cdc::ui::ImageView Class Reference

Full-screen viewer for a decoded PNG/JPEG, dithered to the e-paper. More...

#include <ImageView.h>

Inheritance diagram for cdc::ui::ImageView:

Public Member Functions
void	init (const char *title, const uint8_t *data, size_t len)
	Decodes and lays out an image.
void	render (bool partial) override
InputResult	onKey (char key) override
void	onExit () override
const char *	getName () const override
const char *	getFooterHint () const override
hal::RefreshMode	preferredEnterRefresh () const override
	Dithered images ghost badly over prior content; demand a clean base.
Public Member Functions inherited from cdc::ui::ViewBase
virtual	~ViewBase ()=default
void	onEnter (void *context) override
void	onExit () override
void	onResume () override
void	onPause () override
void	setLifecycleHooks (void(*onHide)(void *), void(*onShow)(void *), void *userData) override
bool	needsRender () const override
void	markDirty () override
void	clearDirty () override
void	setFooterHint (const char *hint) override
const char *	getFooterHint () const override
Public Member Functions inherited from cdc::ui::IView
virtual	~IView ()=default
virtual bool	prefersLightRefresh () const
virtual InputResult	onLongPress (char key)
virtual void	onTick (uint32_t nowMs)

Static Public Attributes
static constexpr uint32_t	MAX_PIXELS = 1048576
	~1 megapixel cap.

Additional Inherited Members
Protected Member Functions inherited from cdc::ui::ViewBase
void	setTitle (const char *title)
const char *	getTitle () const
Protected Attributes inherited from cdc::ui::ViewBase
bool	dirty_ = true
const char *	title_ = nullptr
const char *	customFooter_ = nullptr
void(*	onHide_ )(void *) = nullptr
void(*	onShow_ )(void *) = nullptr
void *	lifecycleUserData_ = nullptr

Detailed Description

Full-screen viewer for a decoded PNG/JPEG, dithered to the e-paper.

Decodes on init into two 1-bit bitmaps held in PSRAM: one scaled to fit the screen (default view) and one at native resolution for an actual-size pan mode. Decode failures show a readable message instead of crashing.

Keys: 5 = toggle fit/actual, 2/4/6/8 = pan (actual mode), N = back.

Definition at line 21 of file ImageView.h.

Member Function Documentation

getFooterHint()

const char * cdc::ui::ImageView::getFooterHint ( ) const

overridevirtual

Get footer hint text (e.g., "[Y] OK [N] Back") Return nullptr for no footer

Reimplemented from cdc::ui::IView.

Definition at line 126 of file ImageView.cpp.

References cdc::ui::tr().

Referenced by render().

getName()

const char * cdc::ui::ImageView::getName ( ) const

inlineoverridevirtual

Get view name for debugging

Implements cdc::ui::IView.

Definition at line 36 of file ImageView.h.

init()

void cdc::ui::ImageView::init	(	const char *	title,
		const uint8_t *	data,
		size_t	len )

Decodes and lays out an image.

Parameters

title	Header/footer title (CP437 file name).
data	Encoded image bytes (PNG or JPEG).
len	Byte length.

Definition at line 31 of file ImageView.cpp.

References cdc::ui::ViewBase::dirty_, cdc::ui::display, FOOTER_HEIGHT, cdc::hal::getDisplayInstance(), LOG_D, MAX_PIXELS, cdc::core::psramAlloc(), and cdc::ui::TAG.

onExit()

void cdc::ui::ImageView::onExit ( )

overridevirtual

Called when view is being removed from stack

Implements cdc::ui::IView.

Definition at line 105 of file ImageView.cpp.

onKey()

InputResult cdc::ui::ImageView::onKey ( char key )

overridevirtual

Handle key press

Parameters

key	Key character ('0'-'9', 'Y', 'N', etc.)

Returns

Input result

Implements cdc::ui::IView.

Definition at line 130 of file ImageView.cpp.

References cdc::ui::CONSUMED, cdc::ui::ViewBase::dirty_, cdc::ui::IGNORED, cdc::ui::KEY_DOWN, cdc::ui::KEY_NO, cdc::ui::KEY_SELECT, cdc::ui::KEY_UP, and cdc::ui::REQUEST_POP.

preferredEnterRefresh()

hal::RefreshMode cdc::ui::ImageView::preferredEnterRefresh ( ) const

inlineoverridevirtual

Dithered images ghost badly over prior content; demand a clean base.

Reimplemented from cdc::ui::IView.

Definition at line 40 of file ImageView.h.

References cdc::hal::FULL.

render()

void cdc::ui::ImageView::render ( bool partial )

overridevirtual

Render view content to display buffer

Parameters

partial

True for partial update, false for full refresh

Implements cdc::ui::IView.

Definition at line 158 of file ImageView.cpp.

References cdc::ui::ViewBase::dirty_, cdc::ui::display, cdc::ui::render::drawFooterBar(), FOOTER_HEIGHT, cdc::hal::getDisplayInstance(), getFooterHint(), cdc::ui::render::printText(), and cdc::ui::tr().

Member Data Documentation

MAX_PIXELS

uint32_t cdc::ui::ImageView::MAX_PIXELS = 1048576

staticconstexpr

~1 megapixel cap.

Definition at line 23 of file ImageView.h.

Referenced by init().

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The documentation for this class was generated from the following files:

• components/cdc_views/include/cdc_views/ImageView.h
• components/cdc_views/src/ImageView.cpp