android - Kotlin 协程 CalledFromWrongThreadException

Question

我正在尝试使用 Kotlin 协程在后台运行一些繁重的工作。

但是我收到了这个错误信息，

'android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.'

fun setList() {
    media_image_list.adapter = imageListAdapter
    ...

    launch {
        val images = getImages(galleryPath)
        imageListAdapter.setItems(images)
    }
}




suspend private fun getImages(): MutableList<Image> {
    val uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
    ...
}

如何让它在后台正确运行？

Answer 1

我建议通过以下方式解决它:

首先，使用 withContext 函数将您的“繁重工作”显式卸载到后台线程中，如下所示:

// explicitly request it to be executed in bg thread
suspend private fun getImages(): MutableList<Image> = withContext(CommonPool) {
    val uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
    ...
}

然后，始终在 UI 线程中运行接触 View 或其他 UI 对象的协程:

launch(UI) {
    val images = getImages(galleryPath)
    imageListAdapter.setItems(images)
}