Coroutine only the original thread that created a view hierarchy can touch its views.

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posted at 2021-07-16

updated at 2021-07-16

ネットで探してもわかりやすいのが見つからなかったのでざっくりまとめ

出会ったエラー

コルーチンを使おうとしたらエラー
suspend function 'mySuspendFunction' should be called only from a coroutine or another suspend function
訳：susupend付きの関数はコルーチン、もしくはほかのsuspend付きの関数から呼ぶべし

コルーチンの中でUIを更新したらエラー
Only the original thread that created a view hierarchy can touch its views.
訳：Viewをいじるのは大元のスレッドでやってくんね？

こんな感じで回避

private fun functionCaller(){ // コルーチンの開始はこれ GlobalScope.launch { mySuspendFunction() } } private suspend fun mySuspendFunction() = withContext(Dispatchers.IO) { /* コルーチンを使いたくなる長い処理 */ // UIの更新はUIスレッドで行う必要がある。 runOnUiThread { myUiText.text = valueMadeInThisFunction } }

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Only the original thread that created a view hierarchy can touch its views

In this tutorial, we shall learn to fix Android Exception CalledFromWrongThreadException : Only the original thread that created a view hierarchy can touch its views. You might have come across this error while from a thread you are trying to set some property of a View or extract some property of a View, that belong to UI thread.

Only the original thread that created a view hierarchy can, This "Only the original thread that created a view hierarchy can touch its views" error given after react native version upgrade 44.2 to 47.2.

CalledFromWrongThreadException Only the original thread that created a view

Look like you are on the wrong thread. Try using a Handler to update the GUI on the right thread. See Handling Expensive Operations in the UI Thread example from android.com. Basically you would wrap byeSetup in a Runnable and invoke it with a Handler instance.

It's fairly common practice that you can only modify UI elements from the UI thread. Also, XF is not a phone OS in itself but rather just a tool that makes it easier to develop cross-platform apps (a distinction that seems to be forgotten quite a bit on this forum).

Only the original thread that created a view hierarchy can touch its views react-native

It says whichever thread created a view, only that can touch its views. It is because the created view is inside that thread’s space. The view creation (GUI) happens in UI (Main) thread. So, you always use UI thread to access those methods.

React native only the original thread that created a view hierarchy can touch its views Only the original thread that created a view hierarchy can, This "Only the original thread that created a view hierarchy can touch its views" error given after react native version upgrade 44.2 to 47.2.

Android only the original thread that created a view hierarchy can touch

Fix Android CalledFromWrongThreadException. In this tutorial, we shall learn to fix Android Exception CalledFromWrongThreadException : Only the original thread that created a view hierarchy can touch its views.

Only the original thread that created a view hierarchy can touch its views.

Exception: Only the original thread that created a view hierarchy can , Exception: Only the original thread that created a view hierarchy can touch its views It's fairly common practice that you can only modify UI elements from a label in the view and do other functions with xamarin c#code] :). 0.

Kotlin CalledFromWrongThreadException

Kotlin run on main thread Running code in main thread from another thread, Kotlin versions. When you are on an activity, then use runOnUiThread { //code that runs in main }. If you try to touch view of UI thread from another thread, you will get Android CalledFromWrongThreadException.

get Android CalledFromWrongThreadException. Following is an example Android Application demonstrating the usage of runOnUiThread() method. Create Android Application with Kotlin Support with following details and rest values to default.

In the example above login function is a suspend function which will crash if you execute it from coroutine which uses non- Main dispatcher. CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views. ✅ Design your suspend function in a way that it can be executed from any coroutine dispatcher.

If you try to touch view of UI thread from another thread, you will get Android CalledFromWrongThreadException. Following is an example Android Application demonstrating the usage of runOnUiThread() method. Create Android Application with Kotlin Support with following details and rest values to default.

If you try to touch view of UI thread from another thread, you will get Android CalledFromWrongThreadException. Following is an example Android Application demonstrating the usage of runOnUiThread () method. Create Android Application with Kotlin Support with following details and rest values to default.

Kotlin has great support and many contributors in its fast-growing global community. Enjoy the benefits of a rich ecosystem with a wide range of community libraries. Help is never far away – consult extensive community resources or ask the Kotlin team directly.

Erroronly the original thread that created a view hierarchy can touch its views

This is explicitly throwing an error. It says whichever thread created a view, only that can touch its views. It is because the created view is inside that thread’s space. The view creation (GUI) happens in UI (Main) thread.

Otherwise consider posting your into or clear calls to the main thread using a Handler instead

FATAL EXCEPTION: main Process: com.myproject.android.customer.debug, PID: 25205 java.lang.IllegalStateException: You can't start or clear loads in RequestListener or Target callbacks. If you must do so, consider posting your into() or clear() calls to the main thread using a Handler instead.

A Handler is a component that can be attached to a thread and then made to perform some action on that thread via simple messages or Runnable tasks. It works in conjunction with another component, Looper, which is in charge of message processing in a particular thread.

* process is created for your application, its main thread is dedicated to * running a message queue that takes care of managing the top-level * application objects (activities, broadcast receivers, etc) and any windows * they create. You can create your own threads, and communicate back with * the main application thread through a Handler.

You can rewrite the program using only one try-catch block. An runtime exception is thrown and caught. An instance of ________ describes the errors caused by your program and external circumstances.

If you do not intend to upload binary content, consider instead using the FormData API. Note: The non-standard sendAsBinary method is considered deprecated as of Gecko 31 (Firefox 31 / Thunderbird 31 / SeaMonkey 2.28) and will be removed soon.

Do your homework before posting: If it is clear that you have done basic background research and searched already for the answer, you are far more likely to get an informative response. Search the ns-3-users group. The web interface has a nice search feature, use it. Search the web. Use your preferred search engine, you may find good tips.

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How do you fix only the original thread that created a view hierarchy can touch its views?

To fix this error, wrap the code that has to be executed on UI thread in a Runnable instance passed to runOnUiThread() method.

Does coroutine run on main thread?

On Android, coroutines help to manage long-running tasks that might otherwise block the main thread and cause your app to become unresponsive.

Does coroutine create new thread?

The launch function is a coroutine builder that starts a new coroutine without blocking the current thread and returns a reference to the coroutine as a Job object: runBlocking { val job = launch(Dispatchers.

What is a benefit of using coroutines over threads?

While doing things on your own managing thread pools manually is possible, coroutines is the recommended solution for asynchronous programming on Android due to the built-in cancellation support, easier error handling, structured concurrency which reduces the likelihood of memory leaks, and its integration with Jetpack ...