在 Android 33 及更高版本中按后退不会关闭底部工作表

Question

我遇到了 Jetpack Compose 的问题，即在运行 Android 33 及更高版本的设备上，后按事件不会关闭底部工作表。有没有办法覆盖此行为或在 Jetpack Compose 中实现后按事件的自定义处理？我正在寻找解决这个特定问题的见解或解决方案。

为了了解更多上下文，我的项目使用导航组件进行导航。底部工作表在没有它的项目中工作得很好。

我尝试使用 Backhandler 来处理后压。

BackHandler {
    coroutineScope.launch {
        if (bottomSheetScaffoldState.isVisible) {
            showBottomSheet = false
            bottomSheetScaffoldState.hide()
        } else {
            showBottomSheet = true
            bottomSheetScaffoldState.show()
        }
    }
}

这是我的底页

ModalBottomSheet(
    onDismissRequest = { showBottomSheet = false },
    shape = RoundedCornerShape(
        topEnd = Constants.BOTTOM_SHEET_CORNER_RADIUS,
        topStart = Constants.BOTTOM_SHEET_CORNER_RADIUS
    ),
    sheetState = bottomSheetScaffoldState,
    windowInsets = WindowInsets(0, 0, 0, 8),
) {
    BoxWithConstraints(
        Modifier
            .navigationBarsPadding()
            .padding(bottom = 10.dp)
    ) {
        Column(
            modifier = Modifier
                .fillMaxWidth()
                .padding(bottom = 10.dp)
                .navigationBarsPadding()
        ) {
            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .clickable {
                      
                    }
                    .height(44.dp),
                verticalAlignment = Alignment.CenterVertically,
            ) {
                Text(
                    text = "Discard Changes",
                    style = MaterialTheme.typography.bodyLarge,
                    fontWeight = FontWeight.Normal,
                    fontSize = 15.sp,
                    color = colorResource(
                        id = R.color.system_red
                    ),
                    textAlign = TextAlign.Start,
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(horizontal = 16.dp)
                )
            }
            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .clickable {
                        coroutineScope
                            .launch {
                                bottomSheetScaffoldState.hide()
                            }
                            .invokeOnCompletion {
                                if (!bottomSheetScaffoldState.isVisible) {
                                    showBottomSheet = false
                                    keyboard?.show()
                                }
                            }
                    }
                    .height(44.dp),
                verticalAlignment = Alignment.CenterVertically,
            ) {
                Text(
                    text = "Keep Editing",
                    style = MaterialTheme.typography.bodyLarge,
                    fontWeight = FontWeight.Normal,
                    fontSize = 15.sp,
                    color = if (!isSystemInDarkTheme()) colorResource(id = R.color.black) else colorResource(
                        id = R.color.white
                    ),
                    textAlign = TextAlign.Start,
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(horizontal = 16.dp)
                )
            }
        }
    }
}

此解决方案适用于 Android 12 及更低版本的设备，但不适用于 API 33 及更高版本的设备。

Answer 1

onBackPressed 在 API 33 中已被弃用，以上版本使用 getOnBackInvokedDispatcher 代替。 https://developer.android.com/guide/navigation/custom-back/predictive-back-gesture#kotlin

 if (BuildCompat.isAtLeastT()) {
    onBackInvokedDispatcher.registerOnBackInvokedCallback(
        OnBackInvokedDispatcher.PRIORITY_DEFAULT
    ) {
        /**
         * onBackPressed logic goes here. For instance:
         * Prevents closing the app to go home screen when in the
         * middle of entering data to a form
         * or from accidentally leaving a fragment with a WebView in it
         *
         * Unregistering the callback to stop intercepting the back gesture:
         * When the user transitions to the topmost screen (activity, fragment)
         * in the BackStack, unregister the callback by using
         * OnBackInvokeDispatcher.unregisterOnBackInvokedCallback
         * (https://developer.android.com/reference/kotlin/android/window/OnBackInvokedDispatcher#unregisteronbackinvokedcallback)
         */
    }
}