Bug 136256 Enhance the message builder
Please see the spec attached in 133995 for detail.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ImageBuilder.java
}
			catch ( Exception e )
			{
				ExceptionHandler.handle( e,
						DLG_TITLE_LOADING_FAIL,
						DLG_ERROR_MSG_LOADING_FAIL );
			}
		}
		clearPreview( );
	}
	private void clearPreview( )
	{
		previewCanvas.clear( );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#okPressed()
	 */
	protected void okPressed( )
	{
		try
		{
			switch ( selectedType )
			{
				case URI_TYPE :
					inputImage.setURI( uriEditor.getText( ).trim( ) );
					break;
				case EMBEDDED_TYPE :
					inputImage.setImageName( embeddedImageList.getSelection( )[0] );