CupertinoNavigationBar class Null safety
An iOS-styled navigation bar.
The navigation bar is a toolbar that minimally consists of a widget, normally a page title, in the middle of the toolbar.
It also supports a leading and trailing widget before and after the middle widget while keeping the middle widget centered.
The leading widget will automatically be a back chevron icon button (or a close button in case of a fullscreen dialog) to pop the current route if none is provided and automaticallyImplyLeading is true (true by default).
The middle widget will automatically be a title text from the current CupertinoPageRoute if none is provided and automaticallyImplyMiddle is true (true by default).
It should be placed at top of the screen and automatically accounts for the OS's status bar.
If the given backgroundColor's opacity is not 1.0 (which is the case by default), it will produce a blurring effect to the content behind it.
When transitionBetweenRoutes is true, this navigation bar will transition on top of the routes instead of inside them if the route being transitioned to also has a CupertinoNavigationBar or a CupertinoSliverNavigationBar with transitionBetweenRoutes set to true. If transitionBetweenRoutes is true, none of the Widget parameters can contain a key in its subtree since that widget will exist in multiple places in the tree simultaneously.
By default, only one CupertinoNavigationBar or CupertinoSliverNavigationBar should be present in each PageRoute to support the default transitions. Use transitionBetweenRoutes or heroTag to customize the transition behavior for multiple navigation bars per route.
When used in a CupertinoPageScaffold, CupertinoPageScaffold.navigationBar
has its text scale factor set to 1.0 and does not respond to text scale factor
changes from the operating system, to match the native iOS behavior. To override
this behavior, wrap each of the navigationBar
's components inside a MediaQuery
with the desired MediaQueryData.textScaleFactor value. The text scale factor
value from the operating system can be retrieved in many ways, such as querying
MediaQuery.textScaleFactorOf against CupertinoApp's BuildContext.
flutter create --sample=cupertino.CupertinoNavigationBar.1 mysample
See also:
- CupertinoPageScaffold, a page layout helper typically hosting the CupertinoNavigationBar.
- CupertinoSliverNavigationBar for a navigation bar to be placed in a scrolling list and that supports iOS-11-style large titles.
- developer.apple.com/design/human-interface-guidelines/ios/bars/navigation-bars/
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- CupertinoNavigationBar
- Implemented types
Constructors
-
Creates a navigation bar in the iOS style.
const
Properties
- automaticallyImplyLeading → bool
-
Controls whether we should try to imply the leading widget if null.
final
- automaticallyImplyMiddle → bool
-
Controls whether we should try to imply the middle widget if null.
final
- backgroundColor → Color?
-
The background color of the navigation bar. If it contains transparency, the
tab bar will automatically produce a blurring effect to the content
behind it.
final
- border → Border?
-
The border of the navigation bar. By default renders a single pixel bottom border side.
final
- brightness → Brightness?
-
The brightness of the specified backgroundColor.
final
- hashCode → int
- The hash code for this object.
- heroTag → Object
-
Tag for the navigation bar's Hero widget if transitionBetweenRoutes is true.
final
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- leading → Widget?
-
Widget to place at the start of the navigation bar. Normally a back button
for a normal page or a cancel button for full page dialogs.
final
- middle → Widget?
-
Widget to place in the middle of the navigation bar. Normally a title or
a segmented control.
final
- padding → EdgeInsetsDirectional?
-
Padding for the contents of the navigation bar.
final
- preferredSize → Size
-
The size this widget would prefer if it were otherwise unconstrained.
read-onlyoverride
- previousPageTitle → String?
-
Manually specify the previous route's title when automatically implying
the leading back button.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
read-onlyinherited
- trailing → Widget?
-
Widget to place at the end of the navigation bar. Normally additional actions
taken on the page such as a search or edit function.
final
- transitionBetweenRoutes → bool
-
Whether to transition between navigation bars.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< CupertinoNavigationBar> -
Creates the mutable state for this widget at a given location in the tree.
override
-
debugDescribeChildren(
) → List< DiagnosticsNode> -
Returns a list of
DiagnosticsNode
objects describing this node's children.protected">@protectedinherited -
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void -
Add additional properties associated with the node.
inherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.
inherited
-
shouldFullyObstruct(
BuildContext context) → bool -
True if the navigation bar's background color has no transparency.
override
-
toDiagnosticsNode(
{String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode -
Returns a debug representation of the object that is used by debugging
tools and by DiagnosticsNode.toStringDeep.
inherited
-
toString(
{DiagnosticLevel minLevel = DiagnosticLevel.info}) → String -
A string representation of this object.
inherited
-
toStringDeep(
{String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String -
Returns a string representation of this node and its descendants.
inherited
-
toStringShallow(
{String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String -
Returns a one-line detailed description of the object.
inherited
-
toStringShort(
) → String -
A short, textual description of this widget.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
nonVirtual">@nonVirtualinherited