PrintContext

open class PrintContext : GLibObject.Object, PrintContextProtocol

A GtkPrintContext encapsulates context information that is required when drawing pages for printing.

This includes the cairo context and important parameters like page size and resolution. It also lets you easily create [classPango.Layout] and [classPango.Context] objects that match the font metrics of the cairo surface.

GtkPrintContext objects get passed to the [signalGtk.PrintOperation::begin-print], [signalGtk.PrintOperation::end-print], [signalGtk.PrintOperation::request-page-setup] and [signalGtk.PrintOperation::draw-page] signals on the [classGtk.PrintOperation] object.

Using GtkPrintContext in a draw-page callback

static void
draw_page (GtkPrintOperation *operation,
           GtkPrintContext   *context,
           int                page_nr)
{
  cairo_t *cr;
  PangoLayout *layout;
  PangoFontDescription *desc;

  cr = gtk_print_context_get_cairo_context (context);

  // Draw a red rectangle, as wide as the paper (inside the margins)
  cairo_set_source_rgb (cr, 1.0, 0, 0);
  cairo_rectangle (cr, 0, 0, gtk_print_context_get_width (context), 50);

  cairo_fill (cr);

  // Draw some lines
  cairo_move_to (cr, 20, 10);
  cairo_line_to (cr, 40, 20);
  cairo_arc (cr, 60, 60, 20, 0, M_PI);
  cairo_line_to (cr, 80, 20);

  cairo_set_source_rgb (cr, 0, 0, 0);
  cairo_set_line_width (cr, 5);
  cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
  cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);

  cairo_stroke (cr);

  // Draw some text
  layout = gtk_print_context_create_pango_layout (context);
  pango_layout_set_text (layout, "Hello World! Printing is easy", -1);
  desc = pango_font_description_from_string ("sans 28");
  pango_layout_set_font_description (layout, desc);
  pango_font_description_free (desc);

  cairo_move_to (cr, 30, 20);
  pango_cairo_layout_path (cr, layout);

  // Font Outline
  cairo_set_source_rgb (cr, 0.93, 1.0, 0.47);
  cairo_set_line_width (cr, 0.5);
  cairo_stroke_preserve (cr);

  // Font Fill
  cairo_set_source_rgb (cr, 0, 0.0, 1.0);
  cairo_fill (cr);

  g_object_unref (layout);
}

The PrintContext type acts as a reference-counted owner of an underlying GtkPrintContext instance. It provides the methods that can operate on this data type through PrintContextProtocol conformance. Use PrintContext as a strong reference or owner of a GtkPrintContext instance.

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  • Designated initialiser from the underlying `C` data type.

    This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
public init(_ op: UnsafeMutablePointer<GtkPrintContext>)

    Parameters

    op

    pointer to the underlying object
    Show on GitHub

  • Designated initialiser from a constant pointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
public init(_ op: UnsafePointer<GtkPrintContext>)

    Parameters

    op

    pointer to the underlying object
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  • Optional initialiser from a non-mutating gpointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
override public init!(gpointer op: gpointer?)

    Parameters

    op

    gpointer to the underlying object
    Show on GitHub

  • Optional initialiser from a non-mutating gconstpointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
override public init!(gconstpointer op: gconstpointer?)

    Parameters

    op

    pointer to the underlying object
    Show on GitHub

  • Optional initialiser from a constant pointer to the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
public init!(_ op: UnsafePointer<GtkPrintContext>?)

    Parameters

    op

    pointer to the underlying object
    Show on GitHub

  • Optional initialiser from the underlying C data type. This creates an instance without performing an unbalanced retain i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
public init!(_ op: UnsafeMutablePointer<GtkPrintContext>?)

    Parameters

    op

    pointer to the underlying object
    Show on GitHub

  • Designated initialiser from the underlying C data type. Will retain GtkPrintContext. i.e., ownership is transferred to the PrintContext instance.

    Declaration

    Swift

    @inlinable
public init(retaining op: UnsafeMutablePointer<GtkPrintContext>)

    Parameters

    op

    pointer to the underlying object
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  • Reference intialiser for a related type that implements PrintContextProtocol Will retain GtkPrintContext.

    Declaration

    Swift

    @inlinable
public init<T>(printContext other: T) where T : PrintContextProtocol

    Parameters

    other

    an instance of a related type that implements PrintContextProtocol
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  • Unsafe typed initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init<T>(cPointer p: UnsafeMutablePointer<T>)

    Parameters

    cPointer

    pointer to the underlying object
    Show on GitHub

  • Unsafe typed, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init<T>(retainingCPointer cPointer: UnsafeMutablePointer<T>)

    Parameters

    cPointer

    pointer to the underlying object
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  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init(raw p: UnsafeRawPointer)

    Parameters

    p

    raw pointer to the underlying object
    Show on GitHub

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init(retainingRaw raw: UnsafeRawPointer)
    Show on GitHub

  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
public required init(raw p: UnsafeMutableRawPointer)

    Parameters

    p

    mutable raw pointer to the underlying object
    Show on GitHub

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
required public init(retainingRaw raw: UnsafeMutableRawPointer)

    Parameters

    raw

    mutable raw pointer to the underlying object
    Show on GitHub

  • Unsafe untyped initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init(opaquePointer p: OpaquePointer)

    Parameters

    p

    opaque pointer to the underlying object
    Show on GitHub

  • Unsafe untyped, retaining initialiser. Do not use unless you know the underlying data type the pointer points to conforms to PrintContextProtocol.

    Declaration

    Swift

    @inlinable
override public init(retainingOpaquePointer p: OpaquePointer)

    Parameters

    p

    opaque pointer to the underlying object
    Show on GitHub