Hi guys How can I use `BackHandler` in the project I am trying to use customise back handler in my project I am trying to follow this <https stackoverflow com a 69151539 8266651|answer> but it didn t work to go back in screen

@Composable
fun TopBar(
    activity: ComponentActivity = (LocalContext.current as ComponentActivity),
    handleOnBackPressed: () -> Unit = { activity.finish() },
    content: @Composable (PaddingValues) -> Unit = {}
) {
    var isBackPressed by remember { mutableStateOf(false) }
    Scaffold(
        topBar = {
            TopAppBar(
                title = {},
                navigationIcon = {
                    IconButton(
                        onClick = { isBackPressed = true }
                    ) {
                        Icon(
                            imageVector = Icons.Filled.ArrowBack,
                            contentDescription = null,
                            tint = Aqua
                        )
                    }
                    if (isBackPressed) {
                        BackHandler(enabled = true, onBack = {
                            handleOnBackPressed()
                        })
                    }
                }
            )
        },
        content = content
    )
}

I am running this in Pixel 7 with Android 13. Using

compose_bom = "2022.11.00"

. Thanks

Zaki Shaikh

02/10/2023, 4:11 PM

What do you want to achieve by this actually

KotlinLeaner

02/10/2023, 4:12 PM

I want to normal close the activity.

activity.onBackPressed()

is deprecated.

Zaki Shaikh

02/10/2023, 4:15 PM

Simply call activity.finish() in onclick of navigation icon

KotlinLeaner

02/10/2023, 4:20 PM

It works, but what is the d/w

finish

and

BackHandler

Zaki Shaikh

02/10/2023, 4:31 PM

BackHandler when user presses back button and you don't want to go back and you need to do some task. E.g when drawer is open so you pass condition in BackHandler argument that if deawer is opened then close it first and then in second press of back it goes back.

KotlinLeaner

02/10/2023, 4:33 PM

How can we do that, I have some condition like that..

Zaki Shaikh

02/10/2023, 4:39 PM

I will share code

KotlinLeaner

02/10/2023, 4:40 PM

Thanks

Zaki Shaikh

02/11/2023, 5:02 AM

Copy code

var state by remember { mutableStateOf("") }
    var textFocus by remember { mutableStateOf(false) }
    val focusManager = LocalFocusManager.current
    BackHandler(textFocus) { focusManager.clearFocus() }
    
    OutlinedTextField(
        value = state,
        onValueChange = { str -> state = str },
        modifier = Modifier.onFocusChanged { focusState -> textFocus = focusState.hasFocus }
    )

in this code when textField has focus, so when user presses the back button it will first clearFcous in BackHandler lambda then in second press of back button it goes back.

7 Views