PositionedDirectional class
A widget that controls where a child of a Stack is positioned without committing to a specific TextDirection.
The ambient Directionality is used to determine whether start is to the left or to the right.
A PositionedDirectional widget must be a descendant of a Stack, and the path from the PositionedDirectional widget to its enclosing Stack must contain only StatelessWidgets or StatefulWidgets (not other kinds of widgets, like RenderObjectWidgets).
If a widget is wrapped in a PositionedDirectional, then it is a positioned widget in its Stack. If the top property is non-null, the top edge of this child/ will be positioned top layout units from the top of the stack widget. The start, bottom, and end properties work analogously.
If both the top and bottom properties are non-null, then the child will be forced to have exactly the height required to satisfy both constraints. Similarly, setting the start and end properties to non-null values will force the child to have a particular width. Alternatively the width and height properties can be used to give the dimensions, with one corresponding position property (e.g. top and height).
See also:
- Positioned, which specifies the widget's position visually.
- Positioned.directional, which also specifies the widget's horizontal position using start and end but has an explicit TextDirection.
- Inheritance
- Object
- Diagnosticable
- DiagnosticableTree
- Widget
- StatelessWidget
- PositionedDirectional
Constructors
Properties
- bottom → double
-
The distance that the child's bottom edge is inset from the bottom of the stack. [...]
final
- child → Widget
-
The widget below this widget in the tree. [...]
final
- end → double
-
The distance that the child's trailing edge is inset from the trailing
edge of the stack. [...]
final
- height → double
-
The child's height. [...]
final
- start → double
-
The distance that the child's leading edge is inset from the leading edge
of the stack. [...]
final
- top → double
-
The distance that the child's top edge is inset from the top of the stack. [...]
final
- width → double
-
The child's width. [...]
final
- hashCode → int
-
The hash code for this object. [...]
read-only, inherited
- key → Key
-
Controls how one widget replaces another widget in the tree. [...]
final, inherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
Methods
-
build(
BuildContext context) → Widget -
Describes the part of the user interface represented by this widget. [...]
override
-
createElement(
) → StatelessElement -
Creates a StatelessElement to manage this widget's location in the tree. [...]
inherited
-
debugDescribeChildren(
) → List< DiagnosticsNode> -
Returns a list of DiagnosticsNode objects describing this node's
children. [...]
@protected, inherited
-
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
-
toDiagnosticsNode(
{String name, DiagnosticsTreeStyle style }) → DiagnosticsNode -
Returns a debug representation of the object that is used by debugging
tools and by toStringDeep. [...]
inherited
-
toString(
{DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String -
Returns 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 ==(
dynamic other) → bool -
The equality operator. [...]
inherited