packages/SystemUI/compose/core/src/com/android/compose/SystemUiController.kt - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 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 com.android.compose

 import android.app.Activity
 import android.content.Context
 import android.content.ContextWrapper
 import android.os.Build
 import android.view.View
 import android.view.Window
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.Stable
 import androidx.compose.runtime.remember
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.compositeOver
 import androidx.compose.ui.graphics.luminance
 import androidx.compose.ui.graphics.toArgb
 import androidx.compose.ui.platform.LocalView
 import androidx.compose.ui.window.DialogWindowProvider
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowCompat
 import androidx.core.view.WindowInsetsCompat

 /**
  * *************************************************************************************************
  * This file was forked from
  * https://github.com/google/accompanist/blob/main/systemuicontroller/src/main/java/com/google/accompanist/systemuicontroller/SystemUiController.kt
  * and will be removed once it lands in AndroidX.
  */

 /**
  * A class which provides easy-to-use utilities for updating the System UI bar colors within Jetpack
  * Compose.
  *
  * @sample com.google.accompanist.sample.systemuicontroller.SystemUiControllerSample
  */
 @Stable
 interface SystemUiController {

     /**
      * Property which holds the status bar visibility. If set to true, show the status bar,
      * otherwise hide the status bar.
      */
     var isStatusBarVisible: Boolean

     /**
      * Property which holds the navigation bar visibility. If set to true, show the navigation bar,
      * otherwise hide the navigation bar.
      */
     var isNavigationBarVisible: Boolean

     /**
      * Property which holds the status & navigation bar visibility. If set to true, show both bars,
      * otherwise hide both bars.
      */
     var isSystemBarsVisible: Boolean
         get() = isNavigationBarVisible && isStatusBarVisible
         set(value) {
             isStatusBarVisible = value
             isNavigationBarVisible = value
         }

     /**
      * Set the status bar color.
      *
      * @param color The **desired** [Color] to set. This may require modification if running on an
      *   API level that only supports white status bar icons.
      * @param darkIcons Whether dark status bar icons would be preferable.
      * @param transformColorForLightContent A lambda which will be invoked to transform [color] if
      *   dark icons were requested but are not available. Defaults to applying a black scrim.
      * @see statusBarDarkContentEnabled
      */
     fun setStatusBarColor(
         color: Color,
         darkIcons: Boolean = color.luminance() > 0.5f,
         transformColorForLightContent: (Color) -> Color = BlackScrimmed
     )

     /**
      * Set the navigation bar color.
      *
      * @param color The **desired** [Color] to set. This may require modification if running on an
      *   API level that only supports white navigation bar icons. Additionally this will be ignored
      *   and [Color.Transparent] will be used on API 29+ where gesture navigation is preferred or
      *   the system UI automatically applies background protection in other navigation modes.
      * @param darkIcons Whether dark navigation bar icons would be preferable.
      * @param navigationBarContrastEnforced Whether the system should ensure that the navigation bar
      *   has enough contrast when a fully transparent background is requested. Only supported on API
      *   29+.
      * @param transformColorForLightContent A lambda which will be invoked to transform [color] if
      *   dark icons were requested but are not available. Defaults to applying a black scrim.
      * @see navigationBarDarkContentEnabled
      * @see navigationBarContrastEnforced
      */
     fun setNavigationBarColor(
         color: Color,
         darkIcons: Boolean = color.luminance() > 0.5f,
         navigationBarContrastEnforced: Boolean = true,
         transformColorForLightContent: (Color) -> Color = BlackScrimmed
     )

     /**
      * Set the status and navigation bars to [color].
      *
      * @see setStatusBarColor
      * @see setNavigationBarColor
      */
     fun setSystemBarsColor(
         color: Color,
         darkIcons: Boolean = color.luminance() > 0.5f,
         isNavigationBarContrastEnforced: Boolean = true,
         transformColorForLightContent: (Color) -> Color = BlackScrimmed
     ) {
         setStatusBarColor(color, darkIcons, transformColorForLightContent)
         setNavigationBarColor(
             color,
             darkIcons,
             isNavigationBarContrastEnforced,
             transformColorForLightContent
         )
     }

     /** Property which holds whether the status bar icons + content are 'dark' or not. */
     var statusBarDarkContentEnabled: Boolean

     /** Property which holds whether the navigation bar icons + content are 'dark' or not. */
     var navigationBarDarkContentEnabled: Boolean

     /**
      * Property which holds whether the status & navigation bar icons + content are 'dark' or not.
      */
     var systemBarsDarkContentEnabled: Boolean
         get() = statusBarDarkContentEnabled && navigationBarDarkContentEnabled
         set(value) {
             statusBarDarkContentEnabled = value
             navigationBarDarkContentEnabled = value
         }

     /**
      * Property which holds whether the system is ensuring that the navigation bar has enough
      * contrast when a fully transparent background is requested. Only has an affect when running on
      * Android API 29+ devices.
      */
     var isNavigationBarContrastEnforced: Boolean
 }

 /**
  * Remembers a [SystemUiController] for the given [window].
  *
  * If no [window] is provided, an attempt to find the correct [Window] is made.
  *
  * First, if the [LocalView]'s parent is a [DialogWindowProvider], then that dialog's [Window] will
  * be used.
  *
  * Second, we attempt to find [Window] for the [Activity] containing the [LocalView].
  *
  * If none of these are found (such as may happen in a preview), then the functionality of the
  * returned [SystemUiController] will be degraded, but won't throw an exception.
  */
 @Composable
 fun rememberSystemUiController(
     window: Window? = findWindow(),
 ): SystemUiController {
     val view = LocalView.current
     return remember(view, window) { AndroidSystemUiController(view, window) }
 }

 @Composable
 private fun findWindow(): Window? =
     (LocalView.current.parent as? DialogWindowProvider)?.window
         ?: LocalView.current.context.findWindow()

 private tailrec fun Context.findWindow(): Window? =
     when (this) {
         is Activity -> window
         is ContextWrapper -> baseContext.findWindow()
         else -> null
     }

 /**
  * A helper class for setting the navigation and status bar colors for a [View], gracefully
  * degrading behavior based upon API level.
  *
  * Typically you would use [rememberSystemUiController] to remember an instance of this.
  */
 internal class AndroidSystemUiController(private val view: View, private val window: Window?) :
     SystemUiController {
     private val windowInsetsController = window?.let { WindowCompat.getInsetsController(it, view) }

     override fun setStatusBarColor(
         color: Color,
         darkIcons: Boolean,
         transformColorForLightContent: (Color) -> Color
     ) {
         statusBarDarkContentEnabled = darkIcons

         window?.statusBarColor =
             when {
                 darkIcons && windowInsetsController?.isAppearanceLightStatusBars != true -> {
                     // If we're set to use dark icons, but our windowInsetsController call didn't
                     // succeed (usually due to API level), we instead transform the color to
                     // maintain contrast
                     transformColorForLightContent(color)
                 }
                 else -> color
             }.toArgb()
     }

     override fun setNavigationBarColor(
         color: Color,
         darkIcons: Boolean,
         navigationBarContrastEnforced: Boolean,
         transformColorForLightContent: (Color) -> Color
     ) {
         navigationBarDarkContentEnabled = darkIcons
         isNavigationBarContrastEnforced = navigationBarContrastEnforced

         window?.navigationBarColor =
             when {
                 darkIcons && windowInsetsController?.isAppearanceLightNavigationBars != true -> {
                     // If we're set to use dark icons, but our windowInsetsController call didn't
                     // succeed (usually due to API level), we instead transform the color to
                     // maintain contrast
                     transformColorForLightContent(color)
                 }
                 else -> color
             }.toArgb()
     }

     override var isStatusBarVisible: Boolean
         get() {
             return ViewCompat.getRootWindowInsets(view)
                 ?.isVisible(WindowInsetsCompat.Type.statusBars()) == true
         }
         set(value) {
             if (value) {
                 windowInsetsController?.show(WindowInsetsCompat.Type.statusBars())
             } else {
                 windowInsetsController?.hide(WindowInsetsCompat.Type.statusBars())
             }
         }

     override var isNavigationBarVisible: Boolean
         get() {
             return ViewCompat.getRootWindowInsets(view)
                 ?.isVisible(WindowInsetsCompat.Type.navigationBars()) == true
         }
         set(value) {
             if (value) {
                 windowInsetsController?.show(WindowInsetsCompat.Type.navigationBars())
             } else {
                 windowInsetsController?.hide(WindowInsetsCompat.Type.navigationBars())
             }
         }

     override var statusBarDarkContentEnabled: Boolean
         get() = windowInsetsController?.isAppearanceLightStatusBars == true
         set(value) {
             windowInsetsController?.isAppearanceLightStatusBars = value
         }

     override var navigationBarDarkContentEnabled: Boolean
         get() = windowInsetsController?.isAppearanceLightNavigationBars == true
         set(value) {
             windowInsetsController?.isAppearanceLightNavigationBars = value
         }

     override var isNavigationBarContrastEnforced: Boolean
         get() = Build.VERSION.SDK_INT >= 29 && window?.isNavigationBarContrastEnforced == true
         set(value) {
             if (Build.VERSION.SDK_INT >= 29) {
                 window?.isNavigationBarContrastEnforced = value
             }
         }
 }

 private val BlackScrim = Color(0f, 0f, 0f, 0.3f) // 30% opaque black
 private val BlackScrimmed: (Color) -> Color = { original -> BlackScrim.compositeOver(original) }
	/*
	* Copyright (C) 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 com.android.compose

	import android.app.Activity
	import android.content.Context
	import android.content.ContextWrapper
	import android.os.Build
	import android.view.View
	import android.view.Window
	import androidx.compose.runtime.Composable
	import androidx.compose.runtime.Stable
	import androidx.compose.runtime.remember
	import androidx.compose.ui.graphics.Color
	import androidx.compose.ui.graphics.compositeOver
	import androidx.compose.ui.graphics.luminance
	import androidx.compose.ui.graphics.toArgb
	import androidx.compose.ui.platform.LocalView
	import androidx.compose.ui.window.DialogWindowProvider
	import androidx.core.view.ViewCompat
	import androidx.core.view.WindowCompat
	import androidx.core.view.WindowInsetsCompat

	/**
	* *************************************************************************************************
	* This file was forked from
	* https://github.com/google/accompanist/blob/main/systemuicontroller/src/main/java/com/google/accompanist/systemuicontroller/SystemUiController.kt
	* and will be removed once it lands in AndroidX.
	*/

	/**
	* A class which provides easy-to-use utilities for updating the System UI bar colors within Jetpack
	* Compose.
	*
	* @sample com.google.accompanist.sample.systemuicontroller.SystemUiControllerSample
	*/
	@Stable
	interface SystemUiController {

	/**
	* Property which holds the status bar visibility. If set to true, show the status bar,
	* otherwise hide the status bar.
	*/
	var isStatusBarVisible: Boolean

	/**
	* Property which holds the navigation bar visibility. If set to true, show the navigation bar,
	* otherwise hide the navigation bar.
	*/
	var isNavigationBarVisible: Boolean

	/**
	* Property which holds the status & navigation bar visibility. If set to true, show both bars,
	* otherwise hide both bars.
	*/
	var isSystemBarsVisible: Boolean
	get() = isNavigationBarVisible && isStatusBarVisible
	set(value) {
	isStatusBarVisible = value
	isNavigationBarVisible = value
	}

	/**
	* Set the status bar color.
	*
	* @param color The desired [Color] to set. This may require modification if running on an
	* API level that only supports white status bar icons.
	* @param darkIcons Whether dark status bar icons would be preferable.
	* @param transformColorForLightContent A lambda which will be invoked to transform [color] if
	* dark icons were requested but are not available. Defaults to applying a black scrim.
	* @see statusBarDarkContentEnabled
	*/
	fun setStatusBarColor(
	color: Color,
	darkIcons: Boolean = color.luminance() > 0.5f,
	transformColorForLightContent: (Color) -> Color = BlackScrimmed
	)

	/**
	* Set the navigation bar color.
	*
	* @param color The desired [Color] to set. This may require modification if running on an
	* API level that only supports white navigation bar icons. Additionally this will be ignored
	* and [Color.Transparent] will be used on API 29+ where gesture navigation is preferred or
	* the system UI automatically applies background protection in other navigation modes.
	* @param darkIcons Whether dark navigation bar icons would be preferable.
	* @param navigationBarContrastEnforced Whether the system should ensure that the navigation bar
	* has enough contrast when a fully transparent background is requested. Only supported on API
	* 29+.
	* @param transformColorForLightContent A lambda which will be invoked to transform [color] if
	* dark icons were requested but are not available. Defaults to applying a black scrim.
	* @see navigationBarDarkContentEnabled
	* @see navigationBarContrastEnforced
	*/
	fun setNavigationBarColor(
	color: Color,
	darkIcons: Boolean = color.luminance() > 0.5f,
	navigationBarContrastEnforced: Boolean = true,
	transformColorForLightContent: (Color) -> Color = BlackScrimmed
	)

	/**
	* Set the status and navigation bars to [color].
	*
	* @see setStatusBarColor
	* @see setNavigationBarColor
	*/
	fun setSystemBarsColor(
	color: Color,
	darkIcons: Boolean = color.luminance() > 0.5f,
	isNavigationBarContrastEnforced: Boolean = true,
	transformColorForLightContent: (Color) -> Color = BlackScrimmed
	) {
	setStatusBarColor(color, darkIcons, transformColorForLightContent)
	setNavigationBarColor(
	color,
	darkIcons,
	isNavigationBarContrastEnforced,
	transformColorForLightContent
	)
	}

	/** Property which holds whether the status bar icons + content are 'dark' or not. */
	var statusBarDarkContentEnabled: Boolean

	/** Property which holds whether the navigation bar icons + content are 'dark' or not. */
	var navigationBarDarkContentEnabled: Boolean

	/**
	* Property which holds whether the status & navigation bar icons + content are 'dark' or not.
	*/
	var systemBarsDarkContentEnabled: Boolean
	get() = statusBarDarkContentEnabled && navigationBarDarkContentEnabled
	set(value) {
	statusBarDarkContentEnabled = value
	navigationBarDarkContentEnabled = value
	}

	/**
	* Property which holds whether the system is ensuring that the navigation bar has enough
	* contrast when a fully transparent background is requested. Only has an affect when running on
	* Android API 29+ devices.
	*/
	var isNavigationBarContrastEnforced: Boolean
	}

	/**
	* Remembers a [SystemUiController] for the given [window].
	*
	* If no [window] is provided, an attempt to find the correct [Window] is made.
	*
	* First, if the [LocalView]'s parent is a [DialogWindowProvider], then that dialog's [Window] will
	* be used.
	*
	* Second, we attempt to find [Window] for the [Activity] containing the [LocalView].
	*
	* If none of these are found (such as may happen in a preview), then the functionality of the
	* returned [SystemUiController] will be degraded, but won't throw an exception.
	*/
	@Composable
	fun rememberSystemUiController(
	window: Window? = findWindow(),
	): SystemUiController {
	val view = LocalView.current
	return remember(view, window) { AndroidSystemUiController(view, window) }
	}

	@Composable
	private fun findWindow(): Window? =
	(LocalView.current.parent as? DialogWindowProvider)?.window
	?: LocalView.current.context.findWindow()

	private tailrec fun Context.findWindow(): Window? =
	when (this) {
	is Activity -> window
	is ContextWrapper -> baseContext.findWindow()
	else -> null
	}

	/**
	* A helper class for setting the navigation and status bar colors for a [View], gracefully
	* degrading behavior based upon API level.
	*
	* Typically you would use [rememberSystemUiController] to remember an instance of this.
	*/
	internal class AndroidSystemUiController(private val view: View, private val window: Window?) :
	SystemUiController {
	private val windowInsetsController = window?.let { WindowCompat.getInsetsController(it, view) }

	override fun setStatusBarColor(
	color: Color,
	darkIcons: Boolean,
	transformColorForLightContent: (Color) -> Color
	) {
	statusBarDarkContentEnabled = darkIcons

	window?.statusBarColor =
	when {
	darkIcons && windowInsetsController?.isAppearanceLightStatusBars != true -> {
	// If we're set to use dark icons, but our windowInsetsController call didn't
	// succeed (usually due to API level), we instead transform the color to
	// maintain contrast
	transformColorForLightContent(color)
	}
	else -> color
	}.toArgb()
	}

	override fun setNavigationBarColor(
	color: Color,
	darkIcons: Boolean,
	navigationBarContrastEnforced: Boolean,
	transformColorForLightContent: (Color) -> Color
	) {
	navigationBarDarkContentEnabled = darkIcons
	isNavigationBarContrastEnforced = navigationBarContrastEnforced

	window?.navigationBarColor =
	when {
	darkIcons && windowInsetsController?.isAppearanceLightNavigationBars != true -> {
	// If we're set to use dark icons, but our windowInsetsController call didn't
	// succeed (usually due to API level), we instead transform the color to
	// maintain contrast
	transformColorForLightContent(color)
	}
	else -> color
	}.toArgb()
	}

	override var isStatusBarVisible: Boolean
	get() {
	return ViewCompat.getRootWindowInsets(view)
	?.isVisible(WindowInsetsCompat.Type.statusBars()) == true
	}
	set(value) {
	if (value) {
	windowInsetsController?.show(WindowInsetsCompat.Type.statusBars())
	} else {
	windowInsetsController?.hide(WindowInsetsCompat.Type.statusBars())
	}
	}

	override var isNavigationBarVisible: Boolean
	get() {
	return ViewCompat.getRootWindowInsets(view)
	?.isVisible(WindowInsetsCompat.Type.navigationBars()) == true
	}
	set(value) {
	if (value) {
	windowInsetsController?.show(WindowInsetsCompat.Type.navigationBars())
	} else {
	windowInsetsController?.hide(WindowInsetsCompat.Type.navigationBars())
	}
	}

	override var statusBarDarkContentEnabled: Boolean
	get() = windowInsetsController?.isAppearanceLightStatusBars == true
	set(value) {
	windowInsetsController?.isAppearanceLightStatusBars = value
	}

	override var navigationBarDarkContentEnabled: Boolean
	get() = windowInsetsController?.isAppearanceLightNavigationBars == true
	set(value) {
	windowInsetsController?.isAppearanceLightNavigationBars = value
	}

	override var isNavigationBarContrastEnforced: Boolean
	get() = Build.VERSION.SDK_INT >= 29 && window?.isNavigationBarContrastEnforced == true
	set(value) {
	if (Build.VERSION.SDK_INT >= 29) {
	window?.isNavigationBarContrastEnforced = value
	}
	}
	}

	private val BlackScrim = Color(0f, 0f, 0f, 0.3f) // 30% opaque black
	private val BlackScrimmed: (Color) -> Color = { original -> BlackScrim.compositeOver(original) }