Property/cs

Introduction

Boolean
Float
FloatList
FloatConstraint
Angle
Distance
Integer
IntegerConstraint
Percent
Enumeration
IntegerList
String
StringList
Link
LinkList
Matrix
Vector
VectorList
Placement
PlacementLink
Color
ColorList
Material
Path
File
FileIncluded
PartShape
FilletContour
Circle

Properties play a very important role in FreeCAD. As objects in FreeCAD are "parametric", this means that their behavior is defined by their properties, and how these properties are used as input for their class methods. See also FeaturePython Custom Properties and PropertyLink: InList and OutList

All property types

Custom scripted objects can use any of the property types defined in the base system:

Internally, the property name is prefixed with App::Property:

App::PropertyBool
App::PropertyFloat
App::PropertyFloatList
...

Remember that these are property types. A single object may have many properties of the same type, but with different names.

For example:

obj.addProperty("App::PropertyFloat", "Length")
obj.addProperty("App::PropertyFloat", "Width")
obj.addProperty("App::PropertyFloat", "Height")

This indicates an object with three properties of type "Float", named "Length", "Width", and "Height", respectively.

Scripting

See also: FreeCAD scripting basics

A scripted object is created first, and then properties are assigned.

obj = App.ActiveDocument.addObject("Part::Feature", "CustomObject")

obj.addProperty("App::PropertyFloat", "Velocity", "Parameter", "Body speed")
obj.addProperty("App::PropertyBool", "VelocityEnabled", "Parameter", "Enable body speed")

In general, Data properties are assigned by using the object's addProperty() method. On the other hand, View properties are normally provided automatically by the parent object from which the scripted object is derived.

For example:

• Deriving from App::FeaturePython provides only 4 View properties: "Display Mode", "On Top When Selected", "Show In Tree", and "Visibility".
• Deriving from Part::Feature provides 17 View properties: the previous four, plus "Angular Deflection", "Bounding Box", "Deviation", "Draw Style", "Lighting", "Line Color", "Line Width", "Point Color", "Point Size", "Selectable", "Selection Style", "Shape Color", and "Transparency".

Nevertheless, View properties can also be assigned using the view provider object's addProperty() method.

obj.ViewObject.addProperty("App::PropertyBool", "SuperVisibility", "Base", "Make the object glow")

Source code

In the source code, properties are located in various src/App/Property* files.

They are imported and initialized in src/App/Application.cpp.

#include "Property.h"
#include "PropertyContainer.h"
#include "PropertyUnits.h"
#include "PropertyFile.h"
#include "PropertyLinks.h"
#include "PropertyPythonObject.h"
#include "PropertyExpressionEngine.h"

Power user documentation

• FreeCAD scripting: Python, Introduction to Python, Python scripting tutorial, FreeCAD Scripting Basics

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• Modules: Builtin modules, Units, Quantity
• Workbenches: Workbench creation, Gui Commands, Commands, Installing more workbenches
• Meshes and Parts: Mesh Scripting, Topological data scripting, Mesh to Part, PythonOCC

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• Parametric objects: Scripted objects, Viewproviders (Custom icon in tree view)
• Scenegraph: Coin (Inventor) scenegraph, Pivy
• Graphical interface: Interface creation, Interface creation completely in Python (1, 2, 3, 4, 5), PySide, PySide examples beginner, intermediate, advanced
• Macros: Macros, How to install macros
• Embedding: Embedding FreeCAD, Embedding FreeCADGui

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• Other: Expressions, Code snippets, Line drawing function, FreeCAD vector math library (deprecated)

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• Hubs: User hub, Power users hub, Developer hub