DynaPDF Manual - Page 160

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Function Reference

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patterns are applied like a mask in the user defined color. The color must be defined in the current

color space.

To disable a pattern just change the current fill or stroke color with SetFillColor(), SetStrokeColor()

or SetColors().

Return values:

If the function succeeds the return value is 1. If the function fails the return value is 0.

Example (Delphi):

implementation

{$R *.dfm}

uses dynapdf; // include the unit dynapdf.pas

// First we define our callback function that is called if an

// error occurred. Note: The calling convention is stdcall!

function ErrProc(const Data: Pointer; ErrCode: Integer; const ErrMessage:

PAnsiChar; ErrType: Integer): Integer; stdcall;

var s: String;

begin

s := Format('%s'#13'Abort processing?', [ErrMessage]);

if MessageDlg(s, mtError, [mbYes, mbNo], 0) = mrYes then

Result := -1 // break processing

else

Result := 0; // try to continue

end;

procedure TForm1.Button1Click(Sender: TObject);

var pdf: TPDF; pat: Integer; cw, h: Single;

begin

pdf := nil;

try

pdf := TPDF.Create;

// Set the error callback first. No need to check return values.

pdf.SetOnErrorProc(nil, @ErrProc);

pdf.SetDocInfoA(diAuthor, 'Jens Boschulte');

pdf.SetDocInfoA(diCreator, 'Delphi sample project');

pdf.SetDocInfoA(diSubject, 'How to use patterns');

pdf.SetDocInfoA(diTitle, 'Vector graphics');

pdf.SetViewerPreferences(vpDisplayDocTitle, avNone);

pdf.CreateNewPDFA('c:\dout.pdf');

pdf.Append;

// create a colored tiling pattern

pat := pdf.BeginPattern(ptColored, ttFastConstSpacing, 20, 20);

pdf.SetFontA('ZapfDingbats', fsNone, 12, false, cp1252);

h := pdf.GetAscent;

cw := pdf. GetTextWidthA(#171);

pdf.SetFillColor(clRed);

pdf.WriteTextA(0, 0, #171);

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