WindowBackend.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.window.layout

import android.app.Activity
import androidx.core.util.Consumer
import java.util.concurrent.Executor

/**
 * Backing interface for [WindowInfoTracker] instances that serve as the default
 * information supplier.
 */
internal interface WindowBackend {
    /**
     * Registers a callback for layout changes of the window for the supplied [Activity].
     * Must be called only after the it is attached to the window.
     */
    fun registerLayoutChangeCallback(
        activity: Activity,
        executor: Executor,
        callback: Consumer<WindowLayoutInfo>
    )

    /**
     * Unregisters a callback for window layout changes of the [Activity] window.
     */
    fun unregisterLayoutChangeCallback(callback: Consumer<WindowLayoutInfo>)
}