[ImageJ-devel] Plugin that Extends ImagePlus

[Johannes Schindelin]

Hi,

On Sat, 28 Aug 2010, Grant B. Harris wrote:

>  I'm curious as to why HandleExtraFileTypes (and some other reader plugins)
> extend ImagePlus.  This seems rather un-object-oriented... No?  Seems like a
> 'plugin' should operate on or create an ImagePlus.  I'm sure there is a
> history I am unaware of, so perhaps someone can fill me in.

I agree, it is clunky. But at the moment, it is the only way you can 
implement and image opener that is batch-mode friendly. IOW if you call 
IJ.openImage(), the result will be the image opened by your plugin, but 
_only_ if the plugin itself implements ImagePlus.

The reason is the design of the plugin architecture, which does not allow 
for return values.

(IOW the very same thing you and me addressed by "output parameters")

Ciao,
Johanns