ImageViewer Class Reference

A widget for displaying static images (PNG, JPEG, etc.) within a chat interface. More...

#include <image_viewer.h>

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Signals
void	imageInfoReady (int width, int height, bool has_alpha)
	Emitted after the image information (dimensions, alpha) has been successfully received from the decoder.
void	imageLoaded ()
	Emitted after the image has been successfully decoded and set in the QLabel. Can be used by parent widgets to adjust layout once the image is ready for display.

Public Member Functions
	ImageViewer (const QByteArray &image_data, QWidget *parent=nullptr)
	Constructs an InlineImageViewer widget. Initializes the UI (QLabel), creates the ImageDecoder instance, connects signals and triggers asynchronous decoding of the image data.
void	ReleaseResources ()
	Releases resources held by the ImageDecoder. Resets the shared pointer to the decoder.
QSize	sizeHint () const override
	Provides a size hint based on the original dimensions of the loaded image. Returns the actual image size once loaded, otherwise falls back to the default QFrame size hint.
	~ImageViewer () override
	Destructor. Ensures resources are released by calling ReleaseResources().

Private Slots
void	HandleError (const QString &message)
	Slot connected to the decoder's error signal. Logs the error and displays an error message in the QLabel. Sets a minimum size to ensure the error message is visible.
void	HandleImageInfo (int width, int height, bool has_alpha)
	Slot connected to the decoder's imageInfo signal. Stores the image dimensions and alpha channel information. Emits the imageInfoReady() signal.
void	HandleImageReady (const QImage &image)
	Slot connected to the decoder's imageReady signal. Stores the decoded image, sets it as the pixmap for the internal QLabel, updates the widget's geometry, and emits the imageLoaded() signal. Relies on the QLabel's setScaledContents(true) for display scaling.
void	LoadImage () const
	Initiates the image decoding process by calling Decode() on the ImageDecoder. Called asynchronously via QTimer::singleShot after the constructor finishes.

Private Attributes
std::shared_ptr< ImageDecoder >	decoder_
	Shared pointer to the ImageDecoder instance responsible for decoding.
bool	has_alpha_ = false
	Flag indicating if the image has an alpha channel. Set by HandleImageInfo.
QByteArray	image_data_
	Stores the raw image data passed in the constructor.
int	image_height_ = 0
	Original height of the image in pixels. Set by HandleImageInfo.
QLabel *	image_label_
	QLabel used to display the image. ScaledContents is enabled.
int	image_width_ = 0
	Original width of the image in pixels. Set by HandleImageInfo.
QImage	original_image_
	Stores the original, unscaled decoded image.
TranslationManager *	translator_ = nullptr
	Pointer to the translation manager for handling UI translations.

Detailed Description

A widget for displaying static images (PNG, JPEG, etc.) within a chat interface.

This class uses ImageDecoder (which relies on Qt's image loading) to decode image data. It displays the image within a QLabel, automatically scaling the content to fit the label's size while preserving an aspect ratio (due to QLabel's setScaledContents(true)). It provides signals for when the image is loaded and when its information (size, alpha) is available.

Constructor & Destructor Documentation

ImageViewer()

ImageViewer::ImageViewer ( const QByteArray & image_data, QWidget * parent = nullptr )

explicit

Constructs an InlineImageViewer widget. Initializes the UI (QLabel), creates the ImageDecoder instance, connects signals and triggers asynchronous decoding of the image data.

Parameters

image_data	The raw image data to be displayed.
parent	Optional parent widget.

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~ImageViewer()

ImageViewer::~ImageViewer ( )

inlineoverride

Destructor. Ensures resources are released by calling ReleaseResources().

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Member Function Documentation

HandleError

void ImageViewer::HandleError ( const QString & message )

privateslot

Slot connected to the decoder's error signal. Logs the error and displays an error message in the QLabel. Sets a minimum size to ensure the error message is visible.

Parameters

message

The error message from the decoder.

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HandleImageInfo

void ImageViewer::HandleImageInfo ( int width, int height, bool has_alpha )

privateslot

Slot connected to the decoder's imageInfo signal. Stores the image dimensions and alpha channel information. Emits the imageInfoReady() signal.

Parameters

width	The width of the image in pixels.
height	The height of the image in pixels.
has_alpha	True if the image has an alpha channel.

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HandleImageReady

void ImageViewer::HandleImageReady ( const QImage & image )

privateslot

Slot connected to the decoder's imageReady signal. Stores the decoded image, sets it as the pixmap for the internal QLabel, updates the widget's geometry, and emits the imageLoaded() signal. Relies on the QLabel's setScaledContents(true) for display scaling.

Parameters

image

The successfully decoded QImage.

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imageInfoReady

void ImageViewer::imageInfoReady ( int width, int height, bool has_alpha )

signal

Emitted after the image information (dimensions, alpha) has been successfully received from the decoder.

Parameters

width	The width of the image in pixels.
height	The height of the image in pixels.
has_alpha	True if the image has an alpha channel.

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imageLoaded

void ImageViewer::imageLoaded ( )

signal

Emitted after the image has been successfully decoded and set in the QLabel. Can be used by parent widgets to adjust layout once the image is ready for display.

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LoadImage

void ImageViewer::LoadImage ( ) const

privateslot

Initiates the image decoding process by calling Decode() on the ImageDecoder. Called asynchronously via QTimer::singleShot after the constructor finishes.

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ReleaseResources()

void ImageViewer::ReleaseResources

(

)

Releases resources held by the ImageDecoder. Resets the shared pointer to the decoder.

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sizeHint()

QSize ImageViewer::sizeHint ( ) const

nodiscardoverride

Provides a size hint based on the original dimensions of the loaded image. Returns the actual image size once loaded, otherwise falls back to the default QFrame size hint.

Returns

The recommended QSize for the widget (original image size).

Member Data Documentation

decoder_

std::shared_ptr<ImageDecoder> ImageViewer::decoder_

private

Shared pointer to the ImageDecoder instance responsible for decoding.

has_alpha_

bool ImageViewer::has_alpha_ = false

private

Flag indicating if the image has an alpha channel. Set by HandleImageInfo.

image_data_

QByteArray ImageViewer::image_data_

private

Stores the raw image data passed in the constructor.

image_height_

int ImageViewer::image_height_ = 0

private

Original height of the image in pixels. Set by HandleImageInfo.

image_label_

QLabel* ImageViewer::image_label_

private

QLabel used to display the image. ScaledContents is enabled.

image_width_

int ImageViewer::image_width_ = 0

private

Original width of the image in pixels. Set by HandleImageInfo.

original_image_

QImage ImageViewer::original_image_

private

Stores the original, unscaled decoded image.

translator_

TranslationManager* ImageViewer::translator_ = nullptr

private

Pointer to the translation manager for handling UI translations.

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

• src/chat/files/image/displayer/image_viewer.h
• src/chat/files/image/displayer/image_viewer.cpp