ActionBarOnDestinationChangedListener.kt
/*
* Copyright 2018 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.navigation.ui
import android.graphics.drawable.Drawable
import androidx.annotation.RestrictTo
import androidx.annotation.StringRes
import androidx.appcompat.app.AppCompatActivity
/**
* The OnDestinationChangedListener specifically for keeping the ActionBar updated.
* This handles both updating the title and updating the Up Indicator, transitioning between
* the drawer icon and up arrow as needed.
* @hide
*/
@RestrictTo(RestrictTo.Scope.LIBRARY)
internal class ActionBarOnDestinationChangedListener(
private val activity: AppCompatActivity,
configuration: AppBarConfiguration
) : AbstractAppBarOnDestinationChangedListener(
activity.drawerToggleDelegate!!.actionBarThemedContext,
configuration
) {
override fun setTitle(title: CharSequence?) {
val actionBar = activity.supportActionBar
require(actionBar != null) {
"Activity $activity does not have an ActionBar set via setSupportActionBar()"
}
actionBar.setTitle(title)
}
override fun setNavigationIcon(icon: Drawable?, @StringRes contentDescription: Int) {
val actionBar = activity.supportActionBar
require(actionBar != null) {
"Activity $activity does not have an ActionBar set via setSupportActionBar()"
}
actionBar.setDisplayHomeAsUpEnabled(true)
val delegate = activity.drawerToggleDelegate
require(delegate != null) {
"Activity $activity does not have an DrawerToggleDelegate set"
}
delegate.setActionBarUpIndicator(icon, contentDescription)
}
}