📄 gtkprintcontext.sgml
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<!-- ##### SECTION Title ##### -->GtkPrintContext<!-- ##### SECTION Short_Description ##### -->Encapsulates context for drawing pages<!-- ##### SECTION Long_Description ##### --><para>A GtkPrintContext encapsulates context information that is required whendrawing pages for printing, such as the cairo context and important parameters like page size and resolution. It also lets you easilycreate #PangoLayout and #PangoContext objects that match the font metrics of the cairo surface.</para><para>GtkPrintContext objects gets passed to the ::begin-print, ::end-print, ::request-page-setup and ::draw-page signals on the #GtkPrintOperation.</para><example><title>Using GtkPrintContext in a ::draw-page callback</title><programlisting>static voiddraw_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_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);}</programlisting></example><para>Printing support was added in GTK+ 2.10.</para><!-- ##### SECTION See_Also ##### --><para></para><!-- ##### SECTION Stability_Level ##### --><!-- ##### STRUCT GtkPrintContext ##### --><para></para><!-- ##### FUNCTION gtk_print_context_get_cairo_context ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_set_cairo_context ##### --><para></para>@context: @cr: @dpi_x: @dpi_y: <!-- ##### FUNCTION gtk_print_context_get_page_setup ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_get_width ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_get_height ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_get_dpi_x ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_get_dpi_y ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_get_pango_fontmap ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_create_pango_context ##### --><para></para>@context: @Returns: <!-- ##### FUNCTION gtk_print_context_create_pango_layout ##### --><para></para>@context: @Returns:
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