how add custom properties to any object?

[openBrain]

Can you access custom properties of a parent object?

Like if I have a Sketch, inside of a Body inside of a Part, can I add a custom property to the Part then access that as a dimension constraint in the Sketch? How?

Just set in an expression

Code: Select all

=PARTNAME.PROPERTYNAME

[hmk]

Just set in an expression

Code: Select all

=PARTNAME.PROPERTYNAME

More details here: https://wiki.freecadweb.org/Expressions ... ng_objects

[Zolko]

Can you access custom properties of a parent object? Like if I have a Sketch, inside of a Body inside of a Part, can I add a custom property to the Part then access that as a dimension constraint in the Sketch? How?

No, you can't, that would create a cyclic dependency. Unfortunately, because that would be extremely useful

[ifohancroft]

Can you access custom properties of a parent object? Like if I have a Sketch, inside of a Body inside of a Part, can I add a custom property to the Part then access that as a dimension constraint in the Sketch? How?

No, you can't, that would create a cyclic dependency. Unfortunately, because that would be extremely useful

Thank you!

Also, yeah. It would help a lot if it was possible.

[ifohancroft]

Can you access custom properties of a parent object?

Like if I have a Sketch, inside of a Body inside of a Part, can I add a custom property to the Part then access that as a dimension constraint in the Sketch? How?

Just set in an expression

Code: Select all

=PARTNAME.PROPERTYNAME

Just set in an expression

Code: Select all

=PARTNAME.PROPERTYNAME

More details here: https://wiki.freecadweb.org/Expressions ... ng_objects

Attaching the file for reference, but it doesn't seem to work.

I have a Part called Keyboard, inside it I have a Body called Plate and inside it I have a Sketch that I haven't renamed.
I added a length property to the Keyboard part and called it switch. Trying to access it either as =Keyboard.switch or =<<Keyboard>>.switch I get:
Result: cyclic reference to Unnamed#Part

OS: Manjaro Linux (MATE/mate)
Word size of FreeCAD: 64-bit
Version: 0.20.25288 (Git) AppImage
Build type: Release
Branch: master
Hash: bbb557aab6129efd9486d6df19f06c2976fdb7e5
Python version: 3.9.6
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: English/United States (en_US)

[openBrain]

I have a Part called Keyboard, inside it I have a Body called Plate and inside it I have a Sketch that I haven't renamed.
I added a length property to the Keyboard part and called it switch. Trying to access it either as =Keyboard.switch or =<<Keyboard>>.switch I get:
Result: cyclic reference to Unnamed#Part

Yep, as @zolko explained it creates a cyclic dependency in the expression engine.

[drmacro]

Hmm...it does work, but, doing that creates a cyclic reference because the sub object would be referencing something that is part of what defines the sub-object.

If you create a another Std_Part and add a property called macswitch as shown below, it's fine.

macswitch.png (89.44 KiB) Viewed 2442 times

[ifohancroft]

I have a Part called Keyboard, inside it I have a Body called Plate and inside it I have a Sketch that I haven't renamed.
I added a length property to the Keyboard part and called it switch. Trying to access it either as =Keyboard.switch or =<<Keyboard>>.switch I get:
Result: cyclic reference to Unnamed#Part

Yep, as @zolko explained it creates a cyclic dependency in the expression engine.

Hmm...it does work, but, doing that creates a cyclic reference because the sub object would be referencing something that is part of what defines the sub-object.

If you create a another Std_Part and add a property called macswitch as shown below, it's fine.

macswitch.png

Ah! Got it. Thank you!

[jtm2020hyo]

yes, sounds possible and until I know there exist different methods.

[hmk]

For what it's worth, it seem to work for a special case:

1) Define the custom properties in a Body:

Screenshot from 2021-11-17 17-31-59.png (47.25 KiB) Viewed 1946 times

2) Create a PartDesign shape (e.g., a Cylinder) and in an expression use the shape's _Body property to "reach up" to its parent Body:

Screenshot from 2021-11-17 17-33-36.png (80.14 KiB) Viewed 1946 times

3) Sometimes a wild expression can get you up to the parent Body, for example an expression inside a Sketch

Screenshot from 2021-11-17 17-44-25.png (89.56 KiB) Viewed 1946 times