How can I change an object only when other object is selected?

[pdaraujo]

I'm browsing MEL and expressions and trying to do something like this: if I select one object I deactivate one property from another. But I'm having problems with the object selection denomination. The following is an example:

If (select pCube1-r on) {
PCube2.visibility = 0;
}
I have tried with strings too but it didn't work...

global proc myscript() {
string $a[] = ls -sl;
if ($a[0] == "pCube1")
hide = "pCube2";
else;
}
scriptJob -e"SelectionChanged" "myScript";

Can someone help?

Thank you very much!

[pdaraujo]

I have tried this way and worked it!!

string $sel[] = ls -sl;
string $item;
for ($item in $sel)
{
if ($item == "pCube1")
{
pCube2.translateX = 15;
}
if ($item == "pCube3")
{
pCube2.translateX = 25;
}
}

But I still have a problem ... it just work once... and I need it works everytime that the selection is changed...

[mehdi-louala]

Hi pdaraujo,
Sorry for late answer,
Did you try to just put your working code into a proc, then you can call a scriptJob which will be triggered everytime the selection changes like you did above ;
global proc myscript() {
string $sel[] = ls -sl;
string $item;
for ($item in $sel)
{
if ($item == "pCube1") {
pCube2.translateX = 15;
} if ($item == "pCube3") {
pCube2.translateX = 25;
}
}
}
scriptJob -e"SelectionChanged" "myScript";

Hope it help

[pdaraujo]

Hi Mehdi-louala, don't worry, thank you for the answer!!!! Im sorry too I just read your answer now...

Thank you so much !!

I have tried this way before but didnt work... When i try without the proc, it works once... I don't know expressions very well so maybe I typed something wrong...
I have doubt when we say that The selection was changed att the end of the expression. In The " " I have to type just SelectionChanged ??

Thank you so much!!

[mehdi-louala]

Ok right I didn't read in details the function you wrote, here is a working one ;
global proc myscript() {
string $sel[] = "ls -sl";
if ($sel[0] == "pCube1") {
setAttr("pCube2.translateX", 15);
} else if ($sel[0] == "pCube3") {
setAttr("pCube2.translateX", 25);
}
}
scriptJob -e "SelectionChanged" "myscript";

Well... There is an issue due to the text editor of the website so you can find the working code here , this text editor just doesn't allow to put a diacritical grave accent which is problematic for MEL code !

And yes this is the common way to declare what is named a callback - which means something triggered everytime the event occurs, in our case a selection change - to write a line like the one at the end of the expression !

By the way you can have a look on this tutorial if you want an introduction to scripting (in Python) in Maya : https://3dbunk.com/introduction_to_python_script
Python is a (little) bit slower than MEL but you can do more advanced tools, scripts and more easy to read

Hope it helps,
Peace,
Mehdi

[pdaraujo]

Thank you!! I will try this way and tell You !!
Thank you very much the tips and links , I will try it too...

[pdaraujo]

Hi Mehdi-louala, how are you? I have tried your links, the first didnt work, but the second is very good!! I liked very much your site!! Thanks to share!!
Do you have facebook profile??

I tried calling proc how you've said, and worked it , Thanks!!! But it just works in the script editor. By the expression editor , it just works without proc ...
Now I have this situation:
On Script Editor it works without and with the callback, but on the expression editor just work without the callback, and because this it just works once...
Thank you!!!