How can I delay a loading spinner and start it conditionally inside of a coroutine?

Question

I currently have a way that works, but it uses a boolean that is external to the coroutine, and it just feels like there must be a more elegant way to do it. I plan on using this pattern in many places in my app so I want it to be "right". Currently I solve the problem like this:

private loadingFinished: Boolean = false
private fun loadData() {
    showLoading.value = false
    loadingFinished = false
    viewModelScope.launch {
        delay(500)
        if (!loadingFinished)
            showLoading.value = true
    }
    viewModelScope.launch {
        try {
            data = api.thisIsASuspendFunction
            updateUI.call()
            loadingFinished = true
            showLoading.value = false
        }
        catch (e: Exception){
            loadingFinished = true
            showLoading.value = false
            showError.value = errorHelper.getErrorMessageType(e)
        }
    }
}

This works exactly as I expect it to right now: If the api call takes longer than half a second, the progress spinner shows and is stopped once the suspend function finishes. But is there a more correct way to accomplish this?

Answer 1

You can use job cancellation for it:

private fun loadData() {
    showLoading.value = false
    viewModelScope.launch {
        val loadingJob = launch {
            delay(500)
            showLoading.value = true
        }
        try {
            data = api.thisIsASuspendFunction
            loadingJob.cancel()
            updateUI.call()
            showLoading.value = false
        }
        catch (e: Exception){
            loadingJob.cancel()
            showLoading.value = false
            showError.value = errorHelper.getErrorMessageType(e)
        }
    }
}