Event Handler Puns

it tell me the script mess up or missing images??

https://preview.redd.it/w8k5yg2vxxc81.png?width=990&format=png&auto=webp&s=c01b2aa1bdff26b9321cf3285bc02793a9dbd638

CODE

So basically none of the commands work, ready event works, messageCreate doesnt
anything i can do to it?

ready.js

messageCreate.js

ping.js

Is it possible to set up event handler rules globally through the root ADOM and have the non-root ADOMs inherit them?

Or are they really completely separated?

I would say I am fairly ok with React, however there's just one thing that always gets me mixed up, which is in what form exactly am I supposed to pass functions to event handlers.

For example let's say I have:

const handleClick = () => { doSomething(); }

I either do:

<Button onClick={handleClick} />

or

<Button onClick={() => handleClick()} />

What is the difference? I've just been interchanging them frequently when one seems to give weird behavior or not work and the other works fine.

The following is non-functional, but you should get the point:

require 'gtk3'

window = Gtk::Window.new( 'Demo' )

window.signal_connect( "motion-notify-event" ) { |widget, event| my_func }

str = 'hello'

def my_func()

puts str

end

Gtk.main

When code like this runs, you would get an error when the code hits the puts line saying that 'str' is undefined.

So my question is what kind of context is the event handler my_func() executed in that means it doesn't have access to 'str'?

1. Why do I have to make 'str' global ($) to make it work?

2. How to I pass some kind of context through to the event handler?

I'm struggling with the Ruby GTK documentation (or lack of).

The game in question is the Minecraft Java Edition, thanks to gamepass. To my greatest disappointment I cannot start the game because it crashes on loading a save inmmediately.

This issue is supposed to be the exact problem, and from the logs it does seem like it fails on opening a socket, but I do not have Avast and I tried turning off the firewall as well as forcing the JRE to use IPv4.

But to no avail. It is still happening. I am running an updated fresh W11 install.

I'm wondering if I should route my Blog.js to render on button click instead of opening another window in an event handler. I want the Blog.js to render in App.js when button is clicked but it still duplicates App.js into the new window. My code

Newbie to go lang(and for reddit too). implemented a basic multi connection supporting server side event handler in go. Looking for suggestions and feedback.

package main

import (
	"fmt"
	"io/ioutil"
	"log"
	"math/rand"
	"net/http"
	"strconv"
	"time"
)

func hello(w http.ResponseWriter, r *http.Request) {
	log.Printf("listening to client")

	messagec := make(chan int)

	go func(channel chan int) {

		defer func() {
			if r := recover(); r != nil {
				fmt.Println("recovered", r)
			}
		}()

		for {
			if channel != nil {
				message := rand.Intn(100)

				channel <- message
				time.Sleep(2 * time.Second)
			}
		}
	}(messagec)

	w.Header().Set("Content-Type", "text/event-stream")
	w.Header().Set("Cache-Control", "no-cache")
	w.Header().Set("Connection", "keep-alive")
	w.Header().Set("Access-Control-Allow-Origin", "*")

	defer func() {
		close(messagec)
		messagec = nil
		log.Printf("client connection is closed")
	}()

	flusher, _ := w.(http.Flusher)

	for {

		select {

		case rnum := <-messagec:
			if rnum%3 == 0 {
				fmt.Fprintf(w, "event: foo\n")
			}

			if rnum%5 == 0 {
				fmt.Fprintf(w, "event: bar\n")
			}

			fmt.Fprintf(w, "data: { \"msg\": \"%s\" }\n\n", strconv.Itoa(rnum))
			flusher.Flush()

		case <-r.Context().Done():
			return
		}
	}
}

func home(w http.ResponseWriter, req *http.Request) {
	content, err := ioutil.ReadFile("index.htm")
	if err != nil {
		fmt.Println("Err")
	}

	fmt.Fprintf(w, "%v", string(content))
}

func main() {

	http.HandleFunc("/", home)
	http.HandleFunc("/hello", hello)

	log.Fatal("HTTP server error: ", http.ListenAndServe("localhost:3000", nil))
}

See https://github.com/viksrirangam/sse-go.

Why do we pass a function reference for onSubmit but an anonymous arrow function for onClick? Would we do this incase handleSubmit function is to large to have inside the form? Also, how does onSubmit invoke handleSubmit if there are no parenthesis? As in, why is it not written as handleSubmit()?

return (
<form onSubmit={handleSubmit}>
    <label htmlFor='name'>Name:</label>
    <input name='name' type='test' />
    <button type='submit'>Submit<button>
</form>

// **** VS *****


  return (
      <button onClick={() => setState(!state)}>{state ? 'ON' : 'OFF'}</button>
  );

Annoying little thing, say I either accidentally add one, or add one but change my mind and don't want it anymore, it's alwyas there in the list of handlers I can add to an event.

So at the minute, I have 2 wxnotebooks. I added a page change handler for one, but the wrong one, so I unselect it and added a handler on the correct notebook. I also deleted the function it'd put in, because I didn't want it (at the time).

Now I'm later in my program and want to add a page change handler for the second one. I can still see the old handler I created, but when I select it, it scrolls me to where the code used to be, but it's deleted. Now I know I could just replace it but I'm OCD like that and I want it to put the function in for me. I also don't want my available handlers list filling up with non existant handlers.

So how do I remove them from the list, rename them and such? there must be a way I just can't see it. Or is adding a new handler essentially an un-undoable action that would require me to edit the wxwidgets generated code, which I hate doing because I never know when modifying my widgets will remove my changes.

I am facing this problem with an ESP8266, but since I am using the Arduino framework, I think the problem is the same for Arduino. I was trying to move the servo inside of the event handler callback for an incoming ESP NOW message. The callback calls the function below if the received message requests it.

This does not work. It seems that delay is ignored when it is run from the ESP NOW handler (works fine when directly called from the loop()). And come to think of it, delaying within the handler may disrupt the working of ESP NOW. If it were C#, there is something like async event handler. Is there any elegant way to achieve this? I have seen the "NoDelay" and "AsyncDelay" libraries, but they were either doing something in a loop (like blinking) and inside of the loop(). In my case, move() is not supposed to be called in a loop but only once the message is received, and it is not called from the loop() but from the ESP NOW library.

void move()
{
	servo.write(120);
	delay(300);
	servo.write(0);
}

The only way I could come up with is just setting a global variable in move():

void move()
{
	moveRequested = true;
}

And then check that in the loop(), check that variable to do initial write(), then set another variable to check the passed time, etc. It would probably work, but that 3 lines of coherent code is now scattered all over the place, and is difficult to understand. I wonder if there is a better way.

void loop()
{
	if(moveRequested)
	{
		moveRequested = false;
		isHandlingMove = true;
		servo.write(120);
		moveDelayStart = mills();
	}

	if(isHandlingMove)
	{
		if(mills()-moveDelayStart>=300)
		{
			isHandlingMove=false;
			servo.write(0);
		}
	}
}

Hi everyone,

I was hoping someone would be able to help point me in the right direction. I'm writing an event handler firehose endpoint for my API and want to be able to define a mapping of handlers and use a function to extract and execute the function. I have the code setup but i'm getting a type error when trying to invoke the handler function with the event .

I get the error: The intersection 'CreatedUserEvent & DeletedUserEvent' was reduced to 'never' because property 'type' has conflicting types in some constituents.

Here is the code, would really appreciate any pointers in the right direction

const CREATED_USER = 'Created User';
const DELETED_USER = 'Deleted User';

interface CreatedUserEvent {
  type: typeof CREATED_USER;
}

interface DeletedUserEvent {
  type: typeof DELETED_USER;
}

const createdUserEventHandler = (event: CreatedUserEvent) => event;
const deletedUserEventHandler = (event: DeletedUserEvent) => event;

interface Events {
  CREATED_USER: typeof CREATED_USER;
  DELETED_USER: typeof DELETED_USER;
}

const events: Events = {
  CREATED_USER,
  DELETED_USER,
};

interface Handlers {
  [events.CREATED_USER]: typeof createdUserEventHandler;
  [events.DELETED_USER]: typeof deletedUserEventHandler;
}

type HandlerTypes = Handlers[keyof Handlers];

const handlers: Handlers = {
  [events.CREATED_USER]: createdUserEventHandler,
  [events.DELETED_USER]: deletedUserEventHandler,
};

type EventNames = Events[keyof Events];

const eventMapping: Record<EventNames, HandlerTypes> = {
  [events.CREATED_USER]: handlers[events.CREATED_USER],
  [events.DELETED_USER]: handlers[events.DELETED_USER],
};

const getHandler = <E extends EventNames>(event: E): typeof eventMapping[E] => eventMapping[event];


const useHandler = (event: CreatedUserEvent | DeletedUserEvent) => {
  const handler = getHandler(event.type);

  // this line errors
  handler(event);
};

export default useHandler;

Hi all, new to React. Where do you guys put your event handlers?

Say I have a button component that needs some data for its onclick event from its parent/container component. Should i put the event handler in the button component itself?

OR

Should I put the handler up high in the parent/container and pass the handler as props to the button?

Edit: Also, what if the handler is setting a state in the parent/container component?

Thanks.

code_screenshot[https://imgur.com/a/yN0kC12]code gist [gist]

I am working on a project which takes in user input from the 'on click event.' Once I initialized the mpl_connect I assumed that it would keep listening to on click event until it I finally disconnect with mpl_disconnect. But this isn't the case. The code keeps running lines even after event handler is initialized.

The code works if I put 'input()' on line 117 because it stops further execution. This allows event handler to check 'on click' events. But now when the event handler is stopped I have to put text in input so as to continue code execution.

Other methods which I have tried are

1. Using a while loop to check if changes have been made to the variable which has to be changed in the on_click function.
2. Using while loop and time.sleep()

Both of the above method stops event handling and my matplotlib window crashes.

Any help would be appreciated.

Edit: While condition: plt.pause() does what input was doing and fixes the problem for me.

As in:

https://m.youtube.com/watch?v=i_iKKjepQKA

It isn't explained why you wouldn't just delete the line rather than commenting it out.

Hey guys, I am just wondering how to add parameters to event handlers? I am getting weird behaviour.

https://jsfiddle.net/t84j0wfk/7/

https://jsfiddle.net/o68z930b/

The first link alerts "hi" upon opening it, but not when you click the button. The second link alerts hi when you click the button? Why is that?? I need to pass parameters to my event handler but it just gets called straight away. Any help would be appreciated!!

edit: To anyone reading this, you just add .bind(Event, param) to the function name. Otherwise, the function just calls automatically. I don't get why though so if someone can explain that to me, that would be great!!

Hi, I have applied an onClick event on a href tag but it applies to each element of an array. How to avoid that and apply it to only targeted link/button. Here is a Codesandbox: https://codesandbox.io/s/amazing-lumiere-6vq3x?file=/src/App.js

Here is the code:

export default function App() {
const [active, setActive] = useState(false);
const Headings=["1. Heading", "2. Heading"];
const Subheadings=["1. Subheading", "2. Subheading"];

const handleClick = (e) => { e.preventDefault();
 if(!active){
     setActive(true)
     }else{
     setActive(false)
 }
}

const handleSub = (e) => { e.preventDefault();
}

return (
 <div className="App">
{Headings.map((val, index) =>(
 <ul key={index}>
      <a href="/#" role="button" onClick={(e)=>handleClick(e)}>
{val} </a> {!active ? [Subheadings.map((val, index)=>(
 <ul key={index}>
          <a href="/#" role="button" onClick={(e)=>handleSub(e)}>
{val} </a> </ul> ))] : null}
      </ul>
  ))}

</div>
); }

I'm working on a child component and I'm calling setState from an event handler within that child component. However, when I call setState to set a state variable in this scenario, the constructor of the component gets called which essentially resets that state variable back to the default value. Looks like calling setState in the child component re-renders the parent component, which in turn re-renders the child component. Is there a way to code around this scenario?

I had this weird problem, that after I successfully fetched and called setState for the status- and the data-values, rendering them would throw an error, because data was still undefined:

function SomeComponent({ url }) {
  const [status, setStatus] = React.useState("idle");
  const [data, setData] = React.useState(null);

  React.useEffect(() => {
    if (!url) return;

    fetch(url).then((data) => {
      setStatus("success");
      setData(data);
    });
  }, [url]);

  return <div>{status === "success" ? data.id : null}</div>;
}

^(the code is stripped down to only contain the necessary stuff)

This will throw an TypeError: Cannot read property 'id' of null .

It took me a long time to realize that those two setState calls aren't batched together, instead it will render the component right after setStatus("success"); and before calling setData(data); in the very next line, thus data is still null!

This isn't the first time I called setState somewhere that wasn't a event handler: I have done fetching data several times before, but I must have always done something unintentionally to prevent this:

• calling them in the right order by coincidence
• checking implicitly if the value exists in my JSX (e.g. via nullish coalescing (??) or optional chaining (?.))
• by having an initialState that's still will render without throwing (e.g. mapping over something that's initialState is an empty array)
• using useReducer instead of two useState, because those two values are interconnected (which is the right solution, imho)

I'm obviously not the first one who found this out, but I hope that I could find at least one person who wasn't aware of this and can keep him from falling into the same trap as me!

Here are some interesting links I found on this topic:

• Does React batch state update functions when using hooks? - Stack Overflow
• [Question] Keep to single setState call? · Issue #10231 · facebook/react:
  • "*This is implementation detail and may change in futur

Hi,

I would like to collect over time how many time our nodes got terminated by the "node-termination-handler" where can I find that info, the built-in /metric endpoint does not hold it as it terminated when the node goes down, maybe CloudWatch...? Kubernetes events?

Thanks in advanced .

Hi,

I am making a replacement pack and I want to remove the NVG's from certain classes without overriding the linkedItems Array, the only way i can think of is running a init script and call unassign and remove item on NVGs;

but that does not work at all:

class EventHandlers {

init = "this unassignItem 'NVGoggles_INDEP';";};