Using a Quick Response (QR) code to link to content

A QR code is a type of two-dimensional barcode that contains encoded information. Figure 14-7 shows an example of a QR code.

Figure 14-7

A QR code

QR codes are used by a wide range of applications targeted to mobile-phone users. QR codes can store URLs, business card information, or any kind of text. Use a QR code in a report to provide contact information or links to other reports. Mobile-phone users who have a QR code reader on their phone can scan the image of a QR code to display the contact information or open a report.

Actuate BIRT Designer includes a QR code generator, ZXing, for generating QR codes. To insert a QR code in a report, insert an image element to display the QR code. In the image’s onCreate or onRender event, write code to dynamically create the QR code. Listing 14-1 shows a code example that creates a QR code that when scanned opens a report, qrreport.rptdesign, on an Actuate BIRT iServer.

Listing 14-1

Code to create a QR code that opens a report

var size = 350; // image width and height in pixels

var bgnd = new Packages.java.awt.Color(1.0, 1.0, 1.0); // white background

var fgnd = new Packages.java.awt.Color(0, 0, 0); // black foreground

 

// Report URL to encode.

var message = "http://athena:8910/iportal/executereport.do?__executablename=/qrreport.rptdesign&invokeSubmit=true;"

 

var writer = new Packages.com.google.zxing.qrcode.QRCodeWriter();

var matrix = writer.encode(message, Packages.com.google.zxing.BarcodeFormat.QR_CODE, size, size);

 

var bi = new Packages.java.awt.image.BufferedImage(size, size, Packages.java.awt.image.BufferedImage.TYPE_INT_RGB);

var g = bi.getGraphics();

g.setColor(bgnd);

g.fillRect(0,0,size,size);

g.setColor(fgnd);

for (var y = 0; y < size; y++) {

  for (var x = 0; x < size; x++) {

    if (matrix.get(x, y)) {

      g.fillRect(x, y, 1, 1);

    }

  }

}

 

baos = new Packages.java.io.ByteArrayOutputStream();

Packages.javax.imageio.ImageIO.write(bi, "png", baos);

QR codes support up to 4,296 characters. The higher the number of characters, the higher the resolution of the QR code. Note, however, that low-resolution mobile phone cameras might not be able to read high-resolution codes.

Copyright Actuate Corporation 2012