// Copyright 2014 The Flutter Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. import 'dart:math' as math; import 'dart:ui' as ui; import 'dart:ui' show Brightness; import 'package:flutter/foundation.dart'; import 'basic.dart'; import 'debug.dart'; import 'framework.dart'; /// Whether in portrait or landscape. enum Orientation { /// Taller than wide. portrait, /// Wider than tall. landscape } /// Information about a piece of media (e.g., a window). /// /// For example, the [MediaQueryData.size] property contains the width and /// height of the current window. /// /// To obtain the current [MediaQueryData] for a given [BuildContext], use the /// [MediaQuery.of] function. For example, to obtain the size of the current /// window, use `MediaQuery.of(context).size`. /// /// If no [MediaQuery] is in scope then the [MediaQuery.of] method will throw an /// exception. Alternatively, [MediaQuery.maybeOf] may be used, which returns /// null instead of throwing if no [MediaQuery] is in scope. /// /// ## Insets and Padding /// /// ![A diagram of padding, viewInsets, and viewPadding in correlation with each /// other](https://flutter.github.io/assets-for-api-docs/assets/widgets/media_query.png) /// /// This diagram illustrates how [padding] relates to [viewPadding] and /// [viewInsets], shown here in its simplest configuration, as the difference /// between the two. In cases when the viewInsets exceed the viewPadding, like /// when a software keyboard is shown below, padding goes to zero rather than a /// negative value. Therefore, padding is calculated by taking /// `max(0.0, viewPadding - viewInsets)`. /// /// {@animation 300 300 https://flutter.github.io/assets-for-api-docs/assets/widgets/window_padding.mp4} /// /// In this diagram, the black areas represent system UI that the app cannot /// draw over. The red area represents view padding that the application may not /// be able to detect gestures in and may not want to draw in. The grey area /// represents the system keyboard, which can cover over the bottom view padding /// when visible. /// /// MediaQueryData includes three [EdgeInsets] values: /// [padding], [viewPadding], and [viewInsets]. These values reflect the /// configuration of the device and are used and optionally consumed by widgets /// that position content within these insets. The padding value defines areas /// that might not be completely visible, like the display "notch" on the iPhone /// X. The viewInsets value defines areas that aren't visible at all, typically /// because they're obscured by the device's keyboard. Similar to viewInsets, /// viewPadding does not differentiate padding in areas that may be obscured. /// For example, by using the viewPadding property, padding would defer to the /// iPhone "safe area" regardless of whether a keyboard is showing. /// /// The viewInsets and viewPadding are independent values, they're /// measured from the edges of the MediaQuery widget's bounds. Together they /// inform the [padding] property. The bounds of the top level MediaQuery /// created by [WidgetsApp] are the same as the window that contains the app. /// /// Widgets whose layouts consume space defined by [viewInsets], [viewPadding], /// or [padding] should enclose their children in secondary MediaQuery /// widgets that reduce those properties by the same amount. /// The [removePadding], [removeViewPadding], and [removeViewInsets] methods are /// useful for this. /// /// See also: /// /// * [Scaffold], [SafeArea], [CupertinoTabScaffold], and /// [CupertinoPageScaffold], all of which are informed by [padding], /// [viewPadding], and [viewInsets]. @immutable class MediaQueryData { /// Creates data for a media query with explicit values. /// /// Consider using [MediaQueryData.fromWindow] to create data based on a /// [dart:ui.PlatformDispatcher]. const MediaQueryData({ this.size = Size.zero, this.devicePixelRatio = 1.0, this.textScaleFactor = 1.0, this.platformBrightness = Brightness.light, this.padding = EdgeInsets.zero, this.viewInsets = EdgeInsets.zero, this.systemGestureInsets = EdgeInsets.zero, this.viewPadding = EdgeInsets.zero, this.alwaysUse24HourFormat = false, this.accessibleNavigation = false, this.invertColors = false, this.highContrast = false, this.disableAnimations = false, this.boldText = false, this.navigationMode = NavigationMode.traditional, }) : assert(size != null), assert(devicePixelRatio != null), assert(textScaleFactor != null), assert(platformBrightness != null), assert(padding != null), assert(viewInsets != null), assert(systemGestureInsets != null), assert(viewPadding != null), assert(alwaysUse24HourFormat != null), assert(accessibleNavigation != null), assert(invertColors != null), assert(highContrast != null), assert(disableAnimations != null), assert(boldText != null), assert(navigationMode != null); /// Creates data for a media query based on the given window. /// /// If you use this, you should ensure that you also register for /// notifications so that you can update your [MediaQueryData] when the /// window's metrics change. For example, see /// [WidgetsBindingObserver.didChangeMetrics] or /// [dart:ui.PlatformDispatcher.onMetricsChanged]. MediaQueryData.fromWindow(ui.SingletonFlutterWindow window) : size = window.physicalSize / window.devicePixelRatio, devicePixelRatio = window.devicePixelRatio, textScaleFactor = window.textScaleFactor, platformBrightness = window.platformBrightness, padding = EdgeInsets.fromWindowPadding(window.padding, window.devicePixelRatio), viewPadding = EdgeInsets.fromWindowPadding(window.viewPadding, window.devicePixelRatio), viewInsets = EdgeInsets.fromWindowPadding(window.viewInsets, window.devicePixelRatio), systemGestureInsets = EdgeInsets.fromWindowPadding(window.systemGestureInsets, window.devicePixelRatio), accessibleNavigation = window.accessibilityFeatures.accessibleNavigation, invertColors = window.accessibilityFeatures.invertColors, disableAnimations = window.accessibilityFeatures.disableAnimations, boldText = window.accessibilityFeatures.boldText, highContrast = window.accessibilityFeatures.highContrast, alwaysUse24HourFormat = window.alwaysUse24HourFormat, navigationMode = NavigationMode.traditional; /// The size of the media in logical pixels (e.g, the size of the screen). /// /// Logical pixels are roughly the same visual size across devices. Physical /// pixels are the size of the actual hardware pixels on the device. The /// number of physical pixels per logical pixel is described by the /// [devicePixelRatio]. final Size size; /// The number of device pixels for each logical pixel. This number might not /// be a power of two. Indeed, it might not even be an integer. For example, /// the Nexus 6 has a device pixel ratio of 3.5. final double devicePixelRatio; /// The number of font pixels for each logical pixel. /// /// For example, if the text scale factor is 1.5, text will be 50% larger than /// the specified font size. /// /// See also: /// /// * [MediaQuery.textScaleFactorOf], a convenience method which returns the /// textScaleFactor defined for a [BuildContext]. final double textScaleFactor; /// The current brightness mode of the host platform. /// /// For example, starting in Android Pie, battery saver mode asks all apps to /// render in a "dark mode". /// /// Not all platforms necessarily support a concept of brightness mode. Those /// platforms will report [Brightness.light] in this property. final Brightness platformBrightness; /// The parts of the display that are completely obscured by system UI, /// typically by the device's keyboard. /// /// When a mobile device's keyboard is visible `viewInsets.bottom` /// corresponds to the top of the keyboard. /// /// This value is independent of the [padding] and [viewPadding]. viewPadding /// is measured from the edges of the [MediaQuery] widget's bounds. Padding is /// calculated based on the viewPadding and viewInsets. The bounds of the top /// level MediaQuery created by [WidgetsApp] are the same as the window /// (often the mobile device screen) that contains the app. /// /// See also: /// /// * [ui.window], which provides some additional detail about this property /// and how it relates to [padding] and [viewPadding]. final EdgeInsets viewInsets; /// The parts of the display that are partially obscured by system UI, /// typically by the hardware display "notches" or the system status bar. /// /// If you consumed this padding (e.g. by building a widget that envelops or /// accounts for this padding in its layout in such a way that children are /// no longer exposed to this padding), you should remove this padding /// for subsequent descendants in the widget tree by inserting a new /// [MediaQuery] widget using the [MediaQuery.removePadding] factory. /// /// Padding is derived from the values of [viewInsets] and [viewPadding]. /// /// See also: /// /// * [ui.window], which provides some additional detail about this /// property and how it relates to [viewInsets] and [viewPadding]. /// * [SafeArea], a widget that consumes this padding with a [Padding] widget /// and automatically removes it from the [MediaQuery] for its child. final EdgeInsets padding; /// The parts of the display that are partially obscured by system UI, /// typically by the hardware display "notches" or the system status bar. /// /// This value remains the same regardless of whether the system is reporting /// other obstructions in the same physical area of the screen. For example, a /// software keyboard on the bottom of the screen that may cover and consume /// the same area that requires bottom padding will not affect this value. /// /// This value is independent of the [padding] and [viewInsets]: their values /// are measured from the edges of the [MediaQuery] widget's bounds. The /// bounds of the top level MediaQuery created by [WidgetsApp] are the /// same as the window that contains the app. On mobile devices, this will /// typically be the full screen. /// /// See also: /// /// * [ui.window], which provides some additional detail about this /// property and how it relates to [padding] and [viewInsets]. final EdgeInsets viewPadding; /// The areas along the edges of the display where the system consumes /// certain input events and blocks delivery of those events to the app. /// /// Starting with Android Q, simple swipe gestures that start within the /// [systemGestureInsets] areas are used by the system for page navigation /// and may not be delivered to the app. Taps and swipe gestures that begin /// with a long-press are delivered to the app, but simple press-drag-release /// swipe gestures which begin within the area defined by [systemGestureInsets] /// may not be. /// /// Apps should avoid locating gesture detectors within the system gesture /// insets area. Apps should feel free to put visual elements within /// this area. /// /// This property is currently only expected to be set to a non-default value /// on Android starting with version Q. /// /// {@tool dartpad --template=stateful_widget_material} /// /// For apps that might be deployed on Android Q devices with full gesture /// navigation enabled, use [systemGestureInsets] with [Padding] /// to avoid having the left and right edges of the [Slider] from appearing /// within the area reserved for system gesture navigation. /// /// By default, [Slider]s expand to fill the available width. So, we pad the /// left and right sides. /// /// ```dart /// double _currentValue = 0.2; /// /// @override /// Widget build(BuildContext context) { /// EdgeInsets systemGestureInsets = MediaQuery.of(context).systemGestureInsets; /// return Scaffold( /// appBar: AppBar(title: Text('Pad Slider to avoid systemGestureInsets')), /// body: Padding( /// padding: EdgeInsets.only( // only left and right padding are needed here /// left: systemGestureInsets.left, /// right: systemGestureInsets.right, /// ), /// child: Slider( /// value: _currentValue.toDouble(), /// onChanged: (double newValue) { /// setState(() { /// _currentValue = newValue; /// }); /// }, /// ), /// ), /// ); /// } /// ``` /// {@end-tool} final EdgeInsets systemGestureInsets; /// Whether to use 24-hour format when formatting time. /// /// The behavior of this flag is different across platforms: /// /// - On Android this flag is reported directly from the user settings called /// "Use 24-hour format". It applies to any locale used by the application, /// whether it is the system-wide locale, or the custom locale set by the /// application. /// - On iOS this flag is set to true when the user setting called "24-Hour /// Time" is set or the system-wide locale's default uses 24-hour /// formatting. final bool alwaysUse24HourFormat; /// Whether the user is using an accessibility service like TalkBack or /// VoiceOver to interact with the application. /// /// When this setting is true, features such as timeouts should be disabled or /// have minimum durations increased. /// /// See also: /// /// * [dart:ui.PlatformDispatcher.accessibilityFeatures], where the setting originates. final bool accessibleNavigation; /// Whether the device is inverting the colors of the platform. /// /// This flag is currently only updated on iOS devices. /// /// See also: /// /// * [dart:ui.PlatformDispatcher.accessibilityFeatures], where the setting /// originates. final bool invertColors; /// Whether the user requested a high contrast between foreground and background /// content on iOS, via Settings -> Accessibility -> Increase Contrast. /// /// This flag is currently only updated on iOS devices that are running iOS 13 /// or above. final bool highContrast; /// Whether the platform is requesting that animations be disabled or reduced /// as much as possible. /// /// See also: /// /// * [dart:ui.PlatformDispatcher.accessibilityFeatures], where the setting /// originates. final bool disableAnimations; /// Whether the platform is requesting that text be drawn with a bold font /// weight. /// /// See also: /// /// * [dart:ui.PlatformDispatcher.accessibilityFeatures], where the setting /// originates. final bool boldText; /// Describes the navigation mode requested by the platform. /// /// Some user interfaces are better navigated using a directional pad (DPAD) /// or arrow keys, and for those interfaces, some widgets need to handle these /// directional events differently. In order to know when to do that, these /// widgets will look for the navigation mode in effect for their context. /// /// For instance, in a television interface, [NavigationMode.directional] /// should be set, so that directional navigation is used to navigate away /// from a text field using the DPAD. In contrast, on a regular desktop /// application with the `navigationMode` set to [NavigationMode.traditional], /// the arrow keys are used to move the cursor instead of navigating away. /// /// The [NavigationMode] values indicate the type of navigation to be used in /// a widget subtree for those widgets sensitive to it. final NavigationMode navigationMode; /// The orientation of the media (e.g., whether the device is in landscape or /// portrait mode). Orientation get orientation { return size.width > size.height ? Orientation.landscape : Orientation.portrait; } /// Creates a copy of this media query data but with the given fields replaced /// with the new values. MediaQueryData copyWith({ Size? size, double? devicePixelRatio, double? textScaleFactor, Brightness? platformBrightness, EdgeInsets? padding, EdgeInsets? viewPadding, EdgeInsets? viewInsets, EdgeInsets? systemGestureInsets, bool? alwaysUse24HourFormat, bool? highContrast, bool? disableAnimations, bool? invertColors, bool? accessibleNavigation, bool? boldText, NavigationMode? navigationMode, }) { return MediaQueryData( size: size ?? this.size, devicePixelRatio: devicePixelRatio ?? this.devicePixelRatio, textScaleFactor: textScaleFactor ?? this.textScaleFactor, platformBrightness: platformBrightness ?? this.platformBrightness, padding: padding ?? this.padding, viewPadding: viewPadding ?? this.viewPadding, viewInsets: viewInsets ?? this.viewInsets, systemGestureInsets: systemGestureInsets ?? this.systemGestureInsets, alwaysUse24HourFormat: alwaysUse24HourFormat ?? this.alwaysUse24HourFormat, invertColors: invertColors ?? this.invertColors, highContrast: highContrast ?? this.highContrast, disableAnimations: disableAnimations ?? this.disableAnimations, accessibleNavigation: accessibleNavigation ?? this.accessibleNavigation, boldText: boldText ?? this.boldText, navigationMode: navigationMode ?? this.navigationMode, ); } /// Creates a copy of this media query data but with the given [padding]s /// replaced with zero. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then this /// [MediaQueryData] is returned unmodified. /// /// See also: /// /// * [MediaQuery.removePadding], which uses this method to remove [padding] /// from the ambient [MediaQuery]. /// * [SafeArea], which both removes the padding from the [MediaQuery] and /// adds a [Padding] widget. /// * [removeViewInsets], the same thing but for [viewInsets]. /// * [removeViewPadding], the same thing but for [viewPadding]. MediaQueryData removePadding({ bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, }) { if (!(removeLeft || removeTop || removeRight || removeBottom)) return this; return MediaQueryData( size: size, devicePixelRatio: devicePixelRatio, textScaleFactor: textScaleFactor, platformBrightness: platformBrightness, padding: padding.copyWith( left: removeLeft ? 0.0 : null, top: removeTop ? 0.0 : null, right: removeRight ? 0.0 : null, bottom: removeBottom ? 0.0 : null, ), viewPadding: viewPadding.copyWith( left: removeLeft ? math.max(0.0, viewPadding.left - padding.left) : null, top: removeTop ? math.max(0.0, viewPadding.top - padding.top) : null, right: removeRight ? math.max(0.0, viewPadding.right - padding.right) : null, bottom: removeBottom ? math.max(0.0, viewPadding.bottom - padding.bottom) : null, ), viewInsets: viewInsets, alwaysUse24HourFormat: alwaysUse24HourFormat, highContrast: highContrast, disableAnimations: disableAnimations, invertColors: invertColors, accessibleNavigation: accessibleNavigation, boldText: boldText, ); } /// Creates a copy of this media query data but with the given [viewInsets] /// replaced with zero. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then this /// [MediaQueryData] is returned unmodified. /// /// See also: /// /// * [MediaQuery.removeViewInsets], which uses this method to remove /// [viewInsets] from the ambient [MediaQuery]. /// * [removePadding], the same thing but for [padding]. /// * [removeViewPadding], the same thing but for [viewPadding]. MediaQueryData removeViewInsets({ bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, }) { if (!(removeLeft || removeTop || removeRight || removeBottom)) return this; return MediaQueryData( size: size, devicePixelRatio: devicePixelRatio, textScaleFactor: textScaleFactor, platformBrightness: platformBrightness, padding: padding, viewPadding: viewPadding.copyWith( left: removeLeft ? math.max(0.0, viewPadding.left - viewInsets.left) : null, top: removeTop ? math.max(0.0, viewPadding.top - viewInsets.top) : null, right: removeRight ? math.max(0.0, viewPadding.right - viewInsets.right) : null, bottom: removeBottom ? math.max(0.0, viewPadding.bottom - viewInsets.bottom) : null, ), viewInsets: viewInsets.copyWith( left: removeLeft ? 0.0 : null, top: removeTop ? 0.0 : null, right: removeRight ? 0.0 : null, bottom: removeBottom ? 0.0 : null, ), alwaysUse24HourFormat: alwaysUse24HourFormat, highContrast: highContrast, disableAnimations: disableAnimations, invertColors: invertColors, accessibleNavigation: accessibleNavigation, boldText: boldText, ); } /// Creates a copy of this media query data but with the given [viewPadding] /// replaced with zero. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then this /// [MediaQueryData] is returned unmodified. /// /// See also: /// /// * [MediaQuery.removeViewPadding], which uses this method to remove /// [viewPadding] from the ambient [MediaQuery]. /// * [removePadding], the same thing but for [padding]. /// * [removeViewInsets], the same thing but for [viewInsets]. MediaQueryData removeViewPadding({ bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, }) { if (!(removeLeft || removeTop || removeRight || removeBottom)) return this; return MediaQueryData( size: size, devicePixelRatio: devicePixelRatio, textScaleFactor: textScaleFactor, platformBrightness: platformBrightness, padding: padding.copyWith( left: removeLeft ? 0.0 : null, top: removeTop ? 0.0 : null, right: removeRight ? 0.0 : null, bottom: removeBottom ? 0.0 : null, ), viewInsets: viewInsets, viewPadding: viewPadding.copyWith( left: removeLeft ? 0.0 : null, top: removeTop ? 0.0 : null, right: removeRight ? 0.0 : null, bottom: removeBottom ? 0.0 : null, ), alwaysUse24HourFormat: alwaysUse24HourFormat, highContrast: highContrast, disableAnimations: disableAnimations, invertColors: invertColors, accessibleNavigation: accessibleNavigation, boldText: boldText, ); } @override bool operator ==(Object other) { if (other.runtimeType != runtimeType) return false; return other is MediaQueryData && other.size == size && other.devicePixelRatio == devicePixelRatio && other.textScaleFactor == textScaleFactor && other.platformBrightness == platformBrightness && other.padding == padding && other.viewPadding == viewPadding && other.viewInsets == viewInsets && other.alwaysUse24HourFormat == alwaysUse24HourFormat && other.highContrast == highContrast && other.disableAnimations == disableAnimations && other.invertColors == invertColors && other.accessibleNavigation == accessibleNavigation && other.boldText == boldText && other.navigationMode == navigationMode; } @override int get hashCode { return hashValues( size, devicePixelRatio, textScaleFactor, platformBrightness, padding, viewPadding, viewInsets, alwaysUse24HourFormat, highContrast, disableAnimations, invertColors, accessibleNavigation, boldText, navigationMode, ); } @override String toString() { final List<String> properties = <String>[ 'size: $size', 'devicePixelRatio: ${devicePixelRatio.toStringAsFixed(1)}', 'textScaleFactor: ${textScaleFactor.toStringAsFixed(1)}', 'platformBrightness: $platformBrightness', 'padding: $padding', 'viewPadding: $viewPadding', 'viewInsets: $viewInsets', 'alwaysUse24HourFormat: $alwaysUse24HourFormat', 'accessibleNavigation: $accessibleNavigation', 'highContrast: $highContrast', 'disableAnimations: $disableAnimations', 'invertColors: $invertColors', 'boldText: $boldText', 'navigationMode: ${describeEnum(navigationMode)}', ]; return '${objectRuntimeType(this, 'MediaQueryData')}(${properties.join(', ')})'; } } /// Establishes a subtree in which media queries resolve to the given data. /// /// For example, to learn the size of the current media (e.g., the window /// containing your app), you can read the [MediaQueryData.size] property from /// the [MediaQueryData] returned by [MediaQuery.of]: /// `MediaQuery.of(context).size`. /// /// Querying the current media using [MediaQuery.of] will cause your widget to /// rebuild automatically whenever the [MediaQueryData] changes (e.g., if the /// user rotates their device). /// /// If no [MediaQuery] is in scope then the [MediaQuery.of] method will throw an /// exception. Alternatively, [MediaQuery.maybeOf] may be used, which returns /// null instead of throwing if no [MediaQuery] is in scope. /// /// {@youtube 560 315 https://www.youtube.com/watch?v=A3WrA4zAaPw} /// /// See also: /// /// * [WidgetsApp] and [MaterialApp], which introduce a [MediaQuery] and keep /// it up to date with the current screen metrics as they change. /// * [MediaQueryData], the data structure that represents the metrics. class MediaQuery extends InheritedWidget { /// Creates a widget that provides [MediaQueryData] to its descendants. /// /// The [data] and [child] arguments must not be null. const MediaQuery({ Key? key, required this.data, required Widget child, }) : assert(child != null), assert(data != null), super(key: key, child: child); /// Creates a new [MediaQuery] that inherits from the ambient [MediaQuery] /// from the given context, but removes the specified padding. /// /// This should be inserted into the widget tree when the [MediaQuery] padding /// is consumed by a widget in such a way that the padding is no longer /// exposed to the widget's descendants or siblings. /// /// The [context] argument is required, must not be null, and must have a /// [MediaQuery] in scope. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then the returned /// [MediaQuery] reuses the ambient [MediaQueryData] unmodified, which is not /// particularly useful. /// /// The [child] argument is required and must not be null. /// /// See also: /// /// * [SafeArea], which both removes the padding from the [MediaQuery] and /// adds a [Padding] widget. /// * [MediaQueryData.padding], the affected property of the /// [MediaQueryData]. /// * [removeViewInsets], the same thing but for [MediaQueryData.viewInsets]. /// * [removeViewPadding], the same thing but for /// [MediaQueryData.viewPadding]. factory MediaQuery.removePadding({ Key? key, required BuildContext context, bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, required Widget child, }) { return MediaQuery( key: key, data: MediaQuery.of(context).removePadding( removeLeft: removeLeft, removeTop: removeTop, removeRight: removeRight, removeBottom: removeBottom, ), child: child, ); } /// Creates a new [MediaQuery] that inherits from the ambient [MediaQuery] /// from the given context, but removes the specified view insets. /// /// This should be inserted into the widget tree when the [MediaQuery] view /// insets are consumed by a widget in such a way that the view insets are no /// longer exposed to the widget's descendants or siblings. /// /// The [context] argument is required, must not be null, and must have a /// [MediaQuery] in scope. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then the returned /// [MediaQuery] reuses the ambient [MediaQueryData] unmodified, which is not /// particularly useful. /// /// The [child] argument is required and must not be null. /// /// See also: /// /// * [MediaQueryData.viewInsets], the affected property of the /// [MediaQueryData]. /// * [removePadding], the same thing but for [MediaQueryData.padding]. /// * [removeViewPadding], the same thing but for /// [MediaQueryData.viewPadding]. factory MediaQuery.removeViewInsets({ Key? key, required BuildContext context, bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, required Widget child, }) { return MediaQuery( key: key, data: MediaQuery.of(context).removeViewInsets( removeLeft: removeLeft, removeTop: removeTop, removeRight: removeRight, removeBottom: removeBottom, ), child: child, ); } /// Creates a new [MediaQuery] that inherits from the ambient [MediaQuery] /// from the given context, but removes the specified view padding. /// /// This should be inserted into the widget tree when the [MediaQuery] view /// padding is consumed by a widget in such a way that the view padding is no /// longer exposed to the widget's descendants or siblings. /// /// The [context] argument is required, must not be null, and must have a /// [MediaQuery] in scope. /// /// The `removeLeft`, `removeTop`, `removeRight`, and `removeBottom` arguments /// must not be null. If all four are false (the default) then the returned /// [MediaQuery] reuses the ambient [MediaQueryData] unmodified, which is not /// particularly useful. /// /// The [child] argument is required and must not be null. /// /// See also: /// /// * [MediaQueryData.viewPadding], the affected property of the /// [MediaQueryData]. /// * [removePadding], the same thing but for [MediaQueryData.padding]. /// * [removeViewInsets], the same thing but for [MediaQueryData.viewInsets]. factory MediaQuery.removeViewPadding({ Key? key, required BuildContext context, bool removeLeft = false, bool removeTop = false, bool removeRight = false, bool removeBottom = false, required Widget child, }) { return MediaQuery( key: key, data: MediaQuery.of(context).removeViewPadding( removeLeft: removeLeft, removeTop: removeTop, removeRight: removeRight, removeBottom: removeBottom, ), child: child, ); } /// Contains information about the current media. /// /// For example, the [MediaQueryData.size] property contains the width and /// height of the current window. final MediaQueryData data; /// The data from the closest instance of this class that encloses the given /// context. /// /// You can use this function to query the size and orientation of the screen, /// as well as other media parameters (see [MediaQueryData] for more /// examples). When that information changes, your widget will be scheduled to /// be rebuilt, keeping your widget up-to-date. /// /// Typical usage is as follows: /// /// ```dart /// MediaQueryData media = MediaQuery.of(context); /// ``` /// /// If there is no [MediaQuery] in scope, this will throw a [TypeError] /// exception in release builds, and throw a descriptive [FlutterError] in /// debug builds. /// /// See also: /// /// * [maybeOf], which doesn't throw or assert if it doesn't find a /// [MediaQuery] ancestor, it returns null instead. static MediaQueryData of(BuildContext context) { assert(context != null); assert(debugCheckHasMediaQuery(context)); return context.dependOnInheritedWidgetOfExactType<MediaQuery>()!.data; } /// The data from the closest instance of this class that encloses the given /// context, if any. /// /// Use this function if you want to allow situations where no [MediaQuery] is /// in scope. Prefer using [MediaQuery.of] in situations where a media query /// is always expected to exist. /// /// If there is no [MediaQuery] in scope, then this function will return null. /// /// You can use this function to query the size and orientation of the screen, /// as well as other media parameters (see [MediaQueryData] for more /// examples). When that information changes, your widget will be scheduled to /// be rebuilt, keeping your widget up-to-date. /// /// Typical usage is as follows: /// /// ```dart /// MediaQueryData? mediaQuery = MediaQuery.maybeOf(context); /// if (mediaQuery == null) { /// // Do something else instead. /// } /// ``` /// /// See also: /// /// * [of], which will throw if it doesn't find a [MediaQuery] ancestor, /// instead of returning null. static MediaQueryData? maybeOf(BuildContext context) { assert(context != null); return context.dependOnInheritedWidgetOfExactType<MediaQuery>()?.data; } /// Returns textScaleFactor for the nearest MediaQuery ancestor or 1.0, if /// no such ancestor exists. static double textScaleFactorOf(BuildContext context) { return MediaQuery.maybeOf(context)?.textScaleFactor ?? 1.0; } /// Returns platformBrightness for the nearest MediaQuery ancestor or /// [Brightness.light], if no such ancestor exists. /// /// Use of this method will cause the given [context] to rebuild any time that /// any property of the ancestor [MediaQuery] changes. static Brightness platformBrightnessOf(BuildContext context) { return MediaQuery.maybeOf(context)?.platformBrightness ?? Brightness.light; } /// Returns highContrast for the nearest MediaQuery ancestor or false, if no /// such ancestor exists. /// /// See also: /// /// * [MediaQueryData.highContrast], which indicates the platform's /// desire to increase contrast. static bool highContrastOf(BuildContext context) { return MediaQuery.maybeOf(context)?.highContrast ?? false; } /// Returns the boldText accessibility setting for the nearest MediaQuery /// ancestor, or false if no such ancestor exists. static bool boldTextOverride(BuildContext context) { return MediaQuery.maybeOf(context)?.boldText ?? false; } @override bool updateShouldNotify(MediaQuery oldWidget) => data != oldWidget.data; @override void debugFillProperties(DiagnosticPropertiesBuilder properties) { super.debugFillProperties(properties); properties.add(DiagnosticsProperty<MediaQueryData>('data', data, showName: false)); } } /// Describes the navigation mode to be set by a [MediaQuery] widget. /// /// The different modes indicate the type of navigation to be used in a widget /// subtree for those widgets sensitive to it. /// /// Use `MediaQuery.of(context).navigationMode` to determine the navigation mode /// in effect for the given context. Use a [MediaQuery] widget to set the /// navigation mode for its descendant widgets. enum NavigationMode { /// This indicates a traditional keyboard-and-mouse navigation modality. /// /// This navigation mode is where the arrow keys can be used for secondary /// modification operations, like moving sliders or cursors, and disabled /// controls will lose focus and not be traversable. traditional, /// This indicates a directional-based navigation mode. /// /// This navigation mode indicates that arrow keys should be reserved for /// navigation operations, and secondary modifications operations, like moving /// sliders or cursors, will use alternative bindings or be disabled. /// /// Some behaviors are also affected by this mode. For instance, disabled /// controls will retain focus when disabled, and will be able to receive /// focus (although they remain disabled) when traversed. directional, }