CODEWITHSUNDEEP
androidkotlinandroid-jetpack-compose
Lingli Li
Lingli Li

Reputation: 153

onKeyEvent Modifier doesn't work in Jetpack Compose

return ComposeView(requireContext()).apply {
    setContent {
        Box(
            Modifier
                .onKeyEvent {
                    if (it.isCtrlPressed && it.key == Key.A) {
                        println("Ctrl + A is pressed")
                        true
                    } else {
                        false
                    }
                }
                .focusable()
        )
    }
}

Why the key event cannot be called in fragment while using hardware keyboard of tablet?

Upvotes: 15

Views: 7755

Answers (2)

JJD
JJD

Reputation: 51824

If you are using androidx.compose.material3.OutlinedTextField then you can use KeyboardActions instead:

keyboardActions = KeyboardActions(onDone = { /* Do something */ })

Upvotes: 0

Phil Dukhov
Phil Dukhov

Reputation: 87824

As documentation of onKeyEvent says:

will allow it to intercept hardware key events when it (or one of its children) is focused.

Which means you need to make your box focused, not just focusable. To do this you need a FocusRequester, in my example I'm asking focus when view renders. Check out more in this article

For the future note, that if user taps on a text field, your box will loose focus, but onKeyEvent still gonna work if this txt field is inside the box

Looks like empty box cannot become focused, so you need to add some size with a modifier. It still will be invisible:

val requester = remember { FocusRequester() }
Box(
    Modifier
        .onKeyEvent {
            if (it.isCtrlPressed && it.key == Key.A) {
                println("Ctrl + A is pressed")
                true
            } else {
                false
            }
        }
        .focusRequester(requester)
        .focusable()
        .size(10.dp)
)
LaunchedEffect(Unit) {
    requester.requestFocus()
}

Alternatively just add content to Box so it will stretch and .size modifier won't be needed anymore

This code works fine with my Bluetooth keyboard + android smartphone, emulator seems not recognizing CTRL

Upvotes: 18

Related Questions