Can't Change Text of ActionMenuItemView with RxKotlin

Question

I'm trying to write an Android app with Kotlin. Now, I want to show a counter in the ActionBar. I added an item called show_timer for that. Each second, it should count up by one:

override fun onWindowFocusChanged(hasFocus: Boolean) {
    val item = findViewById(R.id.show_timer) as ActionMenuItemView
    PublishSubject.interval(1, java.util.concurrent.TimeUnit.SECONDS, Schedulers.newThread())
            .subscribeBy(onNext = {item.text = it.toString()})

    super.onWindowFocusChanged(hasFocus)
}

But somehow this doesn't work. It updates the default text to 0, but after that it does nothing. Does someone know why this doesn't work?

Thank you in advance,

Niklas

Don't you need to `.observeOn(AndroidSchedulers.mainThread())`? — tim_yates, Mar 13 '17 at 20:12
Yup, that's it. You should post that as the answer. Odd that it doesn't crash or anything though. — zsmb13, Mar 13 '17 at 20:17

score 0 · Accepted Answer · answered Mar 13 '17 at 22:30

0

In order for the text to update, it needs to be updated on the main thread (not the Schedulers.newThread() one)

Adding:

.observeOn(AndroidSchedulers.mainThread())

Should fix things, and get the label to update

answered Mar 13 '17 at 22:30

tim_yates

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Thank you, this works :). However, could you explain why it still updated the text once in my example? – Niklas Wünsche Mar 14 '17 at 10:11

Can't Change Text of ActionMenuItemView with RxKotlin

1 Answers1