GI.GdkPixbuf.Objects.PixbufLoader

The GdkPixbufLoader struct contains only private fields.

Exported types

newtype PixbufLoader

Memory-managed wrapper type.

Constructors

PixbufLoader (ManagedPtr PixbufLoader)

Instances

Eq PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

Methods

(==) :: PixbufLoader -> PixbufLoader -> Bool

(/=) :: PixbufLoader -> PixbufLoader -> Bool

IsGValue PixbufLoader

Convert PixbufLoader to and from GValue with toGValue and fromGValue.

Defined in GI.GdkPixbuf.Objects.PixbufLoader

Methods

toGValue :: PixbufLoader -> IO GValue

fromGValue :: GValue -> IO PixbufLoader

ManagedPtrNewtype PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

Methods

toManagedPtr :: PixbufLoader -> ManagedPtr PixbufLoader

TypedObject PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

Methods

glibType :: IO GType

GObject PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

HasParentTypes PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

type ParentTypes PixbufLoader

Defined in GI.GdkPixbuf.Objects.PixbufLoader

type ParentTypes PixbufLoader = '[Object]

class (GObject o, IsDescendantOf PixbufLoader o) => IsPixbufLoader o

Type class for types which can be safely cast to PixbufLoader, for instance with toPixbufLoader.

Instances

(GObject o, IsDescendantOf PixbufLoader o) => IsPixbufLoader o

Defined in GI.GdkPixbuf.Objects.PixbufLoader

toPixbufLoader :: (MonadIO m, IsPixbufLoader o) => o -> m PixbufLoader

Cast to PixbufLoader, for types for which this is known to be safe. For general casts, use castTo.

Methods

Overloaded methods

close

pixbufLoaderClose

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> m ()

(Can throw GError)

Informs a pixbuf loader that no further writes with pixbufLoaderWrite will occur, so that it can free its internal loading structures. Also, tries to parse any data that hasn't yet been parsed; if the remaining data is partial or corrupt, an error will be returned. If False is returned, error will be set to an error from the GDK_PIXBUF_ERROR or G_FILE_ERROR domains. If you're just cancelling a load rather than expecting it to be finished, passing Nothing for error to ignore it is reasonable.

Remember that this does not unref the loader, so if you plan not to use it anymore, please objectUnref it.

getAnimation

pixbufLoaderGetAnimation

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader

-> m PixbufAnimation

Returns: The PixbufAnimation that the loader is loading, or Nothing if not enough data has been read to determine the information.

Queries the PixbufAnimation that a pixbuf loader is currently creating. In general it only makes sense to call this function after the "area-prepared" signal has been emitted by the loader. If the loader doesn't have enough bytes yet (hasn't emitted the "area-prepared" signal) this function will return Nothing.

getFormat

pixbufLoaderGetFormat

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> m (Maybe PixbufFormat)

Returns: A PixbufFormat or Nothing. The return value is owned by GdkPixbuf and should not be freed.

Obtains the available information about the format of the currently loading image file.

Since: 2.2

getPixbuf

pixbufLoaderGetPixbuf

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> m (Maybe Pixbuf)

Returns: The Pixbuf that the loader is creating, or Nothing if not enough data has been read to determine how to create the image buffer.

Queries the Pixbuf that a pixbuf loader is currently creating. In general it only makes sense to call this function after the "area-prepared" signal has been emitted by the loader; this means that enough data has been read to know the size of the image that will be allocated. If the loader has not received enough data via pixbufLoaderWrite, then this function returns Nothing. The returned pixbuf will be the same in all future calls to the loader, so simply calling objectRef should be sufficient to continue using it. Additionally, if the loader is an animation, it will return the "static image" of the animation (see pixbufAnimationGetStaticImage).

new

pixbufLoaderNew

Arguments

:: (HasCallStack, MonadIO m)

=> m PixbufLoader

Returns: A newly-created pixbuf loader.

Creates a new pixbuf loader object.

newWithMimeType

pixbufLoaderNewWithMimeType

Arguments

:: (HasCallStack, MonadIO m)

=> Text

mimeType: the mime type to be loaded

-> m PixbufLoader

Returns: A newly-created pixbuf loader. (Can throw GError)

Creates a new pixbuf loader object that always attempts to parse image data as if it were an image of mime type mimeType, instead of identifying the type automatically. Useful if you want an error if the image isn't the expected mime type, for loading image formats that can't be reliably identified by looking at the data, or if the user manually forces a specific mime type.

The list of supported mime types depends on what image loaders are installed, but typically "image/png", "image/jpeg", "image/gif", "image/tiff" and "image/x-xpixmap" are among the supported mime types. To obtain the full list of supported mime types, call pixbufFormatGetMimeTypes on each of the PixbufFormat structs returned by pixbufGetFormats.

Since: 2.4

newWithType

pixbufLoaderNewWithType

Arguments

:: (HasCallStack, MonadIO m)

=> Text

imageType: name of the image format to be loaded with the image

-> m PixbufLoader

Returns: A newly-created pixbuf loader. (Can throw GError)

Creates a new pixbuf loader object that always attempts to parse image data as if it were an image of type imageType, instead of identifying the type automatically. Useful if you want an error if the image isn't the expected type, for loading image formats that can't be reliably identified by looking at the data, or if the user manually forces a specific type.

The list of supported image formats depends on what image loaders are installed, but typically "png", "jpeg", "gif", "tiff" and "xpm" are among the supported formats. To obtain the full list of supported image formats, call pixbufFormatGetName on each of the PixbufFormat structs returned by pixbufGetFormats.

setSize

pixbufLoaderSetSize

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> Int32

width: The desired width of the image being loaded.

-> Int32

height: The desired height of the image being loaded.

-> m ()

Causes the image to be scaled while it is loaded. The desired image size can be determined relative to the original size of the image by calling pixbufLoaderSetSize from a signal handler for the sizePrepared signal.

Attempts to set the desired image size are ignored after the emission of the sizePrepared signal.

Since: 2.2

write

pixbufLoaderWrite

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> ByteString

buf: Pointer to image data.

-> m ()

(Can throw GError)

This will cause a pixbuf loader to parse the next count bytes of an image. It will return True if the data was loaded successfully, and False if an error occurred. In the latter case, the loader will be closed, and will not accept further writes. If False is returned, error will be set to an error from the GDK_PIXBUF_ERROR or G_FILE_ERROR domains.

writeBytes

pixbufLoaderWriteBytes

Arguments

:: (HasCallStack, MonadIO m, IsPixbufLoader a)

=> a

loader: A pixbuf loader.

-> Bytes

buffer: The image data as a Bytes

-> m ()

(Can throw GError)

This will cause a pixbuf loader to parse a buffer inside a Bytes for an image. It will return True if the data was loaded successfully, and False if an error occurred. In the latter case, the loader will be closed, and will not accept further writes. If False is returned, error will be set to an error from the GDK_PIXBUF_ERROR or G_FILE_ERROR domains.

See also: pixbufLoaderWrite

Since: 2.30

Signals

areaPrepared

type C_PixbufLoaderAreaPreparedCallback = Ptr () -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type PixbufLoaderAreaPreparedCallback = IO ()

This signal is emitted when the pixbuf loader has allocated the pixbuf in the desired size. After this signal is emitted, applications can call pixbufLoaderGetPixbuf to fetch the partially-loaded pixbuf.

afterPixbufLoaderAreaPrepared :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderAreaPreparedCallback -> m SignalHandlerId

Connect a signal handler for the areaPrepared signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after pixbufLoader #areaPrepared callback

genClosure_PixbufLoaderAreaPrepared :: MonadIO m => PixbufLoaderAreaPreparedCallback -> m (GClosure C_PixbufLoaderAreaPreparedCallback)

Wrap the callback into a GClosure.

mk_PixbufLoaderAreaPreparedCallback :: C_PixbufLoaderAreaPreparedCallback -> IO (FunPtr C_PixbufLoaderAreaPreparedCallback)

Generate a function pointer callable from C code, from a C_PixbufLoaderAreaPreparedCallback.

noPixbufLoaderAreaPreparedCallback :: Maybe PixbufLoaderAreaPreparedCallback

A convenience synonym for Nothing :: Maybe PixbufLoaderAreaPreparedCallback.

onPixbufLoaderAreaPrepared :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderAreaPreparedCallback -> m SignalHandlerId

Connect a signal handler for the areaPrepared signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on pixbufLoader #areaPrepared callback

wrap_PixbufLoaderAreaPreparedCallback :: PixbufLoaderAreaPreparedCallback -> C_PixbufLoaderAreaPreparedCallback

Wrap a PixbufLoaderAreaPreparedCallback into a C_PixbufLoaderAreaPreparedCallback.

areaUpdated

type C_PixbufLoaderAreaUpdatedCallback = Ptr () -> Int32 -> Int32 -> Int32 -> Int32 -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type PixbufLoaderAreaUpdatedCallback

Arguments

 = Int32

x: X offset of upper-left corner of the updated area.

-> Int32

y: Y offset of upper-left corner of the updated area.

-> Int32

width: Width of updated area.

-> Int32

height: Height of updated area.

-> IO ()

This signal is emitted when a significant area of the image being loaded has been updated. Normally it means that a complete scanline has been read in, but it could be a different area as well. Applications can use this signal to know when to repaint areas of an image that is being loaded.

afterPixbufLoaderAreaUpdated :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderAreaUpdatedCallback -> m SignalHandlerId

Connect a signal handler for the areaUpdated signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after pixbufLoader #areaUpdated callback

genClosure_PixbufLoaderAreaUpdated :: MonadIO m => PixbufLoaderAreaUpdatedCallback -> m (GClosure C_PixbufLoaderAreaUpdatedCallback)

Wrap the callback into a GClosure.

mk_PixbufLoaderAreaUpdatedCallback :: C_PixbufLoaderAreaUpdatedCallback -> IO (FunPtr C_PixbufLoaderAreaUpdatedCallback)

Generate a function pointer callable from C code, from a C_PixbufLoaderAreaUpdatedCallback.

noPixbufLoaderAreaUpdatedCallback :: Maybe PixbufLoaderAreaUpdatedCallback

A convenience synonym for Nothing :: Maybe PixbufLoaderAreaUpdatedCallback.

onPixbufLoaderAreaUpdated :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderAreaUpdatedCallback -> m SignalHandlerId

Connect a signal handler for the areaUpdated signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on pixbufLoader #areaUpdated callback

wrap_PixbufLoaderAreaUpdatedCallback :: PixbufLoaderAreaUpdatedCallback -> C_PixbufLoaderAreaUpdatedCallback

Wrap a PixbufLoaderAreaUpdatedCallback into a C_PixbufLoaderAreaUpdatedCallback.

closed

type C_PixbufLoaderClosedCallback = Ptr () -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type PixbufLoaderClosedCallback = IO ()

This signal is emitted when pixbufLoaderClose is called. It can be used by different parts of an application to receive notification when an image loader is closed by the code that drives it.

afterPixbufLoaderClosed :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderClosedCallback -> m SignalHandlerId

Connect a signal handler for the closed signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after pixbufLoader #closed callback

genClosure_PixbufLoaderClosed :: MonadIO m => PixbufLoaderClosedCallback -> m (GClosure C_PixbufLoaderClosedCallback)

Wrap the callback into a GClosure.

mk_PixbufLoaderClosedCallback :: C_PixbufLoaderClosedCallback -> IO (FunPtr C_PixbufLoaderClosedCallback)

Generate a function pointer callable from C code, from a C_PixbufLoaderClosedCallback.

noPixbufLoaderClosedCallback :: Maybe PixbufLoaderClosedCallback

A convenience synonym for Nothing :: Maybe PixbufLoaderClosedCallback.

onPixbufLoaderClosed :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderClosedCallback -> m SignalHandlerId

Connect a signal handler for the closed signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on pixbufLoader #closed callback

wrap_PixbufLoaderClosedCallback :: PixbufLoaderClosedCallback -> C_PixbufLoaderClosedCallback

Wrap a PixbufLoaderClosedCallback into a C_PixbufLoaderClosedCallback.

sizePrepared

type C_PixbufLoaderSizePreparedCallback = Ptr () -> Int32 -> Int32 -> Ptr () -> IO ()

Type for the callback on the (unwrapped) C side.

type PixbufLoaderSizePreparedCallback

Arguments

 = Int32

width: the original width of the image

-> Int32

height: the original height of the image

-> IO ()

This signal is emitted when the pixbuf loader has been fed the initial amount of data that is required to figure out the size of the image that it will create. Applications can call pixbufLoaderSetSize in response to this signal to set the desired size to which the image should be scaled.

afterPixbufLoaderSizePrepared :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderSizePreparedCallback -> m SignalHandlerId

Connect a signal handler for the sizePrepared signal, to be run after the default handler. When overloading is enabled, this is equivalent to

after pixbufLoader #sizePrepared callback

genClosure_PixbufLoaderSizePrepared :: MonadIO m => PixbufLoaderSizePreparedCallback -> m (GClosure C_PixbufLoaderSizePreparedCallback)

Wrap the callback into a GClosure.

mk_PixbufLoaderSizePreparedCallback :: C_PixbufLoaderSizePreparedCallback -> IO (FunPtr C_PixbufLoaderSizePreparedCallback)

Generate a function pointer callable from C code, from a C_PixbufLoaderSizePreparedCallback.

noPixbufLoaderSizePreparedCallback :: Maybe PixbufLoaderSizePreparedCallback

A convenience synonym for Nothing :: Maybe PixbufLoaderSizePreparedCallback.

onPixbufLoaderSizePrepared :: (IsPixbufLoader a, MonadIO m) => a -> PixbufLoaderSizePreparedCallback -> m SignalHandlerId

Connect a signal handler for the sizePrepared signal, to be run before the default handler. When overloading is enabled, this is equivalent to

on pixbufLoader #sizePrepared callback

wrap_PixbufLoaderSizePreparedCallback :: PixbufLoaderSizePreparedCallback -> C_PixbufLoaderSizePreparedCallback

Wrap a PixbufLoaderSizePreparedCallback into a C_PixbufLoaderSizePreparedCallback.