Changing more materials of objects

I have a question - I want to change at the same time the Alpha of Material of 3 objects. I joined these objects (Ctrl + J) and I tried to change the properties. I get result for one Material only. Please help.

This is the .blend file:


What’s the meaning of this? You’re trying to edit 3 materials at the same time? Only a script could do that. Or do you want to animate the alpha value?

You cannot change the setting for multiple materials the way you are trying

You can use a simple script–-change-settings-the-fast-way/
You could use material nodes. Have a base material which you adjust and that changes all the other material that use that base material.
See the attached example


Material_Nodes.blend (114 KB)

Thank you all!