I'm trying to make a program using PyQt5 and pyqtgraph, however, I keep running into this error:
ImportError: cannot import name 'QGraphWidget'
I used QtDesigner to make a form and promoted a QGraphicsWidget. I know I did it correctly (I've done it at least 10 times to try and resolve the issue), but the error persists.
I'm using Windows 7, Anaconda, and PyCharm, but I tried running the code in other environments and still got the error.
In the documentation it implies that the promoted name can be anything, however, this seems to be untrue (at least at the moment).
Under “Promoted class name”, enter the class name you wish to use (“PlotWidget”, “GraphicsLayoutWidget”, etc).
After re-doing my QGraphicsWidget for the 6th time, I decided to name it one of the example names in the tutorial, which seems to have solved the problem.
In other words name your widget and promoted widget "PlotWidget", "ImageView", "GraphicsLayoutView", or "GraphicsView". (Please keep in mind I have only tested "PlotWidget".)
Related
I'm very new to pyside, qt and python.
I managed to setup a project with a basic window and a push button which closes the app.
My problem is, that somehow vscode won't show all properties available, even though the code runs with them fine.
Note how a bunch of other properties are suggested, except for the signal clicked. If I hover over clicked, it tells me clicked: Any
Only during debugging, vscode tells me what clicked is:
Current setup:
OS: Linux
Virtualenv with pyside2 installed
Using ms-python.python and ms-python.vscode-pylance
ui/MainWindow.ui file and corresponding generated ui/MainWindow_ui.ui file with pyside2-uic
You can generate the stubs manually by running
pyside6-genpyi all
PySide2 have the same tools, it's not just for PySide6.
I use PDM to handle my project, with the last one I execute:
pdm run pyside6-genpyi all
And PyLance detect all my stubs:
If you got error with the Signal, it's because Qt/PySide do some magic tricks and convert Signal to SignalInstance. My solution is to cast SignalInstance to get to right hint.
from typing import cast
from PySide6.QtCore import Signal, SignalInstance
class ConnectionPanel(QtWidgets.QWidget):
connected = cast(SignalInstance, Signal())
disconnected = cast(SignalInstance, Signal())
Pylance tries to use stub files(which you can traverse with Go to definition) of PySide6 library to offer intellisense features. According to Qt docs clicked signal should be defined in QAbstractButton class but in type definitions (stubs) we can't see this signal definitions. If you look closely PyCharm gathers it from QAbstractButton class in your linked video but Pylance in Vs Code searches it in QPushButton.
This was a known issue in Pylance since PySide2 but according to the Pylance repo this may originate from Qt for Python's incorrect type definitions:
Libraries that have typing that's either incorrect or doesn't work well with PyLance. Best and maybe most known example I have is PySide2 (but see issues with other libraries in earlier posts): tons(!) of errors for correct, working code, which makes spotting real errors difficult. The same code in PyQt5 (which is basically a twin sibling to PySide2) doesn't raise any complaints from PyLance, so I'm assuming the problem is with PySide2's typing. While I'm aware that neither PySide2's typing nor PyLance's analysis results are necessarily incorrect, fact is that most of the reported errors should not be present, so for sake of simplicity I'll just call it incorrect.
The reason it can access at runtime is; it's created instance over shiboken QObject type I guess. I don't have any workarounds but it doesn't bother me because I prefer following official Qt documentation when looking for which signals available in a class definition.
EDIT: There was a resolved bug report on this which is the reason PyCharm able to handle auto-completion. Opening another on VS Code should help.
Since I had this exact same problem, I found this very informative comment on a PySide bug report: https://bugreports.qt.io/browse/PYSIDE-1603
Our stubs are auto-generated by introspection, signals are not included. At the moment, we need to discuss how we should support signals.
So, not a bug, just a missing feature.
I am developing a cross platform app in Python using wxPython. The app is fully developed, and the graphics toolkit is set in stone, at least for the time being.
On Windows, everything looks great. On Linux, everything looks pretty good. On Mac, I am having trouble with a combobox/choice being hidden in the toolbar, even though it shows up fine on Windows.
Here is a snapshot of my app on Linux, noting the entire "CoeffConv ..." section is part of the perfectly displayed combobox:
And here is a snapshot of the same exact codebase on Mac:
I've tried with wx.ComboBox and wx.Choice with the same effect. I've made sure to call Realize() after I've added my toolbar items. I've made sure AddControl is called to actually add the object to the toolbar. It's definitely trying to render because the spacing is exactly what I would expect, given the contents of the choice field.
In fact, if I don't call AddControl, but I create the choice field with the toolbar as the parent, the box gets rendered but things aren't arranged properly due to the missing AddControl call:
As another check, I created a super simple toolbar with choice demo, and it works just fine:
So, here's the summary of things I know:
On Windows, the choice field works perfect, indicating the code isn't necessarily wrong.
On Linux, the choice field works perfect, supporting the idea that the code is actually OK.
On Mac, the choice field is present it seems, but somehow invisible, implying this is a problem with the Mac, or the Python distribution on Mac, or the combobox control in the wxPython distribution on Mac.
On Mac, I can get the choice to render (improperly but still) without an AddControl call, indicating the combobox can render properly, but something is goofy about the placement when added to the toolbar
However, On Mac, I can get a toolbar/choice to render totally fine in a dummy example, indicating it's something about my implementation...but I can't figure out what would cause it as I'm trying to make the exact same calls to the wx objects as in the dummy example.
I can't get the dummy example to reproduce the problem, but I'll keep trying. I'm happy to report out some object properties if they would be helpful in diagnosing. If someone has a clue for what could cause it to not show up, I'd really appreciate it!
While I couldn't find the root as to why it didn't work on Mac, I did find an issue that could help others.
First a little more background. In the app, we have multiple toolbars. Because of that, we are creating toolbars using plain wx.ToolBar objects and adding them to the app frame using sizers. This is in contrast to the more standard method of using self.CreateToolBar() which only allows a frame to have a single toolbar.
When I make a single change to the code to use the more natural CreateToolBar interface, the combobox immediately shows up. When I do that, the second toolbar is messed up, but at least the initial toolbar works perfectly. I'll be investigating how to get multiple toolbars on Mac, but it's a step in the right direction.
It's been a while, but there's another solution to this for wxPython 4 if you can't use CreateToolBar():
The widgets do get added to the bar and reserve the correct amount of space, but they fail to draw properly. You can resolve this by calling control.Hide() followed by control.Show() on each widget control, which then makes them draw properly.
Ive got a .ui file made in designer and as soon as i group some radio buttons together, pyside-uic fails to compile the file and return with an unexpected error.
Is there a way around this or am i missing something when adding these groups. Im picking the buttons i need, right clicking and creating a button group from there.
Here is the most basic version of the ui, and this even crashes for me.
http://pastebin.com/0NYHPBUD
after debugging pysideuic, i figured that in module uiparser.py in line 212 the generator fails, because it treats a string like an object.
By changing the source (https://github.com/PySide/Tools/pysideuic/uiparser.py) from:
bg_name = bg_i18n.string
to:
bg_name = bg_i18n
the generator will be working fine.
After further investigation it seems that the implementation of the QButtonGroup changed.
It used to be a Widget.
regards
Ben
I use Python in combination with the gtk3 and the GTKGLExt fork from https://github.com/tdz/gtkglext so I can use the gobject introspection feature to use Gtk3 from python.
I created a Gtk.DrawingArea to draw my OpenGL stuff. Everything works fine as long as I have just one instance of this widget.
However, I use a Gtk Notebook to have multiple instances of this widget present in different pages of the notebook (one widget per page).
Sometimes (meaning in a non deterministic way) the program crashes with a segmentation fault. I ran a stacktrace using gdb and located the problem to be the call to "gtk_widget_end_gl" which is placed at the end of my drawing, realize and configure handler methods (of course there is a gtk_widget_begin_gl at the beginning of each of those as well).
Here is the relevant excerpt from the stacktrace:
0 0xb1170b58 in _gdk_x11_gl_context_impl_get_current () at gdkglcontext-x11.c:514
1 0xb116c094 in gdk_gl_context_get_current () at gdkglcontext.c:244
2 0xb116c0b4 in gdk_gl_context_release_current () at gdkglcontext.c:215
3 0xb4d04592 in gtk_widget_end_gl (widget=0xa175608, do_swap=0) at gtkglwidget.c:549
and below is a minimal example of my realize method where the problem occurs where "widget" is an instance of Gtk.DrawingArea:
def on_realize(self, widget, *user_data):
if not GtkGLExt.widget_begin_gl(widget):
return False
gl.glClearColor(BACKGROUND_COLOR[0],
BACKGROUND_COLOR[1],
BACKGROUND_COLOR[2],
BACKGROUND_COLOR[3])
GtkGLExt.widget_end_gl(widget, False)
Since I am pretty much clueless why this problem occurs sometimes (around every 5th time a new widget is created) I wonder if anyone ever has experienced the same or can reproduce the problem or help me to find a solution.
I need to say that I don't manually create an OpenGL context here since in the provided examples this never seemed necessary and I figured the widget would do this on it's own. The stacktrace implies that there seems to be a problem getting the context. Whats startles me is the fact that this only happens sometimes. So if someone could even hint me how to tackle this problem I would be very glad as I am not an experienced C programmer.
Following the example at http://article.gmane.org/gmane.comp.python.general/541418, I've succeeded in creating a callable class for balloon tooltips, but the greater complexities of that code elude me when it comes to customization. I browsed a bit of how it works through msdn, but being a novice at more windows-esque languagues like c and vb, etc. I was unable to make much sense of it.
So I ask ye snakely academics:
Things I'd like to be able to do with that code aside from the standard icon, title, text:
Perform actions based on clicking the tooltip
Modify the tooltip that pops up over the icon in the system tray after loading it (to reflect changing values)
Multiple lines? (Not sure if this can even be done, really)
More information on other things you could do in a windows 7 environment versus XP (which seems to be what this was written for).
Ideally I'd get some sort of return value or some semblance of an event when the tooltip is clicked so that I could run some code, but currently I'm importing that code as a module and calling at various times, so I'm not sure how to handle clicks outside of the popup code itself...
Information on handling these things with python seems quite scarce. Thanks in advance.
Perform actions based on clicking the tooltip
Whats the problem OnTaskbarNotify? Hock yourself in there.
Modify the tooltip that pops up over the icon in the system tray after loading it (to reflect changing values)
Probably not, I am not sure about the WinAPI here. I haven't seen it in the wild, so...
Multiple lines? (Not sure if this can even be done, really)
With most WinAPI, just insert a \n in the string.
More information on other things you could do in a windows 7 environment versus XP (which seems to be what this was written for).
LOTS... But that is a bit vague... It depends what your needs are. But for kol feturez you need to google on your own...
On Linux and Unix systems I use the notify-send OS already implemented system.
import os
os.system('notify-send "'+title+'" "'+message+'")
Maybe in Windows there is some API32 for this.
Check this https://gist.github.com/wontoncc/1808234