WindowInfoRepo.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
import android.app.Activity
import android.content.Context
import androidx.annotation.RestrictTo
import androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP
import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.flow.Flow
/**
* An interface to provide all the relevant info about a [android.view.Window].
*/
public interface WindowInfoRepo {
/**
* Returns the [WindowMetrics] according to the current system state.
*
*
* The metrics describe the size of the area the window would occupy with
* [MATCH_PARENT][android.view.WindowManager.LayoutParams.MATCH_PARENT] width and height
* and any combination of flags that would allow the window to extend behind display cutouts.
*
*
* The value of this is based on the **current** windowing state of the system. For
* example, for activities in multi-window mode, the metrics returned are based on the
* current bounds that the user has selected for the [Activity][android.app.Activity]'s
* window.
*
* @see maximumWindowMetrics
* @see android.view.WindowManager.getCurrentWindowMetrics
*/
public val currentWindowMetrics: WindowMetrics
/**
* Returns the largest [WindowMetrics] an app may expect in the current system state.
*
*
* The metrics describe the size of the largest potential area the window might occupy with
* [MATCH_PARENT][android.view.WindowManager.LayoutParams.MATCH_PARENT] width and height
* and any combination of flags that would allow the window to extend behind display cutouts.
*
*
* The value of this is based on the largest **potential** windowing state of the system.
* For example, for activities in multi-window mode the metrics returned are based on what the
* bounds would be if the user expanded the window to cover the entire screen.
*
*
* Note that this might still be smaller than the size of the physical display if certain
* areas of the display are not available to windows created for the associated [Context].
* For example, devices with foldable displays that wrap around the enclosure may split the
* physical display into different regions, one for the front and one for the back, each acting
* as different logical displays. In this case [maximumWindowMetrics] would return
* the region describing the side of the device the associated [context's][Context]
* window is placed.
*
* @see currentWindowMetrics
* @see android.view.WindowManager.getMaximumWindowMetrics
*/
public val maximumWindowMetrics: WindowMetrics
/**
* A [Flow] of [WindowLayoutInfo] that contains all the available features.
*/
public val windowLayoutInfo: Flow<WindowLayoutInfo>
public companion object {
private var decorator: WindowInfoRepoDecorator = EmptyDecorator
@JvmStatic
@ExperimentalCoroutinesApi
public fun create(activity: Activity): WindowInfoRepo {
val taggedRepo = activity.getTag(R.id.androidx_window_activity_scope) as? WindowInfoRepo
val repo = taggedRepo ?: activity.getOrCreateTag(R.id.androidx_window_activity_scope) {
WindowInfoRepoImp(
activity,
WindowBoundsHelper(),
ExtensionWindowBackend.getInstance(activity)
)
}
return decorator.decorate(repo)
}
@JvmStatic
@RestrictTo(LIBRARY_GROUP)
public fun overrideDecorator(overridingDecorator: WindowInfoRepoDecorator) {
decorator = overridingDecorator
}
@JvmStatic
@RestrictTo(LIBRARY_GROUP)
public fun reset() {
decorator = EmptyDecorator
}
}
}
@RestrictTo(LIBRARY_GROUP)
public interface WindowInfoRepoDecorator {
/**
* Returns an instance of [WindowInfoRepo] associated to the [Activity]
*/
@RestrictTo(LIBRARY_GROUP)
public fun decorate(repo: WindowInfoRepo): WindowInfoRepo
}
private object EmptyDecorator : WindowInfoRepoDecorator {
override fun decorate(repo: WindowInfoRepo): WindowInfoRepo {
return repo
}
}