IBarcodeGenerator class
IBarcodeGenerator class
Public interface for barcode custom generator. Implementation should be provided by user.
Remarks
Generator instance should be passed through the FieldOptions.barcode_generator property.
Methods
| Name | Description |
|---|---|
| get_barcode_image(parameters) | Generate barcode image using the set of parameters (for DisplayBarcode field). |
| get_old_barcode_image(parameters) | Generate barcode image using the set of parameters (for old-fashioned Barcode field). |
Examples
Shows how to use a barcode generator.
doc = aw.Document("in.docx")
doc.field_options.barcode_generator = CustomBarcodeGenerator()
doc.save("out.pdf")
Shows how to implement a IBarcodeGenerator.
class CustomBarcodeGenerator(aw.fields.IBarcodeGenerator):
default_qr_x_dimension_in_pixels = 4.0
default_1_dx_dimension_in_pixels = 1.0
def twips_to_pixels(self, heightInTwips, defVal):
"""Converts a height value in twips to pixels using a default DPI of 96."""
return self.twips_to_pixels(heightInTwips, 96, defVal)
def twips_to_pixels(self, heightInTwips, resolution, def_val) :
"""Converts a height value in twips to pixels based on the given resolution."""
try :
lVal = int(heightInTwips)
return (lVal / 1440.0) * resolution
except Exception as e:
return def_val
def get_rotation_angle(self, rotationAngle, defVal):
"""Gets the rotation angle in degrees based on the given rotation angle string."""
match rotationAngle:
case "0": return 0
case "1": return 270
case "2": return 180
case "3": return 90
case _ : return defVal
def get_qr_correction_level(self, errorCorrectionLevel, def_val) -> ab.generation.QRErrorLevel:
"""Converts a string representation of an error correction level to a QRErrorLevel enum value."""
match errorCorrectionLevel:
case "0": return ab.generation.QRErrorLevel.LEVEL_L
case "1": return ab.generation.QRErrorLevel.LEVEL_M
case "2": return ab.generation.QRErrorLevel.LEVEL_Q
case "3": return ab.generation.QRErrorLevel.LEVEL_H
case _ : return def_val
def get_barcode_encode_type(self, encode_type_from_word) -> ab.generation.EncodeTypes:
"""Gets the barcode encode type based on the given encode type from Word."""
match encode_type_from_word:
case "QR":
return ab.generation.EncodeTypes.QR
case "CODE128":
return ab.generation.EncodeTypes.CODE128
case "CODE39":
return ab.generation.EncodeTypes.CODE39
case "JPPOST":
return ab.generation.EncodeTypes.RM4SCC
case "EAN8":
return ab.generation.EncodeTypes.EAN8
case "JAN8":
return ab.generation.EncodeTypes.EAN8
case "EAN13":
return ab.generation.EncodeTypes.EAN13
case "JAN13":
return ab.generation.EncodeTypes.EAN13
case "UPCA":
return ab.generation.EncodeTypes.UPCA
case "UPCE":
return ab.generation.EncodeTypes.UPCE
case "CASE":
return ab.generation.EncodeTypes.ITF14
case "ITF14":
return ab.generation.EncodeTypes.ITF14
case "NW7":
return ab.generation.EncodeTypes.CODABAR
case _:
return ab.generation.EncodeTypes.NONE
def convert_color(self, input_color, def_val) -> pydraw.Color:
"""Converts a hexadecimal color string to a Color object."""
if not input_color: return def_val
try:
color = int(input_color, base=16)
return pydraw.Color.from_argb((color >> 16) & 0xFF, (color >> 8) & 0xFF, color & 0xFF)
except Exception as e:
return def_val
def scale_factor(self, scaleFactor, def_val):
"""Calculates the scale factor based on the provided string representation."""
try :
scale = int(scaleFactor)
return scale / 100.0
except Exception as e:
return def_val
def set_pos_code_style(self, gen : ab.generation.BarcodeGenerator, pos_code_style, barcode_value):
"""Sets the position code style for a barcode generator."""
match pos_code_style:
# STD default and without changes.
case "SUP2":
gen.code_text = barcode_value[:-2]
gen.parameters.barcode.supplement.supplement_data = barcode_value[-2:]
case "SUP5":
gen.code_text = barcode_value[:-5]
gen.parameters.barcode.supplement.supplement_data = barcode_value[-5:]
case "CASE":
gen.parameters.border.visible = True
gen.parameters.border.color = gen.parameters.barcode.bar_color
gen.parameters.border.DashStyle = ab.BorderDashStyle.SOLID
gen.parameters.border.Width.Pixels = gen.parameters.barcode.x_dimension.pixels * 5
def draw_error_image(self, error) -> io.BytesIO:
"""Draws a simple error image with the given error text."""
# Create a simple image with the text "error"
from PIL import Image, ImageDraw, ImageFont
img = Image.new("RGB", (100, 100), color=(255, 255, 255))
d = ImageDraw.Draw(img)
font = ImageFont.load_default()
d.text((10, 40), error, font=font, fill=(255, 0, 0))
# Save image to a bytes buffer and return raw bytes
img_byte_arr = io.BytesIO()
img.save(img_byte_arr, format="PNG")
img_byte_arr.seek(0)
return img_byte_arr
def get_barcode_image(self, parameters: aw.fields.BarcodeParameters) -> io.BytesIO:
try:
gen = ab.generation.BarcodeGenerator(self.get_barcode_encode_type(parameters.barcode_type), parameters.barcode_value)
# Set color.
gen.parameters.barcode.bar_color = self.convert_color(parameters.foreground_color, gen.parameters.barcode.bar_color)
gen.parameters.back_color = self.convert_color(parameters.background_color, gen.parameters.back_color)
# Set display or hide text.
if not parameters.display_text:
gen.parameters.barcode.code_text_parameters.location = ab.generation.CodeLocation.NONE
else:
gen.parameters.barcode.code_text_parameters.location = ab.generation.CodeLocation.BELOW
# Set QR Code error correction level.s
gen.parameters.barcode.qr.error_level = ab.generation.QRErrorLevel.LEVEL_H
if parameters.error_correction_level:
gen.parameters.barcode.qr.error_level = self.get_qr_correction_level(parameters.error_correction_level, gen.parameters.barcode.qr.qr_error_level)
# Set rotation angle.
if parameters.symbol_rotation:
gen.parameters.rotation_angle = self.get_rotation_angle(parameters.symbol_rotation, gen.parameters.rotation_angle)
# Set scaling factor.
scalingFactor = 1
if parameters.scaling_factor:
scalingFactor = self.scale_factor(parameters.scaling_factor, scalingFactor)
# Set size.
if gen.barcode_type == ab.generation.EncodeTypes.QR:
gen.parameters.barcode.x_dimension.pixels = max(1.0, round(self.default_qr_x_dimension_in_pixels * scalingFactor))
else:
gen.parameters.barcode.x_dimension.pixels = max(1.0, round(self.default_1_dx_dimension_in_pixels * scalingFactor))
# Set height.
if parameters.symbol_height:
gen.parameters.barcode.bar_height.pixels = max(5.0, round(self.twips_to_pixels(parameters.symbol_height, gen.parameters.barcode.bar_height.pixels) * scalingFactor))
# Set style of a Point-of-Sale barcode.
if parameters.pos_code_style :
self.set_pos_code_style(gen, parameters.pos_code_style, parameters.barcode_value)
img_byte_arr = io.BytesIO()
gen.save(img_byte_arr, ab.generation.BarCodeImageFormat.PNG)
img_byte_arr.seek(0)
return img_byte_arr
except Exception as e:
print("Error generating barcode: " + str(e))
return self.draw_error_image(str(e))
def get_old_barcode_image(self, parameters: aw.fields.BarcodeParameters) -> io.BytesIO:
raise NotImplementedError()
See Also
- module aspose.words.fields