React Native is a popular framework for building mobile applications using JavaScript and React.
One of the many features that React Native provides is the ability to access the device’s file system through the Document Picker component.
In this blog post, we will take a look at how to use the Document Picker component to access and select files from the device’s file system.
First, we will start by installing the react-native-document-picker package, which provides the Document Picker component. To install the package, we can run the following command in the terminal:
npm install react-native-document-pickerOnce the package is installed, we need to link it to our React Native project. We can do this by running the following command:
react-native link react-native-document-pickerNow that the package is installed and linked, we can import the Document Picker component in our React Native project. To do this, we can add the following line of code to the top of our component file:
import DocumentPicker from 'react-native-document-picker';Once the component is imported, we can use it to access and select files from the device’s file system. To do this, we can call the show() method on the Document Picker component and pass in an options object. The options object allows us to specify the types of files we want to access, such as PDFs or images.
Here is an example of how we can use the Document Picker component to select a PDF file from the device’s file system:
async selectPDF() {
try {
const result = await DocumentPicker.show({
type: 'application/pdf',
});
console.log(
result.uri,
result.type, // mime type
result.name,
result.size
);
} catch (err) {
if (DocumentPicker.isCancel(err)) {
// User cancelled the picker
} else {
throw err;
}
}
}In this example, we are calling the show() method on the Document Picker component and passing in an options object with the type property set to application/pdf. This tells the Document Picker to only show PDF files.
When a user selects a file, the show() the method will return a result object with the following properties:
uri: The URI of the selected file.type: The mime type of the selected file.name: The name of the selected file.size: The size of the selected file in bytes.
We can then use these properties to display the selected file in our React Native application.
It should also be noted that on iOS, the user will need to give permission to access their files. This can be done by adding the NSDocumentPickerUsageDescription key to the Info.plist file in the iOS project, with a string value explaining to the user why the app needs access to their files.
In conclusion, the Document Picker component in React Native provides a simple way to access and select files from the device’s file system. By specifying the types of files we want to access, we can easily allow users to select and upload files in our React Native applications.
