I am beginning to work on a program in which i want multilingual support, but since it is pretty modular (and i want it to be even more in the future), a language change means "destroy what you had of interface and build again with the content which language modules have". (You can see the source as of now on GitHub)
This full-modular approach may give many problems, but i still want it, and so the problem is: Whenever i destroy the widgets i had, until i am alone with the raw Gtk.Window itself, i am not able to assign once again widgets to it. They won't get displayed at all, sometimes silently, sometimes with errors depending on my approach.
Lets suppose the class window, which inherits from a Gtk.Window.
This class is the raw window, and i assign to it a Gtk.Box -
self.interface.
self.interface itself, has two Gtk.Box's, one sidebar and one stack of contents.
To rebuild i tried to:
Change the language variable
Use the method destroy on self.interface, which removes the widget and its child's.
Reuse the function to build the widgets stack on top of self.interface
Re-add self.interface to self (window).
This approach returns:
g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Gtk.main()
Pointing to the .show_all() method in this file.
I've already tried to leave interface without using .destroy on it, applying only on its child's, and then creating them again over it, but didn't worked. The window was left blank with no error at all.
The code i am trying right now is:
#Remember, self is a Gtk.Window()
def __init__(self):
[...]
self.interface = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL)
self.stack = None
self.add(interface)
self.build_interface()
def build_interface(self):
self.interface.pack_start(
self.create_side_navigation(
self.interface_data["menu"][self.language]["name"])
, False, False, 0
)
self.stack = self.create_content_stack(self.interface_data["menu"][self.language])
self.interface.pack_start(self.stack, True, True, 0)
###Code to rebuild(this is a question dialog):
if response == Gtk.ResponseType.OK:
self.language = self.new_language["Index"]
self.new_language = None
self.stack.destroy()
self.interface.destroy()
self.interface = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL)
self.build_interface()
self.add(self.interface)
This code will cause the previously told "g_object_unref" error.
What is causing this? Why can't i add anything once deleted?
Feel free to clone the repo and try, the code is well commented(yet i am not sure if poorly written, i am a python newbie) and its quite easy to understand where is the problematic part. Its not too big.
PS: It should need GTK+3.12 because of the popovers.
As a GTK Dev showed to me, GTK has by default all the widgets invisible.
The error was caused in the line which declared the whole interface visibility (windowclass.show_all()), but since the interface changed since when it was applied, it threw that warning.
He pointed me to .remove() instead of .destroy(), and to set .show_all() to the new elements after set up.
The next commit(or the following) on that git, has the solution.
The best way to be multilingual is to keep your widgets the same and merely change the text of labels and titles. This can be done without disturbing the overall setup. For example:
s='Stop'
if lang=='fr': s='Arret'
...
somelabel.set_label(s)
Related
My GUI essentially wraps various backend PowerShell scripts that perform some automated functions. Kind of beside the point, but alright, here's where I'm stuck at.
I've got my interface designed in Qt Designer, outputted to a .ui file, converted to a .py file via PySide2-UIC, and a mainwindow class that is a subclass of the main window class I created in Qt Designer. All is well. No issues with any of that.
I'm now on to a part in my programming that I'm capturing form data from QWidgets (which is working) to a list. I've got a completely custom written class that is meant to handle taking that user input, setting other variables like filenames or paths to certain configuration files that are needed, and executing a subprocess PowerShell command with all of that information. Where I'm stuck at is trying to determine what the right place is to instantiate this custom object, inside my MainWindow class, outside my MainWindow class? But if so, where? Here's some simplified code to help explain my dilemma.
Interface Sequence
App start
MainWindow appears
User browses to form with input controls
User enters info like (IP address, username, password)
User clicks button that is connected to a method in the class
Method recurses through the child widgets on the page and captures info into a dictionary via finding qLabels and qLineEdit (buddies)
Questions:
How do I call the next method (only once even though the capturing of data is recursive)? I'm thinking about just connecting the signal to a second method that handles taking the captured data and sending/setting it into the custom class object. However, when I instantiate my custom object inside of the MainWindow class and I try to reference the object by self.customObject.sendUsesrInput(self.userInputVariable), PyCharm doesn't think self is defined inside this particular method. It doesn't properly highlight the word "self" like in the rest of the class definition, and it suggests that I need to import self.
Update
I was able to clear the errors around "import self" in PyCharm. It had something to do with improper spaces vs. tabs, even though I only ever use the tab key to do indentation. Might need to go and check my inpection settings closer. The other questions still stand though. Where is the best place to call methods on my custom class to "form a command", and "run a command", should that be executed by the mainWindow class, or should I set a flag on the customObject class that then triggers those other actions? Or more generally, should an object be in charge of executing it's own functions/methods, something tells me not usually, but I can't be sure. Also, if there are any books on the matter, I'd be happy to do my own research. I'm currently reading "Rapid GUI Programming" but not sure if this topic is covered in the later chapters just yet.
So I guess my question is, where do I handle the customObject class, in the mainWindow class, or in some other place? If so, where?
I apologize if this question is NOT clear. I promise to update as necessary to help work through this.
Here's come simplified code examples:
class customClass(object): # this is actually in a separate file but for argv sake
def __init__(self):
self.userInput = ""
self.file1 = ""
self.file2 = ""
self.otherstuff...
def setUserInput(self, uinput):
self.userInput = uinput
def dostuffwithdata(self):
# method to execute subprocess command
class MainWindow( QMainWindow ):
def __init__(self):
super(MainWindow, self).__init__()
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.customObject = customClass.customCmdClass()
self.cmddata = dict()
self.ui.toolButton.clicked.connect(self.getformdata)
def getformdata(self):
# recurses through QWidgets and grabs QLabels and QLineEdit.Text() and updates dict()
for w in widgets:
if w is qlabel:
k = w.text()
v = w.buddy().text()
self.cmddata.update({k: v})
""" all the above works fine. what doesn't work is this part"""
# at this point I want to send the collected data to the customObject for processing
def senddatatocustomObject(self):
self.customObject.setUserInput(self.cmddata) """but this says that 'self' isn't defined.
I know it has to be because of the object in an object, or something I'm doing wrong here.
**Update**: figured this out. PyCharm was freaking out about some sort of
perceived indentation error despite there not appearing to actually be one.
Was able to correct this. """
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
win = MainWindow()
win.show()
sys.exit(app.exec_())
In an effort to close this out, I offer this answer to my previously posted question about where to put the "logic" and flow in my code.
Given that this is a graphical application without any back-end services, it makes the most sense to put most of the user-interaction logic and flow within the MainWindow object because that is essentially the control center of my program. When a user clicks or enters something, it is going to happen on the MainWindow, when a state changes, it happens (mostly) on the MainWindow or is directly tied to the MainWindow in some way. Therefore, it makes sense to include the majority of my method calls, user-input-flow logic, and other code, in the MainWindow class/object of my program.
My other classes and objects are there to capture state and to perform actions on different sets of data, but in most cases, these auxiliary classes/objects will/should be controlled by the MainWindow of my application.
This is certainly not the only way to write this application or others, but I believe this at least answers my previously posted question(s).
I want to dynamically change the number of sliders on my application window, in dependence of the number of checked items in a QStandardItemModel structure.
My application window has an instance of QVBoxLayout called sliders, which I update when a button is pressed:
first removing all sliders eventually in there:
self.sliders.removeWidget(slider)
And then creating a new set.
The relevant code:
def create_sliders(self):
if len(self.sliders_list):
for sl in self.sliders_list:
self.sliders.removeWidget(sl)
self.sliders_list = []
for index in range(self.model.rowCount()):
if self.model.item(index).checkState():
slid = QSlider(Qt.Horizontal)
self.sliders.addWidget(slid)
self.sliders_list.append(slid)
The principle seems to work, however what happens is weird as the deleted sliders do not really disappear but it is as they were 'disconnected' from the underlying layout.
When created, the sliders keep their position among other elements while I resize the main window.
However, once they've been removed, they occupy a fixed position and can for instance disappear if I reduce the size of the window.
Unfortunately I'm having difficulties in linking images (it says the format is not supported when I try to link from pasteboard), so I hope this description is enough to highlight the issue.
Do I have to remove the sliders using a different procedure?
EDIT
Thanks to #eyllansec for his reply, it condenses a bunch of other replies around the topic, which I wasn't able to find as I did not know the method deleteLater() which is the key to get rid of widgets inside a QLayout.
I am marking it as my chosen (hey, it's the only one and it works, after all!), however I want to propose my own code which also works with minimal changes w.r.t. to what I proposed in the beginning.
The key point here is that I was using the metod QLayout.removeWidget(QWidget) which I was wrongly thinking, it would..er..Remove the widget! But actually what it does is (if I understood it right) remove it from the layout instance.
That is why it was still hanging in my window, although it seemed disconnected
Manual reference
Also, the proposed code is far more general than what I need, as it is a recursion over layout contents, which could in principle be both other QLayout objects or QWidgets (or even Qspacer), and be organized in a hierarchy (i.e., a QWidget QLayout within a QLayout and so on).
check this other answer
From there, the use of recursion and the series of if-then constructs.
My case is much simpler though, as I use this QVLayout instance to just place my QSliders and this will be all. So, for me, I stick to my list for now as I do not like the formalism of QLayout.TakeAt(n) and I don't need it. I was glad that the references I build in a list are absolutely fine to work with.
In the end, this is the slightly changed code that works for me in this case:
def create_sliders(self):
if len(self.sliders_list):
for sl in self.sliders_list:
sl.deleteLater()
self.sliders_list = []
for index in range(self.model.rowCount()):
if self.model.item(index).checkState():
slid = QSlider(Qt.Horizontal)
self.sliders.addWidget(slid)
self.sliders_list.append(slid)
It is not necessary to save the sliders in a list, they can be accessed through the layout where it is contained. I have implemented a function that deletes the elements within a layout. The solution is as follows:
def create_sliders(self):
self.clearLayout(self.sliders)
for index in range(self.model.rowCount()):
if self.model.item(index).checkState():
slid = QSlider(Qt.Horizontal)
self.sliders.addWidget(slid)
def clearLayout(self, layout):
if layout:
while layout.count():
item = layout.takeAt(0)
widget = item.widget()
if widget:
widget.deleteLater()
else :
self.clearLayout(item.layout())
layout.removeItem(item)
This is my first Question here at StackOverflow, so please be patient with me if some info isn't present or I missed something important, but anyways i'll do my best :)
Recently I started to code in Python2.7, so I'm not very good at it. While playing with PyGtk, PyGObject, Glade, etc I found something particular about switches (Haven't tried with any other widget, so I don't know if it happens somewhere else. Most likely it doesn't, I hope...)
I made a very basic GUI with a single "window" plus a "switch" using Glade
My objective was to deactivate switch after user tried to activate it if some exeption raised up before, something like:
Activate it --> * Found error --> * Deactivate it
I made some code, and after a while, I noted that THIS piece of code created a loop-like block, blocking GUI's window afterwards:
builder = Gtk.Builder()
window1 = builder.get_object('window')
switchie = builder.get_object('switchie')
switchie.set_active(False)
def Hi(switch, active):
print switchie.get_active()
switchie.set_active(not switchie.get_active())
switchie.connect("""notify::active""", Hi)
window1.set_position(Gtk.WindowPosition.CENTER)
window1.connect("delete-event", Gtk.main_quit)
window1.show_all()
If i'm right, "switchie.connect" links "switchie" object with "Hi" func whenever "switchie" gets clicked.
But if I execute this and try to turn switch on, GUI hangs up. I did try to execute this via script & command-line and adding the "print switch state", resulting in an endless loop (True & False)
I tried with many other funcs I made, but neither of them could solve this issue. In fact, this is the "essence" of all the other funcs I made.
Why does this happen?
Where's the loop?
Am I wrong in some line?
Help is appreciated!
(If you need to see the rest of my faulty funcs, just ask for 'em, but I don't think they'll help...)
You want to hook up the switch like this:
switchie.connect("""activate""", Hi)
This will only get called once for every time it is clicked. What you were doing is hooking up to the signal after it changed, so it was constantly changing, and never catching up. You will also want to change
def Hi(switch, active):
to
def Hi(switch, active = None):
for keyboard support.
I am building a “pseudo-intelligent” GUI for a gimp plugin using Glade. The main part of the GUI has two frames and imports the contents using the “reparent” method. The main objective is to have the contents of the second frame determined by the selections made in the first frame. (Eventually, the intention is to import this GUI as the content for the tabbed pages of a "notebook")
To start with, I made a simple window, consisting of a “RadioButtonBox” and a “ComboBox” which is populated using:
# create the cell renderer
self.cell = gtk.CellRendererText()
#populate the default choice into the Selection combobox
self.SelectionBox = self.builder.get_object("SelectionBox")
self.SelectionBox.set_model(self.EditCommands)
self.SelectionBox.pack_start(self.cell, True)
self.SelectionBox.add_attribute(self.cell, 'text', 1)
self.SelectionBox.set_active(0)
# End: populate the selection combo box section
This works and I can successfully “import” and “reparent” the simple GUI as the first frame of the larger, more complex GUI without any problems. However, as the design progressed, it has become more convenient to have the code for the first frame as an integral part of the main GUI, and this is where my problems begin.
I have reproduced the contents of the simple GUI in the first frame of the larger GUI and copy/pasted the code from the simple GUI's “init” function. In other-words, everything is identical.
Unfortunately, when I run the code I get the following error:
C:\Documents and Settings\anonymous\Desktop\Glade-tutorial\BatchEditMain\BatchEditLibrary\Tab.py:46: GtkWarning: gtk_entry_set_text: assertion `text != NULL' failed
self.SelectionBox.set_active(0)
Could someone please explain what the problem is?
Thanks in advance
Irvine
The GTK Warning is saying that somewhere gtk_entry.set_text() is being called with None instead of some text. This is happening in the call to self.SelectionBox.set_active(0)
This feels a little bit like gravedigging , but i stumbled across the same Problem today and this was the first post google showed...
With a little further research i found this Question:
How create a combobox on Python with GTK3?
The author seems to have the same error.
What in his and my case seems to do the trick is a simple:
combobox.set_entry_text_column(0)
Important it has to be in front of set_active(0)!
So in your case this would be:
...
self.SelectionBox.add_attribute(self.cell, 'text', 1)
self.SelectionBox.set_entry_text_column(0)
self.SelectionBox.set_active(0)
...
PS: Whatch out if you want to apply attributes like "foreground", they seem to get overwritten by set_entry_text_column(0) if set befor.
E.g: if items in the model look like:
["TEXT_YOU_WANT_TO_DISPLAY","TEXT_FOREGROUNDCOLOR_AS_MARKUP_COLOR"]
The change to the foregroundcolor can be applied with the following:
...
self.SelectionBox.add_attribute(self.cell, 'text', 0)
self.SelectionBox.set_entry_text_column(0)
self.SelectionBox.add_attribute(self.cell, 'foreground', 1)
self.SelectionBox.set_active(0)
...
The following code exhibits a problem I do not understand:
from Tkinter import *
root = Tk()
cheese_var = IntVar()
parrot_var = IntVar(value=1)
check_menu = Menu(tearoff=0)
check_menu.add_checkbutton(label="Cheese", variable=cheese_var)
check_menu.add_checkbutton(label="Parrot", variable=parrot_var)
count = 0
class Top():
def __init__(self):
global count
count += 1
self.tl = Toplevel(root)
Label(self.tl, text="Window " + str(count)).pack()
self.mb = Menubutton(self.tl, text="Push Me", bg='pink')
self.menu = Menu(self.mb, tearoff=0)
self.menu.add_cascade(label="Choices", menu=check_menu)
self.menu.add_command(label="New Window", command=new_top)
self.mb.config(menu=self.menu)
self.mb.pack()
def new_top():
Top()
Top()
root.mainloop()
The menu brought up by the menu button in the created top level window initially behaves as expected. Clicking on the New Window command there creates a new such window, which also behaves as expected. Indeed, as long as you keep creating new top level windows, everything continues to work as expected. However, once you delete (close) any one of those windows, then, in a subsequently created new window, the Choices cascade on the new menu is not functional. (It is still OK in the windows created before the closing of one.)
The situation in which I initially encountered this symptom was much more complex, but I was able to simplify it down to the above example which exhibits the issue. I have discovered that I can avoid the problem by having each instance of Top create its own check_menu as an attribute; but I do not understand why this should be necessary. Please point me the way if there is one to avoid the problem without such replication of a cascade menu used in multiple windows.
Unfortunately, I don't think it is possible to do what you want. I'll try to explain as best as I can.
When you first run the script, check_menu is created and works fine for the first window. As you create more windows, check_menu is simply shared between them. However, when you close one of them, check_menu (and everything under it) is destroyed. So, when you create a new window after that, check_menu no longer exists and it doesn't show.
However, the script doesn't throw an error because, for some reason, Tkinter allows you to assign menus to things that aren't menus. Believe it or not, none of the following code:
self.menu.add_cascade(label="Choices", menu=None)
self.menu.add_cascade(label="Choices", menu=1)
self.menu.add_cascade(label="Choices", menu="")
will break the script. Each line simply does nothing but create an empty cascade "Choices".
That is basically what is happening. After closing one window, check_menu and everything under it is destroyed. Yet, Tkinter doesn't throw an error but instead assigns a menu to something that is no longer a menu (as far as what it is assigning the menu to, I believe it is using the old instance of check_menu, which was destroyed).
To solve this problem, recreate check_menu and everything under it each time you call Top. In other words, put the code for check_menu (and its options) in the __init__ method of Top. That way, each time Top is called, check_menu will exist.
Hope this helps (and that I explained it sufficiently :)