Icon Class Reference

#include <Pt/Forms/Icon.h>

Represents an image at one or more logical sizes. More...

Public Member Functions
	Icon ()
	Creates an empty icon with a built-in provider.
	Icon (const Icon &icon)
	Shares images with icon until addImage() or clear().
	Icon (IconProvider &provider)
	Attaches provider. The icon does not own it.
	~Icon ()
	Releases this copy. More...
Icon &	operator= (const Icon &icon)
	Shares images with icon until addImage() or clear().
bool	empty () const
	Returns true when no images are registered.
void	clear ()
	Removes all images from this icon. More...
void	addImage (const Gfx::Image &image)
	Registers image using its pixel size as the key. More...
void	addImage (const Gfx::SizeF &size, const Gfx::Image &image)
	Registers image at logical size size. More...
void	addImage (const Gfx::SizeF &size, const System::Path &path)
	Registers a file path at logical size size. More...
void	addImage (double width, double height, const System::Path &path)
	Registers a file path at width by height.
const Gfx::Image &	getImage (const Gfx::SizeF &area) const
	Returns an image for the requested area. More...
Gfx::SizeF	minimumSize () const
	Returns the smallest registered size, or an empty size.
Gfx::SizeF	maximumSize () const
	Returns the largest registered size, or an empty size.

Detailed Description

An Icon is not a Widget. It supplies images to controls, which request an image for a layout area with getImage(). Label, PushButton, Panel, and list items accept an Icon through setIcon().

A default icon uses a built-in provider. Icon(IconProvider&) attaches a caller-owned provider that must outlive the icon. Copies share the same implementation until addImage() or clear() changes one copy.

addImage() registers an image or file path at a logical size. Passing only an image uses its pixel size as the key. The logical size may differ from the pixel size. Images registered by path load as PNG on first use through Application::loadImage(). A missing path produces an empty image.

getImage() returns the registered image for a requested area. The built-in provider selects the largest image that fits entirely in that area. An empty icon produces an empty image. minimumSize() and maximumSize() return the smallest and largest registered keys.

Pt::Forms::Icon icon;
icon.addImage(Pt::Gfx::SizeF(16, 16), Pt::System::Path("app-16.png"));
icon.addImage(Pt::Gfx::SizeF(32, 32), Pt::System::Path("app-32.png"));
 
Pt::Forms::Label label;
label.setIcon(icon, Pt::Gfx::SizeF(16, 16));
label.setText("Hello");

Constructor & Destructor Documentation

~Icon()

~Icon

(

)

The last copy destroys the shared images and detaches from a custom provider.

Member Function Documentation

clear()

void clear

(

)

Copies of this icon are not affected.

addImage() [1/3]

void addImage

(

const Gfx::Image &

image

)

Copies of this icon are not affected.

addImage() [2/3]

void addImage	(	const Gfx::SizeF &	size,
		const Gfx::Image &	image
	)

Copies of this icon are not affected. size may differ from the image pixel size.

addImage() [3/3]

void addImage	(	const Gfx::SizeF &	size,
		const System::Path &	path
	)

The image loads on first use. Copies of this icon are not affected.

getImage()

const Gfx::Image& getImage

(

const Gfx::SizeF &

area

)

const

May load a path image on first use.