setTransparency method

void setTransparency(
  1. double alpha, {
  2. double? alphaBrush,
  3. PdfBlendMode mode = PdfBlendMode.normal,
})

Sets the transparency of this graphics.

//Creates a new PDF document.
PdfDocument doc = PdfDocument();
//Create PDF graphics for the page
doc.pages.add().graphics
  //Set transparancy.
  ..setTransparency(0.5, alphaBrush: 0.5, mode: PdfBlendMode.hardLight)
  ..drawString('Hello world!',
      PdfStandardFont(PdfFontFamily.helvetica, 12, style: PdfFontStyle.bold),
      brush: PdfBrushes.red, pen: PdfPens.black);
//Saves the document.
List<int> bytes = doc.save();
//Dispose the document.
doc.dispose();

Implementation

void setTransparency(double alpha,
    {double? alphaBrush, PdfBlendMode mode = PdfBlendMode.normal}) {
  if (alpha < 0 || alpha > 1) {
    ArgumentError.value(alpha, 'alpha', 'invalid alpha value');
  }
  alphaBrush ??= alpha;
  _helper.applyTransparency(alpha, alphaBrush, mode);
}