<itemvalue="The number of device pixels for each logical pixel for the screen this view is displayed on. 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. Device pixels are also referred to as physical pixels. Logical pixels are also referred to as device-independent or resolution-independent pixels. By definition, there are roughly 38 logical pixels per centimeter, or about 96 logical pixels per inch, of the physical display. The value returned by [devicePixelRatio] is ultimately obtained either from the hardware itself, the device drivers, or a hard-coded value stored in the operating system or firmware, and may be inaccurate, sometimes by a significant margin. The Flutter framework operates in logical pixels, so it is rarely necessary to directly deal with this property. When this changes, [PlatformDispatcher.onMetricsChanged] is called. When using the Flutter framework, using [MediaQuery.of] to obtain the device pixel ratio (via [MediaQueryData.devicePixelRatio]), instead of directly obtaining the [devicePixelRatio] from a [FlutterView], will automatically cause any widgets dependent on this value to rebuild when it changes, without having to listen to [PlatformDispatcher.onMetricsChanged]. See also: [WidgetsBindingObserver], for a mechanism at the widgets layer to observe when this value changes. [Display.devicePixelRatio], which reports the DPR of the display. The value here is equal to the value exposed on [display]."/>
<itemvalue="Subsequent version, remove this deprecated member. ignore: deprecated_member_use"/>
<itemvalue="Dynamically loads the |EnableNonClientDpiScaling| from the User32 module. This API is only needed for PerMonitor V1 awareness mode."/>
<itemvalue="[ThemeData.visualDensity], where this property is used to specify the base horizontal density of Material components. [Material design guidance on density]"/>
<itemvalue="Defines the visual density of user interface components. Density, in the context of a UI, is the vertical and horizontal "compactness" of the components in the UI. It is unitless, since it means different things to different UI components. The default for visual densities is zero for both vertical and horizontal densities, which corresponds to the default visual density of components in the Material Design specification. It does not affect text sizes, icon sizes, or padding values. For example, for buttons, it affects the spacing around the child of the button. For lists, it affects the distance between baselines of entries in the list. For chips, it only affects the vertical size, not the horizontal size."/>
dx
1 year ago