Xojo Plugin Requires Chilkat v11.7.0+

QR Code with a Text Caption

See more QR Code Examples

Demonstrates printing a line of text under a QR code, such as the order number or the address the code holds, so that a person can read it too. render.text turns the caption on and gives its value, which is printable ASCII and is drawn in a built-in font that needs no font files. The caption can go above or below the symbol, be aligned left, center or right, and be scaled. Xojo Plugin

Dim success As Boolean
success = False

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

Dim json As New Chilkat.JsonObject
success = json.UpdateString("payload.text","https://www.chilkatsoft.com/order/12345")
success = json.UpdateInt("render.moduleSize",6)

//  The caption.  It need not be the same as the text in the QR code.
success = json.UpdateBool("render.text.enabled",True)
success = json.UpdateString("render.text.value","ORDER 12345")
//  position is "below" (the default) or "above".  alignment is "center" (the default), "left" or "right".
success = json.UpdateString("render.text.position","below")
//  Each dot of the caption's font is drawn this many pixels wide.
success = json.UpdateInt("render.text.scale",3)

success = json.UpdateString("output.path","qa_output/qr_caption.png")
success = json.UpdateBool("output.overwrite",True)
success = json.UpdateString("output.return","none")

Dim fmt As New Chilkat.Formats
Dim jsonOut As New Chilkat.JsonObject
success = fmt.QrCode("generate",json,jsonOut)
If (success = False) Then
    System.DebugLog(fmt.LastErrorText)
    Return
End If

System.DebugLog("caption: " + jsonOut.StringOf("measurements[0].text"))
System.DebugLog("caption scale: " + Str(jsonOut.IntOf("measurements[0].textScale")))
System.DebugLog("height added for the caption: " + Str(jsonOut.IntOf("measurements[0].textBandPx")) + " pixels")
System.DebugLog("image: " + Str(jsonOut.IntOf("measurements[0].canvasWidth")) + " x " + Str(jsonOut.IntOf("measurements[0].canvasHeight")) + " pixels")

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

//  

//  Sample output:

//  caption: ORDER 12345
//  caption scale: 3
//  height added for the caption: 21 pixels
//  image: 222 x 243 pixels