Struct RenderIndexedStack 

pub struct RenderIndexedStack { /* private fields */ }

Implements the same layout algorithm as RenderStack but only paints the child specified by index.

Although only one child is displayed, the cost of the layout algorithm is still O(N), like an ordinary stack.

Implementations

impl RenderIndexedStack

pub fn new(app: &mut App) -> RenderHandle<RenderIndexedStack>

Creates a stack render object that paints a single child.

If index is set to None, nothing is displayed.

pub fn index(self: RenderHandle<Self>, app: &App) -> Option<i32>

The index of the child to show, None if nothing is to be displayed.

pub fn set_index(self: RenderHandle<Self>, app: &mut App, value: Option<i32>)

Sets index.

Trait Implementations

impl ContainerRenderObjectMixin for RenderIndexedStack

type ChildType = AnyRenderBox

Flutter’s ChildType: the protocol of this render object’s children.

type ParentDataType = StackParentData

Flutter’s ParentDataType: the parent data this render object installs on its children.

fn container_data( self: RenderHandle<Self>, app: &App, ) -> &ContainerRenderObjectData<AnyRenderBox>

Mixin field access.

fn container_data_mut( self: RenderHandle<Self>, app: &mut App, ) -> &mut ContainerRenderObjectData<AnyRenderBox>

See container_data.

fn child_count(self: RenderHandle<Self>, app: &App) -> usize

The number of children.

fn insert( self: RenderHandle<Self>, app: &mut App, child: Self::ChildType, after: Option<Self::ChildType>, )

Insert child into this render object’s child list after the given child.

fn add(self: RenderHandle<Self>, app: &mut App, child: Self::ChildType)

Append child to the end of this render object’s child list.

fn add_all( self: RenderHandle<Self>, app: &mut App, children: Option<Vec<Self::ChildType>>, )

Add all the children to the end of this render object’s child list.

fn remove(self: RenderHandle<Self>, app: &mut App, child: Self::ChildType)

Remove this child from the child list.

fn remove_all(self: RenderHandle<Self>, app: &mut App)

Remove all their children from this render object’s child list.

fn move_child( self: RenderHandle<Self>, app: &mut App, child: Self::ChildType, after: Option<Self::ChildType>, )

Move the given child in the child list to be after another child.

fn did_attach( self: RenderHandle<Self>, app: &mut App, owner: Handle<PipelineOwner>, )

The body of Flutter’s attach override: attaches every child in the list.

fn did_detach(self: RenderHandle<Self>, app: &mut App)

The body of Flutter’s detach override: detaches every child in the list.

fn redepth_children(self: RenderHandle<Self>, app: &mut App)

Flutter’s redepthChildren: walks the child list.

fn visit_children( self: RenderHandle<Self>, app: &App, visitor: &mut dyn FnMut(AnyRenderObject), )

Flutter’s visitChildren: walks the child list.

fn first_child(self: RenderHandle<Self>, app: &App) -> Option<Self::ChildType>

The first child in the child list.

fn last_child(self: RenderHandle<Self>, app: &App) -> Option<Self::ChildType>

The last child in the child list.

fn child_before( self: RenderHandle<Self>, app: &App, child: Self::ChildType, ) -> Option<Self::ChildType>

The previous child before the given child in the child list.

fn child_after( self: RenderHandle<Self>, app: &App, child: Self::ChildType, ) -> Option<Self::ChildType>

The next child after the given child in the child list.

fn children_as_list(self: RenderHandle<Self>, app: &App) -> Vec<Self::ChildType>

Returns a list containing the children of this render object.

impl RenderBox for RenderIndexedStack

fn compute_distance_to_actual_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, ) -> Option<f64>

The displayed child’s baseline.

fn compute_dry_baseline( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, baseline: TextBaseline, ) -> Option<f64>

The baseline the displayed child would have, measured dry.

fn render_box_data(self: RenderHandle<Self>, app: &App) -> &RenderBoxData

Mixin field access.

fn render_box_data_mut( self: RenderHandle<Self>, app: &mut App, ) -> &mut RenderBoxData

See render_box_data.

fn setup_parent_data( self: RenderHandle<Self>, app: &mut App, child: AnyRenderObject, )

Installs BoxParentData unless the child already has it.

fn compute_min_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

Computes the value returned by get_min_intrinsic_width. Do not call this function directly, instead, call get_min_intrinsic_width.

fn compute_max_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

Computes the value returned by get_max_intrinsic_width. Do not call this function directly, instead, call get_max_intrinsic_width.

fn compute_min_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

Computes the value returned by get_min_intrinsic_height. Do not call this function directly, instead, call get_min_intrinsic_height.

fn compute_max_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

Computes the value returned by get_max_intrinsic_height. Do not call this function directly, instead, call get_max_intrinsic_height.

fn compute_dry_layout( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, ) -> Size

Computes the value returned by get_dry_layout. Do not call this function directly, instead, call get_dry_layout.

fn hit_test_children( self: RenderHandle<Self>, app: &mut App, result: &mut BoxHitTestResult<'_>, position: Offset, ) -> bool

Override this method to check whether any children are located at the given position.

fn constraints(self: RenderHandle<Self>, app: &App) -> BoxConstraints

The box constraints most recently supplied by the parent.

fn get_min_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

See AnyRenderBox::get_min_intrinsic_width.

fn get_max_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

See AnyRenderBox::get_max_intrinsic_width.

fn get_min_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

See AnyRenderBox::get_min_intrinsic_height.

fn get_max_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

See AnyRenderBox::get_max_intrinsic_height.

fn get_dry_layout( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, ) -> Size

See AnyRenderBox::get_dry_layout.

fn get_dry_baseline( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, baseline: TextBaseline, ) -> Option<f64>

See AnyRenderBox::get_dry_baseline.

fn debug_cannot_compute_dry_layout( self: RenderHandle<Self>, failure: DryLayoutFailure<'_>, )

Called from compute_dry_layout or compute_dry_baseline if this box does not support calculating a dry layout.

fn get_distance_to_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, only_real: bool, ) -> Option<f64>

See AnyRenderBox::get_distance_to_baseline.

fn get_distance_to_actual_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, ) -> Option<f64>

See AnyRenderBox::get_distance_to_actual_baseline.

fn mark_needs_layout(self: RenderHandle<Self>, app: &mut App)

Mark this render object’s layout information as dirty.

fn perform_resize(self: RenderHandle<Self>, app: &mut App)

Updates the box’s size using only the constraints.

fn size(self: RenderHandle<Self>, app: &App) -> Size

The size of this box.

fn apply_paint_transform( self: RenderHandle<Self>, app: &App, child: AnyRenderObject, transform: &mut Matrix4, )

Multiply the transform from the parent’s coordinate system to this box’s coordinate system into the given transform.

fn paint_bounds(self: RenderHandle<Self>, app: &App) -> Rect

An estimate of the bounds within which this render object will paint: the box’s own size.

fn has_size(self: RenderHandle<Self>, app: &App) -> bool

Whether this render object has undergone layout and has a size.

fn handle_event( self: RenderHandle<Self>, app: &mut App, event: &PointerEvent, entry: &BoxHitTestEntry, )

Override this method to handle pointer events that hit this render object.

fn hit_test( self: RenderHandle<Self>, app: &mut App, result: &mut BoxHitTestResult<'_>, position: Offset, ) -> bool

Determines the set of render objects located at the given position.

fn hit_test_self( self: RenderHandle<Self>, _app: &App, _position: Offset, ) -> bool

Override this method if this render object can be hit even if its children were not hit.

fn set_size(self: RenderHandle<Self>, app: &mut App, size: Size)

Sets the size of this box. Call from RenderObject::perform_layout or RenderObject::perform_resize.

fn layout( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, parent_uses_size: bool, )

See AnyRenderBox::layout.

fn as_box(self: RenderHandle<Self>) -> AnyRenderBox

The type-erased RenderBox handle. Free: the vtable is a const, and the id is copied.

fn as_object(self: RenderHandle<Self>) -> AnyRenderObject

The type-erased RenderObject handle, through as_box.

fn adopt_child(self: RenderHandle<Self>, app: &mut App, child: AnyRenderObject)

See AnyRenderObject::adopt_child.

fn drop_child(self: RenderHandle<Self>, app: &mut App, child: AnyRenderObject)

See AnyRenderObject::drop_child.

fn mark_needs_paint(self: RenderHandle<Self>, app: &mut App)

See AnyRenderObject::mark_needs_paint.

fn mark_needs_composited_layer_update(self: RenderHandle<Self>, app: &mut App)

See AnyRenderObject::mark_needs_composited_layer_update.

fn mark_needs_compositing_bits_update(self: RenderHandle<Self>, app: &mut App)

See AnyRenderObject::mark_needs_compositing_bits_update.

fn schedule_initial_layout(self: RenderHandle<Self>, app: &mut App)

See AnyRenderObject::schedule_initial_layout.

fn parent(self: RenderHandle<Self>, app: &App) -> Option<AnyRenderObject>

See AnyRenderObject::parent.

fn owner(self: RenderHandle<Self>, app: &App) -> Option<Handle<PipelineOwner>>

See AnyRenderObject::owner.

fn attached(self: RenderHandle<Self>, app: &App) -> bool

See AnyRenderObject::attached.

fn debug_needs_layout(self: RenderHandle<Self>, app: &App) -> bool

See AnyRenderObject::debug_needs_layout.

impl RenderBoxContainerDefaultsMixin for RenderIndexedStack

fn default_compute_distance_to_first_actual_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, ) -> Option<f64>

Returns the baseline of the first child with a baseline.

fn default_compute_distance_to_highest_actual_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, ) -> Option<f64>

Returns the minimum baseline value among every child.

fn default_hit_test_children( self: RenderHandle<Self>, app: &mut App, result: &mut BoxHitTestResult<'_>, position: Offset, ) -> bool

Performs a hit test on each child by walking the child list backwards.

fn default_paint( self: RenderHandle<Self>, app: &mut App, context: &mut PaintingContext, offset: Offset, )

Paints each child by walking the child list forwards.

impl RenderObject for RenderIndexedStack

fn render_object_data(self: RenderHandle<Self>, app: &App) -> &RenderObjectData

Mixin field access.

fn render_object_data_mut( self: RenderHandle<Self>, app: &mut App, ) -> &mut RenderObjectData

See render_object_data.

fn perform_layout(self: RenderHandle<Self>, app: &mut App)

Do the work of computing the layout for this render object.

fn visit_children( self: RenderHandle<Self>, app: &App, visitor: &mut dyn FnMut(AnyRenderObject), )

Calls visitor for each immediate child.

fn did_attach( self: RenderHandle<Self>, app: &mut App, owner: Handle<PipelineOwner>, )

The body of Flutter’s attach override after super.attach(owner); the base body has already run. The default attaches the children reported by visit_children.

fn did_detach(self: RenderHandle<Self>, app: &mut App)

The body of Flutter’s detach override after super.detach(). The default detaches the children reported by visit_children.

fn redepth_children(self: RenderHandle<Self>, app: &mut App)

Adjusts the depth of each child reported by visit_children.

fn paint( self: RenderHandle<Self>, app: &mut App, context: &mut PaintingContext, offset: Offset, )

Paint this render object into the given context at the given offset.

fn dispose(self: RenderHandle<Self>, app: &mut App)

Release any resources held by this render object.

fn as_render_object(self: RenderHandle<Self>, app: &App) -> AnyRenderObject

Dart’s implicit upcast of a concrete render object to RenderObject: this object’s type-erased handle, through the vtable the protocol recorded when it created it.

fn perform_resize(self: RenderHandle<Self>, _app: &mut App)

Updates the render object’s size using only the constraints.

fn setup_parent_data( self: RenderHandle<Self>, app: &mut App, child: AnyRenderObject, )

Sets up parent data for child if it has none.

fn sized_by_parent(self: RenderHandle<Self>, _app: &App) -> bool

Whether the constraints are the only input to the sizing algorithm.

fn apply_paint_transform( self: RenderHandle<Self>, app: &App, child: AnyRenderObject, transform: &mut Matrix4, )

Applies the transform that would be applied when painting the given child to the given matrix.

fn is_repaint_boundary(self: RenderHandle<Self>, _app: &App) -> bool

Whether this render object repaints separately from its parent.

fn always_needs_compositing(self: RenderHandle<Self>, _app: &App) -> bool

Whether this render object always needs compositing.

fn mouse_tracker_annotation( self: RenderHandle<Self>, _app: &App, ) -> Option<MouseTrackerAnnotation>

Dart’s this is MouseTrackerAnnotation: the annotation this render object implements, read live each time the mouse tracker consults it. None for a render object that is not an annotation, which is the default.

fn update_composited_layer( self: RenderHandle<Self>, app: &mut App, old_layer: Option<AnyOffsetLayer>, ) -> AnyOffsetLayer

Update the composited layer owned by this render object.

fn show_on_screen( self: RenderHandle<Self>, app: &mut App, descendant: Option<AnyRenderObject>, rect: Option<Rect>, duration: Duration, curve: Rc<dyn Curve>, )

Attempt to make (a portion of) this or a descendant RenderObject visible on screen.

fn interface(self: RenderHandle<Self>, id: TypeId) -> Option<Box<dyn Any>>

Dart’s object is RenderAbstractViewport for any interface: the erased handle of the interface id names, if this type implements it.

impl RenderStackBase for RenderIndexedStack

fn stack_data(self: RenderHandle<Self>, app: &App) -> &RenderStackData

Mixin field access.

fn stack_data_mut( self: RenderHandle<Self>, app: &mut App, ) -> &mut RenderStackData

See stack_data.

fn paint_stack( self: RenderHandle<Self>, app: &mut App, context: &mut PaintingContext, offset: Offset, )

Override in subclasses to customize how the stack paints.

fn setup_parent_data( self: RenderHandle<Self>, app: &mut App, child: AnyRenderObject, )

Installs StackParentData unless the child already has it.

fn resolved_alignment(self: RenderHandle<Self>, app: &mut App) -> Alignment

The alignment resolved against text_direction, cached until either changes.

fn mark_need_resolution(self: RenderHandle<Self>, app: &mut App)

Drops the resolved alignment and marks layout dirty.

fn alignment(self: RenderHandle<Self>, app: &App) -> AlignmentGeometry

How to align the non-positioned or partially-positioned children in the stack.

fn set_alignment( self: RenderHandle<Self>, app: &mut App, value: AlignmentGeometry, )

Sets alignment.

fn text_direction(self: RenderHandle<Self>, app: &App) -> Option<TextDirection>

The text direction with which to resolve alignment.

fn set_text_direction( self: RenderHandle<Self>, app: &mut App, value: Option<TextDirection>, )

Sets text_direction.

fn fit(self: RenderHandle<Self>, app: &App) -> StackFit

How to size the non-positioned children in the stack.

fn set_fit(self: RenderHandle<Self>, app: &mut App, value: StackFit)

Sets fit.

fn clip_behavior(self: RenderHandle<Self>, app: &App) -> Clip

How to clip the children that overflow the stack.

fn set_clip_behavior(self: RenderHandle<Self>, app: &mut App, value: Clip)

Sets clip_behavior.

fn compute_min_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

The stack’s minimum intrinsic width: the widest non-positioned child’s.

fn compute_max_intrinsic_width( self: RenderHandle<Self>, app: &mut App, height: f64, ) -> f64

The stack’s maximum intrinsic width: the widest non-positioned child’s.

fn compute_min_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

The stack’s minimum intrinsic height: the tallest non-positioned child’s.

fn compute_max_intrinsic_height( self: RenderHandle<Self>, app: &mut App, width: f64, ) -> f64

The stack’s maximum intrinsic height: the tallest non-positioned child’s.

fn compute_distance_to_actual_baseline( self: RenderHandle<Self>, app: &mut App, baseline: TextBaseline, ) -> Option<f64>

The stack’s baseline: the highest of its children’s.

fn compute_dry_baseline( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, baseline: TextBaseline, ) -> Option<f64>

The baseline the stack would have, measuring its children dry.

fn compute_dry_layout( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, ) -> Size

The size the stack would take, measuring its non-positioned children dry.

fn compute_size( self: RenderHandle<Self>, app: &mut App, constraints: BoxConstraints, layout_child: impl FnMut(&mut App, AnyRenderBox, BoxConstraints) -> Size, ) -> Size

Flutter’s _computeSize: measures the non-positioned children with layout_child and sizes the stack.

fn perform_layout(self: RenderHandle<Self>, app: &mut App)

The body of Flutter’s performLayout override.

fn paint( self: RenderHandle<Self>, app: &mut App, context: &mut PaintingContext, offset: Offset, )

The body of Flutter’s paint override.

fn dispose(self: RenderHandle<Self>, app: &mut App)

Flutter’s dispose: drop the clip layer handle, then super.dispose().