Implement fullscreen mode in new reader

app/src/main/kotlin/com/google/accompanist/systemuicontroller/SystemUiController.kt

@@ -0,0 +1,152 @@
+/*
+ * 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
+ *
+ *      https://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.google.accompanist.systemuicontroller
+
+import android.app.Activity
+import android.content.Context
+import android.content.ContextWrapper
+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.platform.LocalView
+import androidx.compose.ui.window.DialogWindowProvider
+import androidx.core.view.ViewCompat
+import androidx.core.view.WindowCompat
+import androidx.core.view.WindowInsetsCompat
+import androidx.core.view.WindowInsetsControllerCompat
+
+/**
+ * A class which provides easy-to-use utilities for updating the System UI bar
+ * colors within Jetpack Compose.
+ */
+@Stable
+interface SystemUiController {
+
+    /**
+     * Control for the behavior of the system bars. This value should be one of the
+     * [WindowInsetsControllerCompat] behavior constants:
+     * [WindowInsetsControllerCompat.BEHAVIOR_SHOW_BARS_BY_TOUCH] (Deprecated),
+     * [WindowInsetsControllerCompat.BEHAVIOR_DEFAULT] and
+     * [WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE].
+     */
+    var systemBarsBehavior: Int
+
+    /**
+     * 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
+        }
+}
+
+/**
+ * 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,
+    window: Window?,
+) : SystemUiController {
+    private val windowInsetsController = window?.let {
+        WindowCompat.getInsetsController(it, view)
+    }
+
+    override var systemBarsBehavior: Int
+        get() = windowInsetsController?.systemBarsBehavior ?: 0
+        set(value) {
+            windowInsetsController?.systemBarsBehavior = value
+        }
+
+    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())
+            }
+        }
+}

app/src/main/kotlin/com/hippo/ehviewer/ui/reader/GalleryPager.kt

@@ -3,10 +3,8 @@ package com.hippo.ehviewer.ui.reader
 import androidx.compose.foundation.combinedClickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.WindowInsets
-import androidx.compose.foundation.layout.asPaddingValues
+import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.systemBars
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.foundation.lazy.items
@@ -42,6 +40,7 @@ fun GalleryPager(
     onSelectPage: (ReaderPage) -> Unit,
     onMenuRegionClick: () -> Unit,
     modifier: Modifier = Modifier,
+    contentPadding: PaddingValues = PaddingValues(0.dp),
 ) {
     val items = pageLoader.pages
     when (type) {
@@ -49,7 +48,7 @@ fun GalleryPager(
             HorizontalPager(
                 state = pagerState,
                 modifier = modifier,
-                contentPadding = WindowInsets.systemBars.asPaddingValues(),
+                contentPadding = contentPadding,
                 reverseLayout = type == RIGHT_TO_LEFT,
                 key = { it },
             ) { index ->
@@ -86,7 +85,7 @@ fun GalleryPager(
             VerticalPager(
                 state = pagerState,
                 modifier = modifier,
-                contentPadding = WindowInsets.systemBars.asPaddingValues(),
+                contentPadding = contentPadding,
                 key = { it },
             ) { index ->
                 val page = items[index]
@@ -137,7 +136,7 @@ fun GalleryPager(
                     },
                 ),
                 state = lazyListState,
-                contentPadding = WindowInsets.systemBars.asPaddingValues(),
+                contentPadding = contentPadding,
                 verticalArrangement = Arrangement.spacedBy(if (type != WEBTOON) 15.dp else 0.dp),
             ) {
                 items(items, key = { it.index }) { page ->

app/src/main/kotlin/com/hippo/ehviewer/ui/reader/ReaderScreen.kt

@@ -4,12 +4,16 @@ import androidx.compose.animation.animateColorAsState
 import androidx.compose.foundation.background
 import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.PaddingValues
 import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.WindowInsetsSides
+import androidx.compose.foundation.layout.asPaddingValues
+import androidx.compose.foundation.layout.displayCutout
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.navigationBarsPadding
 import androidx.compose.foundation.layout.only
 import androidx.compose.foundation.layout.safeDrawing
+import androidx.compose.foundation.layout.systemBars
 import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.foundation.pager.rememberPagerState
@@ -27,11 +31,15 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
+import androidx.compose.runtime.snapshotFlow
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.BlendMode
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.colorResource
+import androidx.compose.ui.unit.dp
+import androidx.core.view.WindowInsetsControllerCompat
+import com.google.accompanist.systemuicontroller.rememberSystemUiController
 import com.hippo.ehviewer.R
 import com.hippo.ehviewer.Settings
 import com.hippo.ehviewer.client.data.BaseGalleryInfo
@@ -79,6 +87,16 @@ fun ReaderScreen(info: BaseGalleryInfo, page: Int = -1, navigator: DestinationsN
     val showSeekbar by Settings.showReaderSeekbar.collectAsState()
     val readingMode by Settings.readingMode.collectAsState { ReadingModeType.fromPreference(it) }
     val volumeKeysEnabled by Settings.readWithVolumeKeys.collectAsState()
+    val fullscreen by Settings.fullscreen.collectAsState()
+    val cutoutShort by Settings.cutoutShort.collectAsState()
+    val uiController = rememberSystemUiController()
+    DisposableEffect(uiController) {
+        uiController.systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
+        onDispose {
+            uiController.isSystemBarsVisible = true
+            uiController.systemBarsBehavior = WindowInsetsControllerCompat.BEHAVIOR_DEFAULT
+        }
+    }
     Deferred({ pageLoader.awaitReady() }) {
         val lazyListState = rememberLazyListState()
         val pagerState = rememberPagerState { pageLoader.size }
@@ -87,6 +105,13 @@ fun ReaderScreen(info: BaseGalleryInfo, page: Int = -1, navigator: DestinationsN
         Box {
             var appbarVisible by remember { mutableStateOf(false) }
             val bgColor by collectBackgroundColorAsState()
+            if (fullscreen) {
+                LaunchedEffect(Unit) {
+                    snapshotFlow { appbarVisible }.collect {
+                        uiController.isSystemBarsVisible = it
+                    }
+                }
+            }
             VolumeKeysHandler(
                 enabled = { volumeKeysEnabled && !appbarVisible },
                 movePrevious = { syncState.sliderScrollTo(syncState.sliderValue - 1) },
@@ -125,6 +150,15 @@ fun ReaderScreen(info: BaseGalleryInfo, page: Int = -1, navigator: DestinationsN
                 },
                 onMenuRegionClick = { appbarVisible = !appbarVisible },
                 modifier = Modifier.background(bgColor),
+                contentPadding = if (fullscreen) {
+                    if (cutoutShort) {
+                        PaddingValues(0.dp)
+                    } else {
+                        WindowInsets.displayCutout.asPaddingValues()
+                    }
+                } else {
+                    WindowInsets.systemBars.asPaddingValues()
+                },
             )
             val brightness by Settings.customBrightness.collectAsState()
             val brightnessValue by Settings.customBrightnessValue.collectAsState()