Trait gdk_pixbuf::prelude::PixbufLoaderExt[−][src]

pub trait PixbufLoaderExt: 'static {
    fn close(&self) -> Result<(), Error>;

    fn animation(&self) -> Option<PixbufAnimation>;

    fn format(&self) -> Option<PixbufFormat>;

    fn pixbuf(&self) -> Option<Pixbuf>;

    fn set_size(&self, width: i32, height: i32);

    fn write(&self, buf: &[u8]) -> Result<(), Error>;

    fn write_bytes(&self, buffer: &Bytes) -> Result<(), Error>;

    fn connect_area_prepared<F: Fn(&Self) + 'static>(
        &self, 
        f: F
    ) -> SignalHandlerId;

    fn connect_area_updated<F: Fn(&Self, i32, i32, i32, i32) + 'static>(
        &self, 
        f: F
    ) -> SignalHandlerId;

    fn connect_closed<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;

    fn connect_size_prepared<F: Fn(&Self, i32, i32) + 'static>(
        &self, 
        f: F
    ) -> SignalHandlerId;
}
Expand description

Trait containing all PixbufLoader methods.

Implementors

PixbufLoader

Required methods

Informs a pixbuf loader that no further writes with write() 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 None 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 g_object_unref() it.

Returns

true if all image data written so far was successfully passed out via the update_area signal

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 None.

Returns

The PixbufAnimation that the loader is loading, or None if not enough data has been read to determine the information.

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

Returns

A PixbufFormat or None. The return value is owned by GdkPixbuf and should not be freed.

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 write(), then this function returns None. The returned pixbuf will be the same in all future calls to the loader, so simply calling g_object_ref() should be sufficient to continue using it. Additionally, if the loader is an animation, it will return the “static image” of the animation (see PixbufAnimationExt::static_image()).

Returns

The Pixbuf that the loader is creating, or None if not enough data has been read to determine how to create the image buffer.

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 set_size() from a signal handler for the ::size-prepared signal.

Attempts to set the desired image size are ignored after the emission of the ::size-prepared signal.

width

The desired width of the image being loaded.

height

The desired height of the image being loaded.

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.

buf

Pointer to image data.

Returns

true if the write was successful, or false if the loader cannot parse the buffer.

This will cause a pixbuf loader to parse a buffer inside a glib::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: write()

buffer

The image data as a glib::Bytes

Returns

true if the write was successful, or false if the loader cannot parse the buffer.

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

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.

x

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

y

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

width

Width of updated area.

height

Height of updated area.

This signal is emitted when close() 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.

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 set_size() in response to this signal to set the desired size to which the image should be scaled.

width

the original width of the image

height

the original height of the image

Implementors