ImageButton can't update image resource

[pauliaia]

I can add image in imagebutton src
but it can't be update
for example:
I put the image resource in layout.xml,and I set image resource in java ,it will not update button image

[NicoMich]

The same... no way to update view's background color or ImageView background drawable ressource...
It would be very nice to be able to do that...