Develop Reference

How to change username of job in print queue using python & win32print

I am trying to change the user of a print job in the queue, as I want to create it on a service account but send the job to another users follow-me printing queue. I'm using the win32 module in python. Here is an example of my code:
from win32 import win32print
JOB_INFO_LEVEL = 2
pclExample = open("sample.pcl")
printer_name = win32print.GetDefaultPrinter()
hPrinter = win32print.OpenPrinter(printer_name)
try:
jobID = win32print.StartDocPrinter(hPrinter, 1, ("PCL Data test", None, "RAW"))
# Here we try to change the user by extracting the job and then setting it again
jobInfoDict = win32print.GetJob(hPrinter, jobID , JOB_INFO_LEVEL )
jobInfoDict["pUserName"] = "exampleUser"
win32print.SetJob(hPrinter, jobID , JOB_INFO_LEVEL , jobInfoDict , win32print.JOB_CONTROL_RESUME )
try:
win32print.StartPagePrinter(hPrinter)
win32print.WritePrinter(hPrinter, pclExample)
win32print.EndPagePrinter(hPrinter)
finally:
win32print.EndDocPrinter(hPrinter)
finally:
win32print.ClosePrinter(hPrinter)
The problem is I get an error at the win32print.SetJob() line. If JOB_INFO_LEVEL is set to 1, then I get the following error:
(1804, 'SetJob', 'The specified datatype is invalid.')
This is a known bug to do with how the C++ works in the background (Issue here).
If JOB_INFO_LEVEL is set to 2, then I get the following error:
(1798, 'SetJob', 'The print processor is unknown.')
However, this is the processor that came from win32print.GetJob(). Without trying to change the user this prints fine, so I'm not sure what is wrong.
Any help would be hugely appreciated! :)
EDIT:
Using Python 3.8.5 and Pywin32 303

At the beginning I thought it was a misunderstanding (I was also a bit skeptical about the bug report), mainly because of the following paragraph (which apparently seems to be wrong) from [MS.Docs]: SetJob function (emphasis is mine):
The following members of a JOB_INFO_1, JOB_INFO_2, or JOB_INFO_4 structure are ignored on a call to SetJob: JobId, pPrinterName, pMachineName, pUserName, pDrivername, Size, Submitted, Time, and TotalPages.
But I did some tests and ran into the problem. The problem is as described in the bug: filling JOB_INFO_* string members (which are LPTSTRs) with char* data.
Submitted [GitHub]: mhammond/pywin32 - Fix: win32print.SetJob sending ANSI to UNICODE API (and none of the 2 errors pops up). It was merged to main on 220331.
When testing the fix, I was able to change various properties of an existing job, I was amazed that it didn't have to be valid data (like below), I'm a bit curious to see what would happen when the job would be executed (as now I don't have a connection to a printer):
Change pUserName to str(random.randint(0, 10000)) to make sure it changes on each script run (PrintScreens taken separately and assembled in Paint):
Ways to go further:
Wait for a new PyWin32 version (containing this fix) to be released. This is the recommended approach, but it will also take more time (and it's unclear when it will happen)
Get the sources, either:
from main
from b303 (last stable branch), and apply the (above) patch(1)
build the module (.pyd) and copy it in the PyWin32's site-packages directory on your Python installation(s). Faster, but it requires some deeper knowledge, and maintenance might become a nightmare
Footnotes
#1: Check [SO]: Run / Debug a Django application's UnitTests from the mouse right click context menu in PyCharm Community Edition? (#CristiFati's answer) (Patching UTRunner section) for how to apply patches (on Win).

Getting a selection in 3ds Max into a list in Python

I am writing in Python, sometimes calling certain aspects of maxscript and I have gotten most of the basics to work. However, I still don't understand FPValues. I don't even understand while looking through the examples and the max help site how to get anything meaningful out of them. For example:
import MaxPlus as MP
import pymxs
MPEval = MP.Core.EvalMAXScript
objectList = []
def addBtnCheck():
select = MPEval('''GetCurrentSelection()''')
objectList.append(select)
print(objectList)
MPEval('''
try (destroyDialog unnamedRollout) catch()
rollout unnamedRollout "Centered" width:262 height:350
(
button 'addBtn' "Add Selection to List" pos:[16,24] width:88 height:38
align:#left
on 'addBtn' pressed do
(
python.Execute "addBtnCheck()"
)
)
''')
MP.Core.EvalMAXScript('''createDialog unnamedRollout''')
(I hope I got the indentation right, pretty new at this)
In the above code I successfully spawned my rollout, and used a button press to call a python function and then I try to put the selection of a group of objects in a variable that I can control through python.
The objectList print gives me this:
[<MaxPlus.FPValue; proxy of <Swig Object of type 'Autodesk::Max::FPValue *' at 0x00000000846E5F00> >]
When used on a selection of two objects. While I would like the object names, their positions, etc!
If anybody can point me in the right direction, or explain FPValues and how to use them like I am an actual five year old, I would be eternally grateful!

Where to start, to me the main issue seems to be the way you're approaching it:
why use MaxPlus at all, that's an low-level SDK wrapper as unpythonic (and incomplete) as it gets
why call maxscript from python for things that can be done in python (getCurrentSelection)
why use maxscript to create UI, you're in python, use pySide
if you can do it in maxscript, why would you do it in python in the first place? Aside from faster math ops, most of the scene operations will be orders of magnitude slower in python. And if you want, you can import and use python modules in maxscript, too.

import MaxPlus as MP
import pymxs
mySel = mp.SelectionManager.Nodes
objectList = []
for each in mySel:
x = each.Name
objectList.append(x)
print objectList

The easiest way I know is with the
my_selection = rt.selection
command...
However, I've found it works a little better for me to throw it into a list() function as well so I can get it as a Python list instead of a MAXscript array. This isn't required but some things get weird when using the default return from rt.selection.
my_selection = list(rt.selection)
Once you have the objects in a list you can just access its attributes by looking up what its called for MAXscript.
for obj in my_selection:
print(obj.name)

can't add columns in wxPython virtual grid

I have a wxPython GUI with a very large grid. I am using similar code to the GridHugeTable.py example from the wxPython demo -- i.e., using PyGridTableBase to make a virtual grid.
I am running into trouble when I try to interactively add columns to this grid, however.
Calling AppendCols(1) results in this error:
wx._core.PyAssertionError: C++ assertion "Assert failure" failed at /Users/vagrant/pisi-64bit/tmp/wxPython-3.0.2.0-3/work/wxPython-src-3.0.2.0/src/generic/grid.cpp(1129) in AppendCols():
Called grid table class function AppendCols but your derived table class does not override this function
But if I try to overwrite AppendCols in my table class, the application just hangs indefinitely and never resolves. It hangs even if there is actually nothing in my custom AppendCols method at all...
class HugeTable(gridlib.PyGridTableBase):
"""
Table class for virtual grid
"""
def __init__(self, log, num_rows, num_cols):
gridlib.PyGridTableBase.__init__(self)
def AppendCols(self, *args):
pass
I've been able to overwrite other methods successfully, (setValue, getValue, getColLabelValue, etc.), so I'm not sure what is different here.
Update:
I returned to this problem after a while away. I no longer get the wx.__core.PyAssertionError. However, I still can't get my custom AppendCols method to work. I can't figure out what to put in AppendCols to make a new column actually show up.
I'm not sure how to look in the source code -- none of the Python documentation seems to have what I'm looking for, so maybe I need to go digging in wxWidgets? The documentation hasn't helped: https://wiki.wxpython.org/wxPyGridTableBase.

The clue I needed is in the the demo code for custom table.
So, this code works (leaving out my custom logic and just including the bare bones):
def AppendCols(self, *args):
msg = gridlib.GridTableMessage(self, # The table
gridlib.GRIDTABLE_NOTIFY_COLS_APPENDED, # what we did to it
1) # how many
self.GetView().ProcessTableMessage(msg)
return True

Heavily confused by win32api + COM and an answer from SO

From my other question here on SO, I asked how to retrieve the current playing song from Windows Media Player and Zune, I got an answer from a c++ dev who gave me an explanation of how I would do this for WMP.
However, I am no C++ dev, nor am I very experienced with the pywin32 library. And on-top of all that, the documentation on all this (especially concerning WMP) is horrible.
Therefor, I need your help understanding how I would do the following in Python.
Source
I have working code in C++ to print the name of media currently
playing in WMP. It's a simple console application (78 lines of code).
Steps:
1) implements a basic COM object implementing IUnknown, IOleClientSite, IServiceProvider and IWMPRemoteMediaServices. This is
straightforward (sort of, your mileage may vary) using the ATL
template CComObjectRootEx. The only methods needing (simple) code are
IServiceProvider::QueryService and
IWMPRemoteMediaServices::GetServiceType. All other methods may return
E_NOTIMPL
2) Instantiate the "WMPlayer.OCX" COM object (in my case, via CoCreateInstance)
3) Retrieve from the object an IOleObject interface pointer via QueryInterface
4) Instanciate an object from the class seen in 1) (I use the CComObject<>::CreateInstance template)
5) Use the SetClientSite method from the interface you got at 3), passing a pointer to your OleClientSite implementation.
6) During the SetClientSite call, WMP will callback you: fisrt asking for an IServiceProvider interface pointer, second calling the
QueryService method, asking for an IWMPRemoteMediaServices interface
pointer. Return your implementation of IWMPRemoteMediaServices and,
third, you will be called again via GetServiceType. You must then
return "Remote". You are now connected to the WMP running instance
7) Query the COM object for an IWMPMedia interface pointer
8) If 7) didn't gave NULL, read the the IWMPMedia::name property.
9) DONE
All the above was tested with VS2010 / Windows Seven, and with WMP
running (if there is no Media Player process running, just do
nothing).
I don't know if yoy can/want to implement COM interface and object in
Python. If you are interested by my C++ code, let me know. You could
use that code in a C++ DLL, and then call it from python.
I know a little bit about the win32api.
At the first step, I really don't know what to do, googling IOleClientSite results in the msdn documentation, it's an interface. However, that's where I get stuck already. I can't find anything (might just be my horrendous googling skills) on working with these things in Python.
The second step:
WMP = win32com.client.Dispatch("WMPlayer.OCX")
Alright, that's doable.
On to the third step. QueryInterface -
"regardless of the object you have, you can always call its QueryInterface() method to obtain a new interface, such as IStream."
source
However, not for me. As I understand his explanation, I think it means that every com object sort of "inherits" three methods from IUnknown, one of which is QueryInterface, however this does not seem the case since calling QueryInterface on my WMP object fails miserably. (Object has no attribute 'QueryInterface')
I could ramble on, but I believe you got the point, I have no idea how to work with this. Can anyone help me out with this one? Preferably with code examples, but resources/documentation is welcome too.

Almost final answser but CAN'T finish.
I seems that pythoncom can't be used to implement custom Interface without the help of a C++ module.
Here is an answser from Mark Hammon (Mon, 13 Jan 2003): How to create COM Servers with IID_IDTExtensibility2 interface
Sorry - you are SOL. To support arbitary interfaces, you need C++
support, in the form of an extension module. There is a new "Univgw"
that may help you out, but I dont know much about this
I am not able to find anything about that "Univgw" thing...
The comtypes python module is intended to resolve the problem, and I found links saying it does, but I can't make it works with my fresh new Python 3.3. It's Python 2.x code. comtypes seems outdated and unmaintained.
Step 1 OK for IOleClientSite and IServiceProvider, KO for IWMPRemoteMediaServices
Step 2, 3, 4 and 5 OK
Step 6, 7 and 8 can't be implemented without IWMPRemoteMediaServices :-(
disclaimer: complete newbie in Python, please don't yell
import pythoncom
import win32com.client as wc
from win32com.axcontrol import axcontrol
import win32com.server as ws
from win32com.server import util
from win32com.server.exception import COMException
import winerror
import pywintypes
# Windows Media Player Custom Interface IWMPRemoteMediaServices
IWMPRemoteMediaServices = pywintypes.IID("{CBB92747-741F-44FE-AB5B-F1A48F3B2A59}")
class OleClientSite:
_public_methods_ = [ 'SaveObject', 'GetMoniker', 'GetContainer', 'ShowObject', 'OnShowWindow', 'RequestNewObjectLayout', 'QueryService' ]
_com_interfaces_ = [ axcontrol.IID_IOleClientSite, pythoncom.IID_IServiceProvider ]
def SaveObject(self):
print("SaveObject")
raise COMException(hresult=winerror.E_NOTIMPL)
def GetMoniker(self, dwAssign, dwWhichMoniker):
print("GetMoniker ")
raise COMException(hresult=winerror.E_NOTIMPL)
def GetContainer(self):
print("GetContainer")
raise COMException(hresult=winerror.E_NOTIMPL)
def ShowObject(self):
print("ShowObject")
raise COMException(hresult=winerror.E_NOTIMPL)
def OnShowWindow(self, fShow):
print("ShowObject" + str(fShow))
raise COMException(hresult=winerror.E_NOTIMPL)
def RequestNewObjectLayout(self):
print("RequestNewObjectLayout")
raise COMException(hresult=winerror.E_NOTIMPL)
def QueryService(self, guidService, riid):
print("QueryService",guidService,riid)
if riid == IWMPRemoteMediaServices:
print("Known Requested IID, but can't implement!")
raise COMException(hresult=winerror.E_NOINTERFACE)
else:
print("Requested IID is not IWMPRemoteMediaServices" )
raise COMException(hresult=winerror.E_NOINTERFACE)
if __name__=='__main__':
wmp = wc.Dispatch("WMPlayer.OCX")
IOO = wmp._oleobj_.QueryInterface(axcontrol.IID_IOleObject)
pyOCS = OleClientSite()
comOCS = ws.util.wrap(pyOCS, axcontrol.IID_IOleClientSite)
IOO.SetClientSite(comOCS)

Assign string to QLineEdit with PySide/PyQt

I'm having a little bit of trouble assigning values to a QLineEdit. I've read the documentation and feel that the QLineEdit.SetText() command will be used at some point.
I've used Qt Designer to design a GUI for my software. On the main window (MainWindow.py, with an accompanying ui_MainWindow.py setup file), I have a LineEdit (lineEditScanBarcode) which has strong focus. I've managed to pull input from that LineEdit pretty well. What I'd like to do is this:
If the input in LineEditScanBarcode = x, then assign the name 'John Smith' to a secondary QLineEdit (lineEditUser) which has a zero focus policy. This is what I have so far:
def ScanBarcode(self):
barcode = self.lineEditScanBarcode.text()
self.lineEditScanBarcode.clear()
if barcode == '12345':
print("Welcome John")
self.lineEditUser.setText() = 'John'
else: print("Sorry, user not recognised.")
Upon running this, I get the following error:
Syntax Error: can't assign to function call
I've had a look at the above error, but I'm still unsure as to what's going on here. I still have no idea to open one window on top of another (this software package will have about 10 windows), but that's another story!
Is my logic here on track? I've never used Qt before, so my understanding of the intricacies involved is lacking to say the least.
Any input would be great!

As the comment states, the error is on this line:
self.lineEditUser.setText() = 'John'
You are attempting to assign the value 'John' to that functioncall (as the error states). If you review the documentation for QLineEdit in PyQT, you'll see that QLineEdit.setText() requires a string to be passed to it.
So, what you need to do instead is pass the value 'John' to the function like so:
self.lineEditUser.setText('John')
On another note your idea that your
software package will have about 10 windows
is definitely something that you want to reexamine. More windows, especially when undocked and floating independently will no doubt cause usability issues. I'd strongly recommend sharing your ideas over at UserExperience.SE.