Tag Archives: ExternalEvent

[Revit] Batch view renaming, regular expression, docstrings, a GUI

This batch renaming utility elaboration has been a long journey. I did a simple one long time ago which was supporting only 1 renaming pattern : http://pythoncvc.net/?p=27

Principle

We use parameters available in our views to rename them in a programmatic and logic way. My old script was using an home parameter for discipline and sub-discipline which is set by view template, level and scope box name to make it unique as much as possible.

Objectives

Flexibility : clients, contractors or someone else may ask a specific naming pattern for views. So pattern need to be easily adaptable and savable.

Multilingual : as always, to avoid language dependent behaviour, when it is possible built in parameter name or shared parameter Guid shall be used to retrieve values.

Human readable : parameters storage type may be text, number, id etc… and have a better human readable AsValueString (it is the case for scope boxe).

Free separators choice : we should be able to freely choose and change separator, prefix, suffix between parameters

Flexible selection of view to rename : be able to rename X views then select Y other views and rename it and so on.

Code behind in short

Renaming part

I was thinking about common file re-namers like Ant Renamer. User is able to type parameters as a simple string and add anything he wants between them. The string looks like the old string formatting style with %s %d etc…

So my first attempt was to use python string format like "string{Guid.<Guid>}_{bip.<BuiltInParameterName>_{<parameter_name>}".format(parameter_by_Guid.value, parameter_by_builtinparameter.value, parameter_by_name.value). That was working but somehow it felt weird and slow.

I finally used regular expressions which are very much used for this kind of task in a very efficient way (spelling correction, retrieve a phone number, verify that an email entered by a user looks like one etc…).

So we needed a regular expression to retrieve parameters by Guid :

# Create a regular expression to retrieve Guid (including constructor) in a string
parameterGuidRegex = re.compile(r'''
Guid\( # Guid constructor. Example : Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4")
[\" | \'] # Single or double quote required in Guid constructor
([0-9a-f]{8} # First 8 hexa
(-?[0-9a-f]{4}){3} # Optional separator + 4 hexa 3 times
-?[0-9a-f]{12}) # Optional separator + 12 hexa
[\" | \'] # Single or double quote required in Guid constructor
\) # Close parenthesis necessary to build a Guid
''', re.IGNORECASE | re.VERBOSE)

… by BuiltInParameter (way far simpler) :

# Create a regular expression to retrieve BuiltInParameter in a string
parameterBipRegex = re.compile(r"bip\((\w+)\)")

… and finally by name :

# Create a regular expression to retrieve named parameters in a string
parameterNameRegex = re.compile(r"name\(([\w\s]+)\)") # Retrieve group(1)

There is mainly 3 class of view (excluding schedules, legends etc…) : ViewPlan, View3D, ViewSection. Each kind don’t have the same available parameter. For example there is no level parameter  in 3D and section views. So 3 pattern definition was required to batch rename views. To show available parameters to user a sample view of each class is retrieved and parameters Guid, BuiltInParameterName, and Name are stored as a dictionary.

To help user add parameter to pattern the best way. A function try to retrieve Guid else BuiltInParameter name else name.

Another function replace pattern by their associated parameter name and value to show user a preview.

A last function is in charge of actually renaming views.

GUI part

A WPF GUI splitted in 4 part, 3 for each view classes, 1 for saving and validation options.

Saving/loading part

Thanks again to Ehsan, there is a very easy way to save script parameter to pyRevit config file. Don’t forget to encode and decode your string !

my_config = this_script.config
# Then in WPF class we have following method :

def save_config_click(self, sender, e):
 for view_class in self.view_class_dict.keys():
 view_class_checkbox = eval('self.cb_{}'.format(view_class))
 if view_class_checkbox.IsChecked:
 pattern_textbox = eval('self.{}_pattern'.format(view_class))
 setattr(my_config, view_class, pattern_textbox.Text.encode('utf8'))
 this_script.save_config()

But I wanted also to be able to save to a parameter for project specific naming rules. Unfortunately with Revit API it is still currently not possible to create a project parameter which is not shared. So based on Spiderinnet samples I wrote a function to create a shared parameter and store configuration in it as a string which is formatted in a dictionary/json style.

When script is launched. It tries to load configuration from project parameter (as project specific case should be use first) else from pyRevit config file (the way you name it on your office) else from default values (which are for most people just samples).

Modeless / ExternalEvent part

To be able to rename successively multiple selections of views it was mandatory to use a modelless WPF window and so to use ExternalEvent for any Transaction to Revit : create shared parameter, save to parameter, rename views. I described how to do so in a previous article but as there was 3 different action to make it was a good idea to enhance it. I made 2 class to be able to execute any function or method through the external event using *args and *kwargs :

class CustomizableEvent:
 def __init__(self):
 self.function_or_method = None
 self.args = ()
 self.kwargs = {}

 def raised_method(self):
 self.function_or_method(*self.args, **self.kwargs)

 def raise_event(self, function_or_method, *args, **kwargs):
 self.args = args
 self.kwargs = kwargs
 self.function_or_method = function_or_method
 custom_event.Raise()


customizable_event = CustomizableEvent()


# Create a subclass of IExternalEventHandler
class CustomHandler(IExternalEventHandler):
 """Input : function or method. Execute input in a IExternalEventHandler"""

 # Execute method run in Revit API environment.
 # noinspection PyPep8Naming, PyUnusedLocal
 def Execute(self, application):
 try:
 customizable_event.raised_method()
 except InvalidOperationException:
 # If you don't catch this exeption Revit may crash.
 print "InvalidOperationException catched"

 # noinspection PyMethodMayBeStatic, PyPep8Naming
 def GetName(self):
 return "Execute an function or method in a IExternalHandler"


# Create an handler instance and his associated ExternalEvent
custom_handler = CustomHandler()
custom_event = ExternalEvent.Create(custom_handler)

Full source code

As usual full source code is available on github.

Video demo

To learn more about

Thanks to all these resources which helped a lot

WPF tutorial :

http://www.wpf-tutorial.com/

string format :

https://pyformat.info/

Regular expressions :

https://www.udemy.com/automate/learn/v4/overview

https://automatetheboringstuff.com/chapter7/

https://docs.python.org/3.6/library/re.html

Encoding :

http://sametmax.com/lencoding-en-python-une-bonne-fois-pour-toute/

Docstring :

http://sametmax.com/lencoding-en-python-une-bonne-fois-pour-toute/

https://www.python.org/dev/peps/pep-0257/

*args and **kwargs :

http://deusyss.developpez.com/tutoriels/Python/args_kwargs/

[Revit] Rotate elements in any direction script

More than 2 years ago I made an article to show a way to rotate element using Revit API. Using external events in a modeless form as described in my previous article you can for example make a GUI to get axis and angle from user inputs. It is also using ISelectionFilter as described in this previous article. The new thing is that I use a standard class to store rotation parameters. This way parameters are dynamically feed to methods which are run in external events.

Let’s see this in action :

Full source code with comments (designed to be used in pyRevit) :

from revitutils import doc, uidoc
from scriptutils.userinput import WPFWindow

# noinspection PyUnresolvedReferences
from Autodesk.Revit.DB import Transaction, ElementTransformUtils, Line, XYZ, Location, UnitType, UnitUtils
# noinspection PyUnresolvedReferences
from Autodesk.Revit.UI.Selection import ObjectType, ISelectionFilter
# noinspection PyUnresolvedReferences
from Autodesk.Revit.UI import IExternalEventHandler, IExternalApplication, Result, ExternalEvent, IExternalCommand
# noinspection PyUnresolvedReferences
from Autodesk.Revit.Exceptions import InvalidOperationException, OperationCanceledException


__doc__ = "Rotate object in any direction"
__title__ = "3D Rotate"
__author__ = "Cyril Waechter"

# Get current project units for angles
angle_unit = doc.GetUnits().GetFormatOptions(UnitType.UT_Angle).DisplayUnits


def xyz_axis(element_id):
    """Input : Element, Output : xyz axis of the element"""
    origin = doc.GetElement(element_id).Location.Point
    xyz_direction = [XYZ(origin.X + 1, origin.Y, origin.Z),
                     XYZ(origin.X, origin.Y + 1, origin.Z),
                     XYZ(origin.X, origin.Y, origin.Z + 1)]
    axis = []
    for direction in xyz_direction:
        axis.append(Line.CreateBound(origin, direction))
    return axis


class AxisISelectionFilter(ISelectionFilter):
    """ISelectionFilter that allow only which have an axis (Line)"""

    # noinspection PyMethodMayBeStatic, PyPep8Naming
    def AllowElement(self, element):
        if isinstance(element.Location.Curve, Line):
            return True
        else:
            return False


def axis_selection():
    """Ask user to select an element, return the axis of the element"""
    try:
        reference = uidoc.Selection.PickObject(ObjectType.Element, AxisISelectionFilter(), "Select an axis")
    except OperationCanceledException:
        pass
    else:
        axis = doc.GetElement(reference).Location.Curve
        return axis


class RotateElement(object):
    """class used to store rotation parameters. Methods then rotate elements."""
    def __init__(self):
        self.selection = uidoc.Selection.GetElementIds()
        self.angles = [0]

    def around_itself(self):
        """Method used to rotate elements on themselves"""
        try:
            t = Transaction(doc, "Rotate around itself")
            t.Start()
            for elid in self.selection:
                el_axis = xyz_axis(elid)
                for i in range(3):
                    if self.angles[i] == 0:
                        pass
                    else:
                        ElementTransformUtils.RotateElement(doc, elid, el_axis[i], self.angles[i])
            t.Commit()
        except InvalidOperationException:
            import traceback
            traceback.print_exc()
        except:
            import traceback
            traceback.print_exc()

    def around_axis(self):
        """Method used to rotate elements around selected axis"""
        try:
            axis = axis_selection()
            t = Transaction(doc, "Rotate around axis")
            t.Start()
            ElementTransformUtils.RotateElements(doc, self.selection, axis, self.angles)
            t.Commit()
        except InvalidOperationException:
            import traceback
            traceback.print_exc()
        except:
            import traceback
            traceback.print_exc()
        finally:
            uidoc.Selection.SetElementIds(rotate_elements.selection)

rotate_elements = RotateElement()


# Create a subclass of IExternalEventHandler
class RotateElementHandler(IExternalEventHandler):
    """Input : function or method. Execute input in a IExternalEventHandler"""

    # __init__ is used to make function from outside of the class to be executed by the handler. \
    # Instructions could be simply written under Execute method only
    def __init__(self, do_this):
        self.do_this = do_this

    # Execute method run in Revit API environment.
    # noinspection PyPep8Naming, PyUnusedLocal
    def Execute(self, application):
        try:
            self.do_this()
        except InvalidOperationException:
            # If you don't catch this exeption Revit may crash.
            print "InvalidOperationException catched"

    # noinspection PyMethodMayBeStatic, PyPep8Naming
    def GetName(self):
        return "Execute an function or method in a IExternalHandler"

# Create handler instances. Same class (2 instance) is used to call 2 different method.
around_itself_handler = RotateElementHandler(rotate_elements.around_itself)
around_axis_handler = RotateElementHandler(rotate_elements.around_axis)
# Create ExternalEvent instance which pass these handlers
around_itself_event = ExternalEvent.Create(around_itself_handler)
around_axis_event = ExternalEvent.Create(around_axis_handler)


class RotateOptions(WPFWindow):
    """
    Modeless WPF form used for rotation angle input
    """

    def __init__(self, xaml_file_name):
        WPFWindow.__init__(self, xaml_file_name)
        self.set_image_source("xyz_img", "XYZ.png")
        self.set_image_source("plusminus_img", "PlusMinusRotation.png")

    # noinspection PyUnusedLocal
    def around_itself_click(self, sender, e):
        try:
            rotate_elements.selection = uidoc.Selection.GetElementIds()
            angles = [self.x_axis.Text, self.y_axis.Text, self.z_axis.Text]
            for i in range(3):
                angles[i] = UnitUtils.ConvertToInternalUnits(float(angles[i]), angle_unit)
            rotate_elements.angles = angles
        except ValueError:
            self.warning.Text = "Incorrect angles, input format required '0.0'"
        else:
            self.warning.Text = ""
            around_itself_event.Raise()

    # noinspection PyUnusedLocal
    def around_axis_click(self, sender, e):
        try:
            rotate_elements.angles = UnitUtils.ConvertToInternalUnits(float(self.rotation_angle.Text), angle_unit)
            rotate_elements.selection = uidoc.Selection.GetElementIds()
        except ValueError:
            self.warning.Text = "Incorrect angles, input format required '0.0'"
        else:
            around_axis_event.Raise()

RotateOptions('RotateOptions.xaml').Show()

Enjoy !

[Revit API] Simple Modeless Form (External Event Handler) in pyRevit

I struggled for a while to make a modeless form. Why did I need it ? Because each time I was trying to get user to select object after WPF appear I was going out of Revit API thread and got this very common exception «Autodesk.Revit.Exceptions.InvalidOperationException: Attempting to create an ExternalEvent outside of a standard API execution». As Jeremy Tammik says :

One of the most frequently raised questions around the Revit API is how to drive Revit from outside, e.g., from a separate thread, a modeless dialogue, or a stand-alone executable.

I have read many examples on the subject. Most on them were in C#.

So I made a very simple form to make a very simple ExternalEventHandler sample as pyRevit script. It will help me and I hope it will help some hackers to struggle less than I did.

Let’s start with common import statement using built-in pyRevit utils :

# noinspection PyUnresolvedReferences
from Autodesk.Revit.UI import IExternalEventHandler, ExternalEvent
# noinspection PyUnresolvedReferences
from Autodesk.Revit.DB import Transaction
# noinspection PyUnresolvedReferences
from Autodesk.Revit.Exceptions import InvalidOperationException
from revitutils import selection, uidoc, doc
from scriptutils.userinput import WPFWindow

__doc__ = "A simple modeless form sample"
__title__ = "Modeless Form"
__author__ = "Cyril Waechter"

Then let’s write a simple function we want to execute modeless  (here it just delete selected elements) :

# Simple function we want to run
def delete_elements():
    t = Transaction(doc, "Failing script")
    t.Start()
    for elid in uidoc.Selection.GetElementIds():
        print elid
        doc.Delete(elid)
    t.Commit()

And now come the new magic thing that let you enter in a valid Revit API context. The «ExternalEvent» class with his «IExternalEventHandler» class :

# Create a subclass of IExternalEventHandler
class SimpleEventHandler(IExternalEventHandler):
    """
    Simple IExternalEventHandler sample
    """

    # __init__ is used to make function from outside of the class to be executed by the handler. \
    # Instructions could be simply written under Execute method only
    def __init__(self, do_this):
        self.do_this = do_this

    # Execute method run in Revit API environment.
    def Execute(self, uiapp):
        try:
            self.do_this()
        except InvalidOperationException:
            # If you don't catch this exeption Revit may crash.
            print "InvalidOperationException catched"

    def GetName(self):
        return "simple function executed by an IExternalEventHandler in a Form"


# Now we need to make an instance of this handler. Moreover, it shows that the same class could be used to for
# different functions using different handler class instances
simple_event_handler = SimpleEventHandler(delete_elements)
# We now need to create the ExternalEvent
ext_event = ExternalEvent.Create(simple_event_handler)

Let’s do a simple form so easily created thanks to pyRevit in order to use our new toy :

# A simple WPF form used to call the ExternalEvent
class ModelessForm(WPFWindow):
    """
    Simple modeless form sample
    """

    def __init__(self, xaml_file_name):
        WPFWindow.__init__(self, xaml_file_name)
        self.simple_text.Text = "Hello World"
        self.Show()

    def delete_click(self, sender, e):
        # This Raise() method launch a signal to Revit to tell him you want to do something in the API context
        ext_event.Raise()

# Let's launch our beautiful and useful form !
modeless_form = ModelessForm("ModelessForm.xaml")

Here is the xaml code :

<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 Title="Delete things:" Height="150" Width="300" ShowInTaskbar="False" Topmost="True"
 WindowStartupLocation="CenterScreen" ScrollViewer.VerticalScrollBarVisibility="Disabled" HorizontalContentAlignment="Center">
 <StackPanel Margin="20" HorizontalAlignment="Stretch">
 <TextBlock x:Name="simple_text" Text="" Grid.Column="0" HorizontalAlignment="Center" FontWeight="Bold"/>
 <Button Content="Delete selected elements" Height="30" Margin="10,10" Click="delete_click"/>
 </StackPanel>
</Window>

Thanks a lot to all people mentioned in this article and linked article and stuffs.