AndroidWindowSizeClass.android.kt
/*
* Copyright 2022 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.compose.material3.windowsizeclass
import android.app.Activity
import androidx.compose.runtime.Composable
import androidx.compose.ui.graphics.toComposeRect
import androidx.compose.ui.platform.LocalConfiguration
import androidx.compose.ui.platform.LocalDensity
import androidx.window.layout.WindowMetricsCalculator
/**
* Calculates the window's [WindowSizeClass] for the provided [activity].
*
* A new [WindowSizeClass] will be returned whenever a configuration change causes the width or
* height of the window to cross a breakpoint, such as when the device is rotated or the window
* is resized.
*
* @sample androidx.compose.material3.windowsizeclass.samples.AndroidWindowSizeClassSample
*/
@ExperimentalMaterial3WindowSizeClassApi
@Composable
fun calculateWindowSizeClass(activity: Activity): WindowSizeClass {
// Observe view configuration changes and recalculate the size class on each change. We can't
// use Activity#onConfigurationChanged as this will sometimes fail to be called on different
// API levels, hence why this function needs to be @Composable so we can observe the
// ComposeView's configuration changes.
LocalConfiguration.current
val density = LocalDensity.current
val metrics = WindowMetricsCalculator.getOrCreate().computeCurrentWindowMetrics(activity)
val size = with(density) { metrics.bounds.toComposeRect().size.toDpSize() }
return WindowSizeClass.calculateFromSize(size)
}