo = await FileSystem.getInfoAsync(FileSystem.cacheDirectory + "attachment.name")
let uri
if (!fileInfo.exists) {
console.log('Downloading attachment')
const resp = await FileSystem.downloadAsync(
server.value + `/index.php/apps/deck/api/v1.0/boards/${route.params.boardId}/stacks/${route.params.stackId}/cards/${route.params.cardId}/attachments/${attachment.id}`,
FileSystem.cacheDirectory + attachment.name,
{
headers: {
'Authorization': token.value
},
},
)
console.log(resp)
uri = await FileSystem.getContentUriAsync(resp.uri)
} else {
console.log('File already in cache')
uri = await FileSystem.getContentUriAsync(fileInfo.uri)
}
console.log('opening file', uri)
FileViewer.open(uri)
} catch(error) {
Toast.show({
type: 'error',
text1: i18n.t('error'),
text2: error.message,
})
console.log(error)
}
}