I am converting Images to pdf using a npm library in react native why it is giving error of null object? - react-native

I am using react-native-image-to-pdf library to convert images to pdf in my react native app. from https://www.npmjs.com/package/react-native-image-to-pdf
var photoPath = ['https://images.pexels.com/photos/20787/pexels-photo.jpg?auto=compress&cs=tinysrgb&h=350','https://images.pexels.com/photos/20787/pexels-photo.jpg?auto=compress&cs=tinysrgb&h=350'];
const myAsyncPDFFunction = async () => {
try {
const options = {
imagePaths: photoPath,
name: 'PDFName',
};
const pdf = await RNImageToPdf.createPDFbyImages(options);
console.log(pdf.filePath);
} catch(e) {
console.log(e);
}
}
but this is giving error Error: Attempt to invoke virtual method 'int android.graphics.Bitmap.getWidth()' on a null object reference
I have also tried giving path as ['./assets/a.png', './assets/b.png']
but still getting same error

Based on the usage example, your photoPath needs to be a local file path and not a remote path.
My recommendation is to first use rn-fetch-blob to download the remote image to the device, and then pass your new local image path to react-native-image-to-pdf. Something like:
RNFetchBlob
.config({
// add this option that makes response data to be stored as a file,
// this is much more performant.
fileCache : true,
})
.fetch('GET', 'http://www.example.com/file/example.png', {
//some headers ..
})
.then(async (res) => {
// the temp file path
console.log('The file saved to ', res.path())
const options = {
imagePaths: [res.path()],
name: 'PDFName',
};
const pdf = await RNImageToPdf.createPDFbyImages(options);
})

from file path remove the text 'file://; with empty string('').
const options = {
imagePaths: [uri.replace('file://', '')],
name: 'FileName',
quality: .9, // optional compression paramter
};

replace('file://', '') it's work for me

Related

How to recieve file object from google drive in vuejs?

I want to pick files from google drive as a file object. I am working in vuejs and hence used the vue-google-picker. Google picker is actually returning URL, that I am converting to a file. My code to convert to file:
async convertToFile(docs) {
return new Promise(
resolve => {
docs.map(doc => {
if (doc.url) {
gapi.load('client', function () {
gapi.client.load('drive', 'v3', function () {
var file = gapi.client.drive.files.get({ 'fileId': doc.id, 'alt': 'media' });
console.log(file)
file.execute(function (resp) {
console.log(resp)
resolve(resp)
});
});
});
}
});
}
)
}
console.log(file) shows object like this:
While console.log(resp) shows false. If I see the network tab, then I am receiving the base64 object of the file in preview tab.
How to receive that base64 object in code? What is a method of it? I am also open to any alternative method to receive object file from google drive.
You need to await for drive.files.get method
const file = await gapi.client.drive.files.get({ 'fileId': doc.id, 'alt': 'media' });
console.log(file.body) // here will be the data

How to use moveFile react-native-fs

i need share local image on react native app, use react-native share and react-native-fs. Image is in local folder in root app named 'images'. How to share this image. Do i need copy or move image to temp and use that image for getting absolute path.
This is my code. rnfs.movefile don't work
getAssetFileAbsolutePath = async () => {
const dest =
`${RNFS.TemporaryDirectoryPath}${Math.random().toString(36)
.substring(
.7)}.png`;
const img = './images/page1.png';
try {
await RNFS.moveFile(img, dest);
console.log("dobro", dest)
} catch(err) {
console.log("greska", err)
}
}
I get error “page1.png” couldn’t be moved to “tmp” because either the former doesn’t exist, or the folder containing the latter doesn’t exist.
use rn-fetch blob with react native share
first find path of the image and convert it to base64.
then share image use react native share package
ShareFile(file) {
let imagePath = null;
RNFetchBlob.config({
fileCache: true
})
.fetch("GET", file)
// the image is now dowloaded to device's storage
.then(resp => {
// the image path you can use it directly with Image component
imagePath = resp.path();
return resp.readFile("base64");
})
.then(async base64Data => {
var base64Data = `data:image/png;base64,` + base64Data;
// here's base64 encoded image
await Share.open({ url: base64Data });
// remove the file from storage
return fs.unlink(imagePath);
});
}

React Native RNFetchBlob getting the URI of the file after download

I am developing a React Native project. What I am trying to do now is that I am downloading and saving the downloaded file to the device. I am using this package, https://www.npmjs.com/package/rn-fetch-blob for downloading the file.
This is my code
RNFetchBlob.config({
fileCache: true,
})
.fetch('GET', 'https://static.standard.co.uk/s3fs-public/thumbnails/image/2016/05/22/11/davidbeckham.jpg?w968', {
})
.then((res) => {
Alert.alert(res.path());
})
After download, res.path returns the path like this.
I am trying to convert it to the URI to be displayed using the Image component. I tried binding the following state object to the Image component.
{
uri: res.path()
}
It did not work. That is why as a next attempt, I am trying to convert the path into URI and display the uri. How can I do that?
Try providing the path of the file where you want to download it,
const directoryFile = RNFS.ExternalStorageDirectoryPath + "/FolderName/";
RNFS.mkdir(directoryFile);
const urlDownload = input.url;
let fileName;
fileName = "filename.zip";
let dirs = directoryFile + fileName;
RNFetchBlob.config({
// response data will be saved to this path if it has access right.
path: dirs
}).fetch("GET", urlDownload, {
//some headers ..
})
.then(res => {
console.log("The file saved to ", res.path());
//RNFS.moveFile(dirs, directoryFile + fileName); // -> uncomment this line if it still does not store at your desired path
alert("File Downloaded At Folder");
})
.catch(err => {
console.log("Error: " + err);
});

how to create pdf in react-native

I want to create pdf in my app in react-native for word to pdf or html to pdf converter.I have tried all possible react-native packages but none of them give me a desired result what should I do.
Are you using nodeJS on the server? If you are, send the html to the server and use this to convert the html to a pdf.
Have you Checked react-native-pdf-lib.
It is pretty good module.
Otherwise consider server side rendering
You can generate pdf file in react native with the npm package react-native-html-to-pdf.
Steps :
Create HTML template of your pdf file you want to generate.
Install the package and install pod in ios folder with pod install
Rebuild the app in android/ios.
import RNHTMLtoPDF from 'react-native-html-to-pdf';
const createPdf = async () => {
try {
let options = {
html: '<div>Hello pdf</div>',
fileName: 'demofile',
directory: 'Downloads',
base64: true,
};
let file = await RNHTMLtoPDF.convert(options);
console.log(file);
} catch (error) {
console.log(error);
}
}
Here is the more specific answer to your problem :
import RNHTMLtoPDF from 'react-native-html-to-pdf';
const createPdf = async () => {
let h1 = "Hey Heading 1";
let h2 = "heading 2";
let para = "Something description";
// use Backtick(`) to define html for your custom dynamic content
const pdf_html = `<div>
<h1>{h1}</h1>
<h1>{h2}</h1>
<h1>{para}</h1>
</div`;
try {
let options = {
html: pdf_html,
fileName: 'demofile',
directory: 'Downloads',
base64: true,
};
let file = await RNHTMLtoPDF.convert(options);
console.log(file);
} catch (error) {
console.log(error);
}
}

How to upload file to server using react-native

I am developing a app where i need to upload an image to the server. Based on the image i get a response which i need to render?.
Can you please help me how to upload an image using react-native?.
There is file uploading built into React Native.
Example from React Native code:
var photo = {
uri: uriFromCameraRoll,
type: 'image/jpeg',
name: 'photo.jpg',
};
var body = new FormData();
body.append('authToken', 'secret');
body.append('photo', photo);
body.append('title', 'A beautiful photo!');
var xhr = new XMLHttpRequest();
xhr.open('POST', serverURL);
xhr.send(body);
My solution is using fetch API and FormData.
Tested on Android.
const file = {
uri, // e.g. 'file:///path/to/file/image123.jpg'
name, // e.g. 'image123.jpg',
type // e.g. 'image/jpg'
}
const body = new FormData()
body.append('file', file)
fetch(url, {
method: 'POST',
body
})
I wrote something like that. Check out https://github.com/kamilkp/react-native-file-transfer
I have been struggling to upload images recently on react-native. I didn't seem to get the images uploaded. This is actually because i was using the react-native-debugger and network inspect on while sending the requests. Immediately i switch off network inspect, the request were successful and the files uploaded.
I am using the example from this answer above it works for me.
This article on github about the limitations of network inspect feature may clear things for you.
Just to build on the answer by Dev1, this is a good way to upload files from react native if you also want to show upload progress. It's pure JS, so this would actually work on any Javascript file.
(Note that in step #4 you have to replace the variables inside the strings with the type and file endings. That said, you could just take those fields out.)
Here's a gist I made on Github: https://gist.github.com/nandorojo/c641c176a053a9ab43462c6da1553a1b
1. for uploading one file:
// 1. initialize request
const xhr = new XMLHttpRequest();
// 2. open request
xhr.open('POST', uploadUrl);
// 3. set up callback for request
xhr.onload = () => {
const response = JSON.parse(xhr.response);
console.log(response);
// ... do something with the successful response
};
// 4. catch for request error
xhr.onerror = e => {
console.log(e, 'upload failed');
};
// 4. catch for request timeout
xhr.ontimeout = e => {
console.log(e, 'cloudinary timeout');
};
// 4. create formData to upload
const formData = new FormData();
formData.append('file', {
uri: 'some-file-path', // this is the path to your file. see Expo ImagePicker or React Native ImagePicker
type: `${type}/${fileEnding}`, // example: image/jpg
name: `upload.${fileEnding}` // example: upload.jpg
});
// 6. upload the request
xhr.send(formData);
// 7. track upload progress
if (xhr.upload) {
// track the upload progress
xhr.upload.onprogress = ({ total, loaded }) => {
const uploadProgress = (loaded / total);
console.log(uploadProgress);
};
}
2. uploading multiple files
Assuming you have an array of files you want to upload, you'd just change #4 from the code above to look like this:
// 4. create formData to upload
const arrayOfFilesToUpload = [
// ...
];
const formData = new FormData();
arrayOfFilesToUpload.forEach(file => {
formData.append('file', {
uri: file.uri, // this is the path to your file. see Expo ImagePicker or React Native ImagePicker
type: `${type}/${fileEnding}`, // example: image/jpg
name: `upload.${fileEnding}` // example: upload.jpg
});
})
In my opinion, the best way to send the file to the server is to use react-native-fs package, so install the package
with the following command
npm install react-native-fs
then create a file called file.service.js and modify it as follow:
import { uploadFiles } from "react-native-fs";
export async function sendFileToServer(files) {
return uploadFiles({
toUrl: `http://xxx/YOUR_URL`,
files: files,
method: "POST",
headers: { Accept: "application/json" },
begin: () => {
// console.log('File Uploading Started...')
},
progress: ({ totalBytesSent, totalBytesExpectedToSend }) => {
// console.log({ totalBytesSent, totalBytesExpectedToSend })
},
})
.promise.then(({ body }) => {
// Response Here...
// const data = JSON.parse(body); => You can access to body here....
})
.catch(_ => {
// console.log('Error')
})
}
NOTE: do not forget to change the URL.
NOTE: You can use this service to send any file to the server.
then call that service like the following:
var files = [{ name: "xx", filename:"xx", filepath: "xx", filetype: "xx" }];
await sendFileToServer(files)
NOTE: each object must have name,filename,filepath,filetype
A couple of potential alternatives are available. Firstly, you could use the XHR polyfill:
http://facebook.github.io/react-native/docs/network.html
Secondly, just ask the question: how would I upload a file in Obj-C? Answer that and then you could just implement a native module to call it from JavaScript.
There's some further discussion on all of this on this Github issue.
Tom's answer didn't work for me. So I implemented a native FilePickerModule which helps me choose the file and then use the remobile's react-native-file-transfer package to upload it. FilePickerModule returns the path of the selected file (FileURL) which is used by react-native-file-transfer to upload it.
Here's the code:
var FileTransfer = require('#remobile/react-native-file-transfer');
var FilePickerModule = NativeModules.FilePickerModule;
var that = this;
var fileTransfer = new FileTransfer();
FilePickerModule.chooseFile()
.then(function(fileURL){
var options = {};
options.fileKey = 'file';
options.fileName = fileURL.substr(fileURL.lastIndexOf('/')+1);
options.mimeType = 'text/plain';
var headers = {
'X-XSRF-TOKEN':that.state.token
};
options.headers = headers;
var url = "Set the URL here" ;
fileTransfer.upload(fileURL, encodeURI(url),(result)=>
{
console.log(result);
}, (error)=>{
console.log(error);
}, options);
})
Upload Files : using expo-image-picker npm module. Here we can upload any files or images etc. The files in a device can be accessed using the launchImageLibrary method. Then access the media on that device.
import * as ImagePicker from "expo-image-picker";
const loadFile = async () => {
let result = await ImagePicker.launchImageLibraryAsync({
mediaTypes: ImagePicker.MediaTypeOptions.All,
aspect: [4, 3],
});
return <Button title="Pick an image from camera roll" onPress={loadFile} />
}
The above code used to access the files on a device.
Also, use the camera to capture the image/video to upload by using
launchCameraAsync with mediaTypeOptions to videos or photos.