| Version: 3.3.1

Public Member Functions | Protected Member Functions | List of all members
wxPNGHandler Class Reference
Class List by Category » Graphics Device Interface (GDI)

`#include <wx/imagpng.h>`

Inheritance diagram for wxPNGHandler:
[legend]

## Detailed Description

This is the image handler for the PNG format.

##

Library: wxCore
Category: Graphics Device Interface (GDI)

See also
  wxImage, wxImageHandler, wxInitAllImageHandlers()

## Public Member Functions
| wxPNGHandler ()
| Default constructor for wxPNGHandler. More...
virtual bool | LoadFile (wxImage *image, wxInputStream &stream, bool verbose=true, int index=-1)
| Loads an image from a stream, putting the resulting data into image. More...
virtual bool | SaveFile (wxImage *image, wxOutputStream &stream, bool verbose=true)
| Saves an image in the output stream. More...
Public Member Functions inherited from wxImageHandler
| wxImageHandler ()
| Default constructor. More...
virtual | ~wxImageHandler ()
| Destroys the wxImageHandler object. More...
bool | CanRead (wxInputStream &stream)
| Returns true if this handler supports the image format contained in the given stream. More...
bool | CanRead (const wxString &filename)
| Returns true if this handler supports the image format contained in the file with the given name. More...
const wxString & | GetExtension () const
| Gets the preferred file extension associated with this handler. More...
const wxArrayString & | GetAltExtensions () const
| Returns the other file extensions associated with this handler. More...
int | GetImageCount (wxInputStream &stream)
| If the image file contains more than one image and the image handler is capable of retrieving these individually, this function will return the number of available images. More...
const wxString & | GetMimeType () const
| Gets the MIME type associated with this handler. More...
const wxString & | GetName () const
| Gets the name of this handler. More...
wxBitmapType | GetType () const
| Gets the image type associated with this handler. More...
void | SetExtension (const wxString &extension)
| Sets the preferred file extension associated with this handler. More...
void | SetAltExtensions (const wxArrayString &extensions)
| Sets the alternative file extensions associated with this handler. More...
void | SetMimeType (const wxString &mimetype)
| Sets the handler MIME type. More...
void | SetName (const wxString &name)
| Sets the handler name. More...
void | SetType (wxBitmapType type)
| Sets the bitmap type for the handler. More...
Public Member Functions inherited from wxObject
| wxObject ()
| Default ctor; initializes to nullptr the internal reference data. More...
| wxObject (const wxObject &other)
| Copy ctor. More...
virtual | ~wxObject ()
| Destructor. More...
virtual wxClassInfo * | GetClassInfo () const
| This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar). More...
wxObjectRefData * | GetRefData () const
| Returns the wxObject::m_refData pointer, i.e. the data referenced by this object. More...
bool | IsKindOf (const wxClassInfo *info) const
| Determines whether this class is a subclass of (or the same class as) the given class. More...
bool | IsSameAs (const wxObject &obj) const
| Returns true if this object has the same data pointer as obj. More...
void | Ref (const wxObject &clone)
| Makes this object refer to the data in clone. More...
void | SetRefData (wxObjectRefData *data)
| Sets the wxObject::m_refData pointer. More...
void | UnRef ()
| Decrements the reference count in the associated data, and if it is zero, deletes the data. More...
void | UnShare ()
| This is the same of AllocExclusive() but this method is public. More...
void | operator delete (void *buf)
| The delete operator is defined for debugging versions of the library only, when the identifier `__WXDEBUG__` is defined. More...
void * | operator new (size_t size, const wxString &filename=nullptr, int lineNum=0)
| The new operator is defined for debugging versions of the library only, when the identifier `__WXDEBUG__` is defined. More...

## Protected Member Functions
virtual bool | DoCanRead (wxInputStream &stream)
| Called to test if this handler can read an image from the given stream. More...
Protected Member Functions inherited from wxImageHandler
virtual int | DoGetImageCount (wxInputStream &stream)
| Called to get the number of images available in a multi-image file type, if supported. More...
Protected Member Functions inherited from wxObject
void | AllocExclusive ()
| Ensure that this object's data is not shared with any other object. More...
virtual wxObjectRefData * | CreateRefData () const
| Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it. More...
virtual wxObjectRefData * | CloneRefData (const wxObjectRefData *data) const
| Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data. More...

## Additional Inherited Members
Static Public Member Functions inherited from wxImageHandler
static wxVersionInfo | GetLibraryVersionInfo ()
| Retrieve the version information about the image library used by this handler. More...
Protected Attributes inherited from wxObject
wxObjectRefData * | m_refData
| Pointer to an object which is the object's reference-counted data. More...

## Constructor & Destructor Documentation

## ◆ wxPNGHandler()

wxPNGHandler::wxPNGHandler | ( |  | ) |

Default constructor for wxPNGHandler.

## Member Function Documentation

## ◆ DoCanRead()

virtual bool wxPNGHandler::DoCanRead | ( | wxInputStream & | stream | ) |
| protected virtual

Called to test if this handler can read an image from the given stream.

NOTE: this function is allowed to change the current stream position since CallDoCanRead() will take care of restoring it later

Implements wxImageHandler.

## ◆ LoadFile()

virtual bool wxPNGHandler::LoadFile | ( | wxImage * | image,
|  | wxInputStream & | stream,
|  | bool | verbose = `true`,
|  | int | index = `-1`
| ) |  |
| virtual

Loads an image from a stream, putting the resulting data into image.

If the image file contains more than one image and the image handler is capable of retrieving these individually, index indicates which image to read from the stream.

Parameters

  image | The image object which is to be affected by this operation.
  stream | Opened input stream for reading image data.
  verbose | If set to true, errors reported by the image handler will produce wxLogMessages.
  index | The index of the image in the file (starting from zero).

Returns
  true if the operation succeeded, false otherwise.

See also
  wxImage::LoadFile, wxImage::SaveFile, SaveFile()

Reimplemented from wxImageHandler.

## ◆ SaveFile()

virtual bool wxPNGHandler::SaveFile | ( | wxImage * | image,
|  | wxOutputStream & | stream,
|  | bool | verbose = `true`
| ) |  |
| virtual

Saves an image in the output stream.

Parameters

  image | The image object which is to be affected by this operation.
  stream | Opened output stream for writing the data.
  verbose | If set to true, errors reported by the image handler will produce wxLogMessages.

Returns
  true if the operation succeeded, false otherwise.

See also
  wxImage::LoadFile, wxImage::SaveFile, LoadFile()

Reimplemented from wxImageHandler.