Java Requires Chilkat v11.7.0+

Create a Wi-Fi QR Code

Demonstrates a QR code that joins a phone to a Wi-Fi network when scanned. A QR code only holds text. Phones recognize text of the form WIFI:T:;S:;P:;; and offer to join the network. T is WPA (also used for WPA2 and WPA3), WEP, or nopass for an open network, and H:true can be added for a hidden network. In the name and the password, the characters backslash, semicolon, comma, colon and double quote must each be preceded by a backslash.

Chilkat Java Downloads

Download Chilkat for Java

Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Formats;
import com.chilkatsoft.chilkat2.JsonObject;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        JsonObject json = new JsonObject();
        json.updateString("payload.text", "WIFI:T:WPA;S:Chilkat Guest;P:correct-horse-battery-staple;;");

        // Level Q, so that the code still scans when it is printed small or gets worn.
        json.updateString("encoding.qr.errorCorrection", "Q");
        json.updateInt("render.moduleSize", 8);

        // Say which network it is under the code.
        json.updateBool("render.text.enabled", true);
        json.updateString("render.text.value", "Wi-Fi: Chilkat Guest");
        json.updateInt("render.text.scale", 2);

        json.updateString("output.path", "qa_output/qr_wifi.png");
        json.updateBool("output.overwrite", true);
        json.updateString("output.return", "none");

        Formats fmt = new Formats();
        JsonObject jsonOut = new JsonObject();
        try {
            fmt.qrCode("generate", json, jsonOut);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("file: " + jsonOut.stringOf("outputs[0].path"));
        System.out.println("QR version: " + jsonOut.intOf("symbols[0].selectedEncoding.version"));
        System.out.println("image: " + jsonOut.intOf("outputs[0].width") + " x " + jsonOut.intOf("outputs[0].height") + " pixels");

        // The image written to qa_output/qr_wifi.png:

        // 

        // Sample output:

        // file: qa_output/qr_wifi.png
        // QR version: 5
        // image: 360 x 374 pixels
    }
}