SwipeDismissableNavHostController.kt

/*
 * Copyright 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.wear.compose.navigation

import androidx.compose.runtime.collectAsState
import androidx.compose.runtime.Composable
import androidx.compose.runtime.remember
import androidx.compose.runtime.State
import androidx.navigation.NavBackStackEntry
import androidx.navigation.NavController
import androidx.navigation.NavHostController
import androidx.navigation.compose.rememberNavController

/**
 * Creates a NavHostController that handles the adding of the [WearNavigator]
 * from androidx.wear.compose.navigation.
 */
@Composable
public fun rememberSwipeDismissableNavController(): NavHostController {
    return rememberNavController(remember { WearNavigator() })
}

/**
 * Gets the current navigation back stack entry as a [State]. When the given navController
 * changes the back stack due to a [NavController.navigate] or [NavController.popBackStack] this
 * will trigger a recompose and return the top entry on the back stack.
 *
 * @return state of the current back stack entry
 */
@Composable
public fun NavController.currentBackStackEntryAsState(): State<NavBackStackEntry?> {
    return currentBackStackEntryFlow.collectAsState(null)
}