[Digikam-devel] How to apply changes in digikams IPTC settings to all tagged photos?

[Marcel Wiesweg]

> A patch to do it is here :
>
> http://digikam3rdparty.free.fr/misc.tarballs/commentstagsprogress.patch
>
> This one include to run a progress bar on the top of sidebar when :
>
> - Apply button is pressed
> - More button options are used.
>
> TODO : handle Tags drag & drop.
>
> ...but, there is a problem with this solution...
>
> We need to fix all DMetadata call everywhere in digiKam to used MetadataHub
> instead. This not yet done for example with all Drag and drop actions from
> others sidebar (TagsFilter for example)
>
> ... and we need to give a progress feedback everywhere, because metadata to
> write in pictures can take a while with huge selection.
>
> I think than an ultimate solution is to use a _Status Bar_ on the bottom of
> Album gui.
>
> What do you think about ?

Yes the progress bar in the status bar is better. Especially if we also write 
metadata when assigning with drag and drop, the status bar is the right 
place.

It seems we have once again opened a box which proves to be much larger than 
it appeared ;-)

For the ultimate solution, I have two more requirements:

1) When a user assigns tag A to 1500 images it takes some time to write the 
DMetadata. After that, he wants to assign another tag to the same images. 
Again, it takes considerable time. This means users will wish to temporally 
disable writing.
An elegant solution is to implement (2).

2) Do the whole thing multithreaded. This solves (1).
Implementing this when we have ported to KDE4/Qt4 will be much easier. So I 
would prefer to delay this.

For now, the solution can be:
- the right side bar emits progress signals (similar to the methods you added 
to NavigateBarTab)
- DigikamView connects to these signals, manages the progress bar
- if we write metadata after drag&drop/context menu assignment, the 
AlbumIconView can emit the same signals

Marcel

>
> Nota : Image editor is not affected here because it work only on a single
> image.