org.eclipse.swt.graphics
Class Image

java.lang.Object
  org.eclipse.swt.graphics.Resource
      org.eclipse.swt.graphics.Image

public final class Image

extends Resource

Instances of this class are graphics which have been prepared for display on a specific device. That is, they are to display on widgets with, for example, Button.setImage().

If loaded from a file format that supports it, an Image may have transparency, meaning that certain pixels are specified as being transparent when drawn. Examples of file formats that support transparency are GIF and PNG.

Note: Even though constructors are provided here, it is recommended to create images by using one of the getImage methods in class Graphics. These factory methods share images among all sessions. Creating images via constructors carelessly may lead to bad performance and/or unnecessary memory consumption.

See Also:

Graphics.getImage(String), Graphics.getImage(String, ClassLoader), Graphics.getImage(String, java.io.InputStream)

Field Summary

String

resourceName IMPORTANT: This field is not part of the SWT public API.

Constructor Summary

Image(Device device, ImageData imageData)
Constructs an instance of this class from the given ImageData.

Image(Device device, Image srcImage, int flag)
Constructs a new instance of this class based on the provided image, with an appearance that varies depending on the value of the flag.

Image(Device device, InputStream stream)
Constructs an instance of this class by loading its representation from the specified input stream.

Image(Device device, String fileName)
Constructs an instance of this class by loading its representation from the file with the specified name.

Method Summary

Rectangle	getBounds() Returns the bounds of the receiver.
ImageData	getImageData() Returns an ImageData based on the receiver Modifications made to this ImageData will not affect the Image.

Methods inherited from class org.eclipse.swt.graphics.Resource

dispose, getDevice, isDisposed

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

resourceName

public String resourceName

IMPORTANT: This field is not part of the SWT public API. It is marked public only so that it can be shared within the packages provided by SWT. It is not available on all platforms and should never be accessed from application code.

Constructor Detail

Image

public Image(Device device,
             InputStream stream)

Constructs an instance of this class by loading its representation from the specified input stream. Throws an error if an error occurs while loading the image, or if the result is an image of an unsupported type. Application code is still responsible for closing the input stream.

This constructor is provided for convenience when loading a single image only. If the stream contains multiple images, only the first one will be loaded. To load multiple images, use ImageLoader.load().

This constructor may be used to load a resource as follows:

     static Image loadImage (Display display, Class clazz, String string) {
          InputStream stream = clazz.getResourceAsStream (string);
          if (stream == null) return null;
          Image image = null;
          try {
               image = new Image (display, stream);
          } catch (SWTException ex) {
          } finally {
               try {
                    stream.close ();
               } catch (IOException ex) {}
          }
          return image;
     }
 

Note, this constructor is provided for convenience when single-sourcing code with SWT. For RWT, the recommended way to create images is to use one of the Graphics#getImage() methods.

Parameters:

device - the device on which to create the image

stream - the input stream to load the image from

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if device is null and there is no current device
• ERROR_NULL_ARGUMENT - if the stream is null

SWTException -

• ERROR_IO - if an IO error occurs while reading from the stream
• ERROR_INVALID_IMAGE - if the image stream contains invalid data
• ERROR_UNSUPPORTED_DEPTH - if the image stream describes an image with an unsupported depth
• ERROR_UNSUPPORTED_FORMAT - if the image stream contains an unrecognized format

SWTError -

• ERROR_NO_HANDLES if a handle could not be obtained for image creation

Since:

1.3

See Also:

Graphics.getImage(String), Graphics.getImage(String, ClassLoader), Graphics.getImage(String, java.io.InputStream)

Image

public Image(Device device,
             String fileName)

Constructs an instance of this class by loading its representation from the file with the specified name. Throws an error if an error occurs while loading the image, or if the result is an image of an unsupported type.

This constructor is provided for convenience when loading a single image only. If the specified file contains multiple images, only the first one will be used.

Note, this constructor is provided for convenience when single-sourcing code with SWT. For RWT, the recommended way to create images is to use one of the Graphics#getImage() methods.

Parameters:

device - the device on which to create the image

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if device is null and there is no current device
• ERROR_NULL_ARGUMENT - if the file name is null

SWTException -

• ERROR_IO - if an IO error occurs while reading from the file
• ERROR_INVALID_IMAGE - if the image file contains invalid data
• ERROR_UNSUPPORTED_DEPTH - if the image file describes an image with an unsupported depth
• ERROR_UNSUPPORTED_FORMAT - if the image file contains an unrecognized format

SWTError -

• ERROR_NO_HANDLES if a handle could not be obtained for image creation

Since:

1.3

See Also:

Graphics.getImage(String), Graphics.getImage(String, ClassLoader), Graphics.getImage(String, java.io.InputStream)

Image

public Image(Device device,
             Image srcImage,
             int flag)

Constructs a new instance of this class based on the provided image, with an appearance that varies depending on the value of the flag. The possible flag values are:

SWT.IMAGE_COPY

the result is an identical copy of srcImage

SWT#IMAGE_DISABLE

the result is a copy of srcImage which has a disabled look

SWT#IMAGE_GRAY

the result is a copy of srcImage which has a gray scale look

Parameters:

device - the device on which to create the image

srcImage - the image to use as the source

flag - the style, either IMAGE_COPY, IMAGE_DISABLE or IMAGE_GRAY

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if device is null and there is no current device
• ERROR_NULL_ARGUMENT - if srcImage is null
• ERROR_INVALID_ARGUMENT - if the flag is not one of IMAGE_COPY, IMAGE_DISABLE or IMAGE_GRAY
• ERROR_INVALID_ARGUMENT - if the image has been disposed

SWTException -

• ERROR_INVALID_IMAGE - if the image is not a bitmap or an icon, or is otherwise in an invalid state
• ERROR_UNSUPPORTED_DEPTH - if the depth of the image is not supported

SWTError -

• ERROR_NO_HANDLES if a handle could not be obtained for image creation

Since:

1.3

Image

public Image(Device device,
             ImageData imageData)

Constructs an instance of this class from the given ImageData.

Parameters:

device - the device on which to create the image

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if device is null and there is no current device
• ERROR_NULL_ARGUMENT - if the image data is null

SWTException -

• ERROR_UNSUPPORTED_DEPTH - if the depth of the ImageData is not supported

Since:

1.3

Method Detail

getBounds

public Rectangle getBounds()

Returns the bounds of the receiver. The rectangle will always have x and y values of 0, and the width and height of the image.

Returns:

a rectangle specifying the image's bounds

Throws:

SWTException -

• ERROR_INVALID_IMAGE - if the image is not a bitmap or an icon

getImageData

public ImageData getImageData()

Returns an ImageData based on the receiver Modifications made to this ImageData will not affect the Image.

Returns:

an ImageData containing the image's data and attributes

Throws:

SWTException -

• ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
• ERROR_INVALID_IMAGE - if the image is not a bitmap or an icon

Since:

1.3

See Also:

ImageData