Package org.eclipse.jface.resource

Class ImageRegistry

  • public class ImageRegistry
extends Object
    An image registry maintains a mapping between symbolic image names and SWT image objects or special image descriptor objects which defer the creation of SWT image objects until they are needed.

    An image registry owns all of the image objects registered with it, and automatically disposes of them when the SWT Display that creates the images is disposed. Because of this, clients do not need to (indeed, must not attempt to) dispose of these images themselves.

    Clients may instantiate this class (it was not designed to be subclassed).

    Unlike the FontRegistry, it is an error to replace images. As a result there are no events that fire when values are changed in the registry

    Restriction:
    This class is not intended to be subclassed by clients.

    • Constructor Detail

      • ImageRegistry

        public ImageRegistry()
        Creates an empty image registry.

        There must be an SWT Display created in the current thread before calling this method.

      • ImageRegistry

        public ImageRegistry​(ResourceManager manager)
        Creates an empty image registry using the given resource manager to allocate images.
        Parameters:
        manager - the resource manager used to allocate images
        Since:
        3.1

      • ImageRegistry

        public ImageRegistry​(Display display)
        Creates an empty image registry.
        Parameters:
        display - this Display must not be null and must not be disposed in order to use this registry

    • Method Detail

      • get

        public Image get​(String key)
        Returns the image associated with the given key in this registry, or null if none.
        Parameters:
        key - the key
        Returns:
        the image, or null if none

      • getDescriptor

        public ImageDescriptor getDescriptor​(String key)
        Returns the descriptor associated with the given key in this registry, or null if none.
        Parameters:
        key - the key
        Returns:
        the descriptor, or null if none
        Since:
        2.1

      • put

        public void put​(String key,
                ImageDescriptor descriptor)
        Adds (or replaces) an image descriptor to this registry. The first time this new entry is retrieved, the image descriptor's image will be computed (via ImageDescriptor.createImage) and remembered. This method replaces an existing image descriptor associated with the given key, but fails if there is a real image associated with it.
        Parameters:
        key - the key
        descriptor - the ImageDescriptor
        Throws:
        IllegalArgumentException - if the key already exists

      • put

        public void put​(String key,
                Image image)
        Adds an image to this registry. This method fails if there is already an image or descriptor for the given key.

        Note that an image registry owns all of the image objects registered with it, and automatically disposes of them when the SWT Display is disposed. Because of this, clients must not register an image object that is managed by another object.

        Parameters:
        key - the key
        image - the image, should not be null
        Throws:
        IllegalArgumentException - if the key already exists

      • remove

        public void remove​(String key)
        Removes an image from this registry. If an SWT image was allocated, it is disposed. This method has no effect if there is no image or descriptor for the given key.
        Parameters:
        key - the key

      • dispose

        public void dispose()
        Disposes this image registry, disposing any images that were allocated for it, and clearing its entries.
        Since:
        3.1