Kivy threading Here is what I I do not understand how to combine multiprocessing with Kivy, a Python GUI library, so please help me on this. It works fine, however the loading time is quite long (~5 sec. As python is not able to run these threads on different Cores due to the Global Interpreter Lock, I would have liked to try to use PyPy for it and see if I can make the threads run faster of different cores since PyPy is different and offers stackless (what ever that is?. Follow answered Oct 5, 2022 at 3:03. RESULTS. clock import Clock, _default_time as time # ok, no better way to use the same clock as kivy, hmm from kivy. So that line will never be drawn. I've some problems with python(threading) and kivy: Here is some code: import kivy import threading import time from kivy. gridlayout import GridLayout from kivy. These are my numpy functions combined You can use my widget the same way you use ProgressBar, except you have to call set_value(value) whenever you want to set one (check the example I've provided). The background thread updates the texture in the Image Widget main class. Python kivy and multiprocessing bug. If you are new to threading. 3,296 views. get_color_from_hex Button: text: 'doit' on_release: In Python, threads cannot be killed directly due to the design of the threading library and the underlying complexities of safely terminating a thread that might be holding resources or locks. 2 How do I update the GUI from another thread? using python. Thread. Clock intervals, but nothing seems to work. t1 = threading. create_lifecycle_aware_trigger`) for scheduling callbacks that raise a Kivy multi-threading and update screen. Core. I have updated the code to be able to use threads instead of processes, which works. Thread(target=app. The problem is that the texture variable gets updated but is not displayed in the kivy Gui app. clock import Clock import time, threading class PopupBox(Popup): pop_up_text = ObjectProperty() def update_pop_up_text(self, p_message): self. texture = texture1 with a Clock. 0, 'y': ButtonY}, on_press=start) Or if you have any suggestions how this can be better done or how it should be done i would really appriciate it im really stuck on this I have to divide long tasks into threads. Viewed 5k times 2 . Regarding the separation, just make a new module to put the class there and import it wherever you want to use it. import threading from kivy. Creating thread anywhere in Kivy app makes the whole app wait for end of the thread function, so there is no difference when using threads or not. 6. This is for system stability. 11. 0, all the events scheduled for the same frame, e. I want to disable buttons until Time_consuming function finishes, and then enable button again. 0 How to make Kivy app run inside a thread? Load 7 more related questions Show fewer related questions Sorted by from kivy. By the way in the thread I suggest making the target: Threading and Callback Order¶. Kivy GUI (Python) falling into a segmentation fault when trying to update the screen. source code: https://github. I managed to get the thread issues working, but then I found that the threads (up to 4) were all running on 1 core (not 4). 2. clock import Clock main_kv = """ <CustomLabel>: size_hint: (None, None) size: kivy app freezes when using threading. Add a comment | Your Answer The goal is to have one thread that constantly polls the MIDI input and routes events to pyfluidsynth, while a conventional Kivy app is running in parallel. properties import NumericProperty, ObjectProperty from kivy. app import App from kivy. Event is a thread-safe boolean variable flag that can be either set or not set. ) should be done only in the main thread. I'm fairly new with Kivy and kivyMD, and even more with threading and shared resources. label import Label from time import sleep import threading class MyApp . Personally, when I use a second thread, I use a queue for the inter-thread comm as follows: from Queue import Queue class KivyQueue(Queue): ''' A Multithread safe class that calls a callback whenever an item is added to the queue. Does somebody have some information to Your modified code still is not really using multi-threading, because your new coll() method simply schedules the another() method to run back on the main thread. username. utils. Kivy > Threading and using the Spinner 1 KivyMD//Python How to create a loading dialog box (pop-up) that displays a spinning wheel while the code runs another function in the background I'm trying to use numpy-based functions corroborate with Kivy, but once these functions are called on_enter a Kivy Screen, the app freezes, and consumes so much CPU and RAM. 1 Updating Kivy Label Using Threading. – John Anderson I am trying to make a application using Kivy that use threading. This example shows us how to use Clock or the mainthread Kivy multi-threading and update screen. This allows you to create responsive and interactive applications that perform well even when executing long-running tasks. I have looked into threading and the Kivy. Run Flask application with Jython. load_string(""" <TextWidget>: BoxLayout: orientation: 'vertical' size: root. Check here for info on python threading in a I'm having trouble with the threading in Python and Kivy. How to run two process at once using kivy. Kivy - automatically start a method from popup. Often, the Popup displays very badly. Think of it as your main entry point into the Kivy run loop. Lock() to lock the thread with the popup_B: the popup_A appears over the popup_B. Use publisher/consumer model as described here. I think you just need to remove the from that method, so that the target is set to the process_some_data method and not its I'm completely a newbie to kivy and have been learning python for only last one and half month, without any programming knowledge. Kivy and Flask threads blocking each other in Python2. start() t1 Application¶. current = 'menu' line and move it to, for example the thread_notice function. base import EventLoop from kivy. Cannot reproduce this with a simple click to display Popup, but using some threading shows it up Kivy is an open-source Python framework for developing cross-platform graphical user interfaces (GUIs). Two Flask Applications at same time. How to kivy app freezes when using threading. Label, TextInput and some others. def run(self): engine = OpenGL related operations (widget, canvas, property manipulation etc. triggering Popup. Instead run your ui on your main thread and run your other app functions on a secondary thread. open() method to redisplay a hidden dialog. text) and be done with it. process_some_data()) runs the process_some_data() method, then sets the target of the created thread to the return of that method. What I know is that Kivy GUI can not update until my func_call has ended, but in my case, it can take hours to end. 1 - KivyMD 0. by clicking on the button named button it should launch the popup on another thread with a progress bar that evolves after 3 seconds. Networking: Kivy provides support for networking, allowing developers to create networked applications that can I'm trying to build the most basic Hello World kivy apk with buildozer and it keeps failing to build. The Clock now has a ClockBaseBehavior. properties import ObjectProperty from kivy. 7. How to fix kivy not responding while give it another task. 1. text = p_message class ExampleApp(App): def show I do not understand how to combine multiprocessing with Kivy, a Python GUI library, so please help me on this. The Result Screen then populates its GridLayout widget with widgets called 'Basers'. You even do Displaying something in kivy while a process is running background; Kivy: how to display a widget while waiting for another one to be displayed t1 = threading. How to run a Method on the exit of a kivy app. Once the threaded function (that isn't the animation) is done it switches screens to the 'Result' screen. So far I have tried with: Using mutex = threading. Nothing in Kivy should sleep. The here's the code I have used ObjectProperty to trigger update both label:text and the Image:Texture But only the Label:text Kivy is deisgned such that only the main thread in a Kivy app can modify the GUI. kivy run_on_ui_thread crash. Kivy is based on Python and uses Sphinx for documentation, so the documentation for each class is in the actual file. 0. What am I doing wrong? kv file: BoxLayout: Button: on_press: threading. Using the Thread will work. Prevent pyttsx3 from freezing the GUI. join() the program just freezes and the when interacted with it does not respond. Kivy: Popup is blocked by main thread. Kivy multi-threading and update screen. properties import ListProperty from kivy. label import Label. #-*- coding: utf-8 -*- from kivy. How close kill a task started with asynckivy in Python3. from kivy. async_tick() and ClockBaseBehavior. Kivy Popup misbehaviour when called from inside 'on_enter' 1. I suspect it is because they can't coexist in one thread process, so I tried Multithreading, but the app still crashes. So when ever I face a problem I try to start from the very basic level like I can use this threading system in tkinter in any manner now but initially I started with only a simple number counter that will change the label everytime when I had this code which uses threading but at some point, the GUI freezes (after I pressed the button). This will automatically update both circular and text progression. Thread(target=self. This if done properly and for the correct use case can be very effective in improving performance. In Summary, I want my code to be ran when I press a button, and my code execution to not be hindered. Ask Question Asked 8 years, 10 months ago. Initially, I had created a code using Kivy, a Python GUI library, and threading. . Kivy widgets connected unexpectedly. start() def other_func(a, b): # your code here Kivy needs to be in it's own thread. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company Kivy and Python threading - how get data between them. The only exception to this is scheduling a callback for execution with Clock, this is a thread-safe operation. Just create the table, fetch the data in another thread and set the row_data attribute to the fetched data. daemon = True # start the thread t. Kivy unresponsive and unable to change text in a textbox. compat import queue from threading import Thread class _Worker (Thread): '''Thread executing tasks from a given tasks queue ''' def I've tried adding @mainthread to my create_grid function as suggested here: Avoid : Cannot create graphics instruction outside the main Kivy thread but it's still freezing the app. press() There is no way to update the user interface or create widgets in a thread as kivy doesnt garuntee stable behaviour in this way. And replace the self. This example shows us how to use Clock or the mainthread decorator to perform these actions, and how to use threading events to stop hanging threads when the app is about to close. text = <string 2> What you are asking is from kivy. Improve this answer. However, you can implement a thread termination mechanism using a flag that the thread checks periodically to decide whether to exit. textinput import TextInput from kivy. Running multiple Kivy apps at same time I am making an app in kivy for that i am using linux. 0. Despite this unfavorable limitation, a companion thread would suffice for other non-kivy event processing and interacts with kivy UI through Threading and Callback Order-----Beginning with 1. Here is an example of an app I created that uses threads: from kivy. ). Modified 7 years, 4 months ago. Try start the thread in the init method instead. Just call the MDDialog. class threading in kivy example. kivy app freezes when using threading. Concurrently running a You must specify a default loading image when using the loader:: from kivy. 1. 3. author: dessant; kivy: >= 1. In Kivy you can easily access e. import threading import Queue from kivy. all the events scheduled in the same frame with a ``timeout`` of ``0``, well be executed in the order they were scheduled. I'm trying to create a small GUI with kivy. How to fix kivy not responding I'm trying to use numpy-based functions corroborate with Kivy, but once these functions are called on_enter a Kivy Screen, the app freezes, and consumes so much CPU and RAM. E. If you want to try something different you can use kivy clock # dt means delta-time def my_callback(dt): pass # call my_callback as soon as possible (usually next frame. init_completed) def init_completed(self, dt): t = Thread(target=animate_image, args=(self)) t. This example shows us how to use Clock or the mainthread decorator to perform these actions, and how to use threading events to stop hanging threads when the app is about to close. Beginning with 1. The issue now is that I need to find a way for each process to update the original screen. You can solve this two ways. Kivy widget generation very slow. How to stop a thread after the task is finished in python? Hot Network Questions What do "messy" weapons I modified your example a bit. But doing this is usually bad practice (doing blocking calls without a thread, or waiting for the thread to finish in a blocking way, which is equivalent), what you want, instead of waiting for the task to be done before proceeding, is to As @JohnAnderson mentioned in the comments, the solution for kivy is to use threading. Kivy is built on top of the OpenGL graphics engine, which provides fast and responsive graphics Although most of this answer is both factually accurate and useful, one particular statement is simply untrue: "You cannot reuse an MDDialog anyway. Pop up Kivy displaying while a process is running in background. One important thing to note here is the way packages/classes are laid out. The App class is the base for creating Kivy applications. png') You can also load an image from a url:: # # Try to use pygame as our first choice for loader # from kivy. label import Label from kivy. Kivy does not play gif in Popup Kivy multi-threading and update screen. clock import Clock def animate_image(self): anim = Animation() anim. size Button: from kivy. 8. lang import Builder Builder. I've been stuck in this for days. The popup_B runs together with a method in a thread otherwise Kivy does not show the popup (locking GUI). b. start() Button: on_press: app. When I try to end a thread with the function . schedule_once(self. I think it's an issue with at the end of this video u will have a general understanding of why we use threads in Kivy and how to use them. How to make Kivy app run inside a thread? 0. Thread I'm trying to make a chat application based on client-server. behaviors import Python 3. pop_up_text. properties import Threading and Callback Order¶. run() method. button import Button class This example shows us how to use Clock or the mainthread decorator to perform these actions, and how to use threading events to stop hanging threads when the app is about Compare Working with threads in kivy. Also the GUI gets garbled. window import Window from threading import Thread Resolution = Usually bind list should contain all Kivy properties used in getter method. lang import Builder from kivy. However, while it almost solves my problem, the answer assumes I know more about Kivy than I do; I don't know how Threading and Callback Order¶. Draw, you do that with a new MyWidget object, and not the one you returned in your build method. I can successfully start the thread but can not end it. Events, you can learn more here: How to Use an Event Object In Python; A new event can be created and then shared between threads, for example: it's not obvious to me which graphics operations have to be done in the Kivy thread Nothing is safe from outside mainthread, you literally can not do anything safely from another thread. loader import Loader image = Loader. 153 7 7 bronze badges. __init__(self) self. network. another thread may request a callback in kivy's thread and then process some result. open() (kivy) 1. Nothing in Kivy should do blocking IO. This is useful for handling time-consuming tasks like network requests, file I/O, and complex These are my numpy functions combined with the Thread module. schedule_once() (or just add the @mainthread decorator to that new method). Modified 7 years, 5 months ago. :: with safe: foo() Any use cases besides compacting code? ''' __all__ = ('SafeMembrane', 'InteractiveLauncher') import inspect from threading import Thread, Event from kivy. When the client receive a message I want to display it on my kivy screen. ids. def __init__(self,name): threading. popup import Popup from kivy. Struggling to implement threading in kivy app. GitHub Gist: instantly share code, notes, and snippets. Kivy provides a thread-safe API that enables you to spawn new threads and safely update the user interface from those threads. Hot Network Questions Covering a I have a kivy application in python which uses some threads. there is a Time_consuming function and when it runs, kivy ui will goes in black, so I used Threading. I need some sort of parallel process, or else the Kivy UI freezes for as long as the midi poll while loop is running. It is designed to make it easy to create applications that can run on multiple platforms, including Windows, macOS, Linux, iOS, and Android. start(self. Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company How to implement threading when building buttons with Kivy in my class And a separate thread on buttonpress when calling start in :text="START",size_hint=(SizeW, SizeH), pos_hint={'x': . 5. __init__(*args, **kwargs) Clock. Here is a modified version of your code that uses threading. Thread, as follows. utils import deprecated def safeWait (dt): EventLoop. While the complexity of the thread looks manageable, Sooner or later you will be bitten with buggy non deterministic behaviour and or in this code I'm making a simple counter that counts and updates the label lets say 0-9 and it should update the label everytime but the app freezes and only updates when the I am wrote a piece of python code that handles multiple processes and it works great, but I am trying to add a Kivy based display to this code. Also, all the Kivy offers now, since ``1. Today, I fill in the 3 MDGridlayouts (sbgridfamily, sbgridgender, sbgridspecies) sequentially with SmartTileWithLabels. It can be shared between threads and checked and set without fear of a race condition. If the content of your loop executes fast, you can just use Kivy's Clock object to run your function instead of looping: Is it possible to have a main control/adapter thread that opens a thread for kivy and a thread for model operations? The @mainthread is not necessarily the main thread but the thread that creates the kivy app to run. schedule_once() call. Instead of Then you should use the threading, but the parts that create GUI widgets (or display them) should be moved to another method and that new method called using Clock. test()). urlrequest import UrlRequest req = UrlRequest (url, on_success, on_redirect, on_failure, on_error, on_progress, req_body, req_headers, chunk_size, timeout, method, decode, debug, file_path, ca_file, verify) This method is intended to be used in the main thread, and the callback will be dispatched from the same thread from which you’re calling. The async library to use is selected with How to make Kivy app run inside a thread? 0. 0 kivy app freezes when using threading. Ask Question Asked 7 years, 8 months ago. To optimize this loading, I ok, I can ,look closer. In most cases, you subclass this class and make your own app. I am wrote a piece of python code that handles multiple processes and it works great, but I am trying to add a Kivy based display to this code. loading_anim) class LoadingWindow(Screen): def __init__(self, *args, **kwargs): super(). boxlayout import BoxLayout from kivy. Because when you do MyWidget(). But if you've called a function with multiple lines, and in one of the lines Open source UI framework written in Python, running on Windows, Linux, macOS, Android and iOS - Working with Python threads inside a Kivy application · kivy/kivy Wiki That is have Kivy run in the main thread then dispatch other tasks to another thread. I suspect it is because they can't coexist in one thread process, so I tried Multithreading, but the app still crashes. You cannot do any kivy instructions outside of the main thread, which means you cant run sendNotice on a diffrent thread becuase it has kivy code in it if my_big_chunk_of_code() takes time then remove the kv. Viewed 1k times 5 I'm relatively new to kivy and am having an intermittent issue with certain images and button images not loading correctly, even when the same image loads correctly for other widgets using the same image. deamon = True Why bother with a Thread if you are going to wait for it anyway? You could just call send_data(self. factory import Factory from kivy. Similarly on line 5: from kivy. event import EventDispatcher import time import threading class Count: """ This is the external class we want to bind attributes from, this could be an imported module also. 10. But the line in another widget which is not on the screen. . Trying to draw a line with Kivy and threading. Here's an example from that link modified to use separate threads: from kivy. 104. Default Clock ^^^^^ The default clock In your run_thread() method, the line:. all the events scheduled in the same frame with a timeout of 0, well be executed in the order they were scheduled. I'm trying to implement threading in my kivy app. Kivy allows any thread "read-only access," so any thread can read from the GUI widgets and variables. The function I am trying to call with the thread does operations outside of the kivy gui like recognising speech with the speech recognition module. Share. For plotting there is Graph in the Garden, which will make your life easier if you don't want to play with graphic instructions alone - it's a nice practice though. Related. The threading technique is something I do a ton of in my applications and I have many in each application. ) Experimental async support has been added in 2. com/TirrouOussama Your modified code still is not really using multi-threading, because your new coll() method simply schedules the another() method to run back on the main thread. image('mysprite. 4 - Kivy 1. 4 and I'm sure I have all the dependencies, I keep getting the same error: Developing a detailed game using Kivy and using popups for some player interaction. dismiss() in a method which didn't call Popup. How to correctly use kivy graphics context instruction. button import Button from kivy. 0``, multiple clocks with different behaviors. clock import Clock import sys, threading, os, time from socket import * class Out_Come kivy app freezes when using threading. clock import Clock from kivy. I have updated the code to be Kivy supports multithreading, which allows developers to run multiple tasks concurrently. Thread(target = popup, args = (boxTitle, boxLabel)) t2 = threading. If the event is not processed in Kivy's thread because the app stopped, the second thread may block forever hanging the application as it exits. Everytime I try I get this error: **TypeError: Cannot create graphics instruction outside the main Kivy thread** I know why is this happend, but I dont know how to solve it. George Wilhelm Hegel George Wilhelm Hegel. I thought I could use threading on the popup but then the main app would still freeze and I assume best practice would be to have the heavy process on the thread and the popup on the from threading import Thread # the function that the button executes def button_press(): # create the thread to invoke other_func with arguments (2, 5) t = Thread(target=other_func, args=(2, 5)) # set daemon to true so the thread dies when app is closed t. " You can (and frequently should) reuse MDDialog widgets, actually. For example, in python fileA I am running a scanner function which basically first init the sensors and then start scanning. core. start() t2. popup import Popup import time, threading kv = ''' #:import hex kivy. e. async_idle() coroutine method which is used by the kivy EventLoop when the kivy EventLoop is executed in a asynchronous manner. dismiss() method to hide a displayed dialog and the MDDialog. The solution is to schedule callbacks with kivy's Clock that will call a function from kivy's main thread and do the work for you. To actually use multi-threading, put the guts back into the coll() method, so that it is actually run in a new thread. the kivymd app freezes when adding a large number of widgets. When used, the kivy clock does not block while idling. kivy glitch with images and threading. Can someone explain to me, why there are 2 threads (Thread-1 & Thread-2) active when I have only set one thread : (my_thread)? from kivy. Then after the scan is completed, it again starts scanning. I had to make a few changes just to get your code to run: from kivy. 0; OpenGL related operations (widget, canvas, property manipulation etc. Flask App that uses another standalone app? 7. So in my case the solution is probably to have the code in the thread add a Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; OverflowAI GenAI features for Teams; OverflowAPI Train & fine-tune LLMs; Labs The future of collective knowledge sharing; About the company I need to run a function from a python fileA which will update the label in the kivy app. text property in widgets that has this property i. Kivy: Popup not displaying. All Kivy GUI updates are done from the main thread, so if you block it, nothing in the GUI will update. name=name. mylabel = Label(text=<string>) mylabel. open() (kivy) 2. Basically, when I click a button and the screen switches to the next one, I want to launch a thread, and when I click the 'back' button, the thread should stop. user. g. I've tried on two different machines running Solus with Python 3. After a LOT of Google searching, the only thing I've actually found that approaches being useful, is an informative note here on StackOverFlow. If you return True it will cause a dispatch which one should do when the property value has changed, but keep in mind that the property could already have dispatched the changed value if a kivy property the alias property is bound was set in the setter, causing a second dispatch if the setter returns True. Also, all the scheduling and canceling methods are fully thread safe and can be safely used from external threads. But kivy gives me an Could be re-written with a context-manager style i. Running Kivy App inside another python program. Thread(target = time_consuming_method) t1. Threading Problem Kivy image texture not updating when threading is used. Please help me with it!! Client Class: Kivy multi-threading and update screen. screenmanager import ScreenManager, Screen from kivy. The issue is that attempts to modify the GUI from a seconday thread fail SILENTLY. i am getting a problem to update the progress bar gui using from kivy. uix. Basically a never ending loop. Consequently, we provide a API (:meth:`CyClockBase. Python tkinter popup not opening prior to subthread. So I am believe that I need to change over to use processes instead of threading (around line 582). New in version 1. progressbar import ProgressBar from kivy. You create an instance of your specific app class and then, when you are ready to start the application’s life cycle, you call your instance’s App. These Baser widgets are produced from a loop inside the python code since the number of widgets produced and information they show and hold depend on the result from the I am using kivy for UI. A threading. jjkkl klgcf mvqhpk nvqz nzh mehcqm qens tjitj shy pru