Renderer Class Reference

#include <Pt/Forms/Renderer.h>

Provides cloneable drawing for one control family. More...

Inherits Style::Facet.

Inherited by ButtonRenderer, CheckBoxRenderer, ComboBoxRenderer, LineEditRenderer, ListBoxRenderer, ListItemRenderer, PanelRenderer, ProgressBarRenderer, ScrollBarRenderer, SliderRenderer, SpinBoxRenderer, and TabViewRenderer.

Public Member Functions
	Renderer (const std::type_info &ti, std::size_t refs=0)
	Constructor.
Renderer *	create () const
	Creates a new instance with a reference count of 0.
const std::type_info &	typeId () const
	Returns the dynamic type used as the registry key.
void	ref ()
	Adds one reference.
std::size_t	unref ()
	Removes one reference and returns the remaining count.
void	reset (const StyleOptions &options)
	Resets this facet with options.

Protected Member Functions
virtual Renderer *	onCreate () const =0
	Creates a new renderer of the same concrete type.
virtual void	onReset (const StyleOptions &)
	Resets this facet with options.

Detailed Description

A Renderer is a Style::Facet that can clone itself. Shared instances remain in Style. Use reset() to apply application options. Use create() to allocate a new instance with a reference count of 0. FacetPtr and Style::set() take their own references.

Named measure, layout, and render methods belong on derived renderer types. Use Facet::onReset() to read style options and store drawing state for those methods.

A renderer may store a Painter. That painter keeps its brush, pen, font, clip, and composition after begin(). onReset() assigns the default attributes. A render method that changes them assigns the defaults again before it returns.

Derive a renderer for a control family and register it on a Style.

Member Function Documentation

onReset()

virtual void onReset ( const StyleOptions & )

protectedvirtualinherited

Resolves tokens from options and stores the painter and metric state used later by measure, layout, and render. Shared facets are reset when the application applies global options.

Reimplemented in ButtonRenderer, CheckBoxRenderer, ComboBoxRenderer, LineEditRenderer, ListBoxRenderer, ListItemRenderer, PanelRenderer, ProgressBarRenderer, ScrollBarRenderer, SliderRenderer, SpinBoxRenderer, and TabViewRenderer.