Module layout 

Layout utilities

For documentation of layout resolution, see the Layout trait.

Size units are physical (real) pixels. This applies to most of KAS.

Data types

SizeRules is the “heart” of widget layout, used to specify a widget’s size requirements. It provides various methods to compute derived rules and SizeRules::solve_seq, the “muscle” of the layout engine.

AxisInfo, Margins and Stretch are auxilliary data types.

Solvers

The RulesSolver and RulesSetter traits define interfaces for layout engines:

• SingleSolver and SingleSetter are trivial implementations for single-child parents
• RowSolver and RowSetter set out a row or column of children. These are parametrised over S: RowStorage allowing both efficient operation on a small fixed number of children with FixedRowStorage and operation on a over a Vec with DynRowStorage.
• GridSolver and GridSetter set out children assigned to grid cells with optional cell-spans. This is the most powerful and flexible layout engine.

RowPositionSolver may be used with widgets set out by RowSetter to quickly locate children from a coord or rect.

Structs

AlignHints

Partial alignment information provided by the parent

AlignPair

Provides alignment information on both axes along with ideal size

AxisInfo

Information on which axis is being resized

DynGridStorage

Variable-length grid storage

DynRowStorage

Variable-length row storage

FixedGridStorage

Fixed-length grid storage

FixedRowStorage

Fixed-length row storage

FrameRules

Frame size rules

FrameStorage

Layout storage for frame

GridCellInfo

Grid cell index and span information

GridDimensions

Grid dimensions

GridSetter

A RulesSetter for grids supporting cell-spans

GridSolver

A RulesSolver for grids supporting cell-spans

LogicalSize

Logical (pre-scaling) pixel size

Margins

Margin sizes

PackStorage

Layout storage for pack

PixmapScaling

Control over scaling

RowPositionSolver

Allows efficient implementations of draw / event handlers based on the layout representation.

RowSetter

A RulesSetter for rows (and, without loss of generality, for columns).

RowSolver

A RulesSolver for rows (and, without loss of generality, for columns).

SingleSetter

RulesSetter implementation for a fixed single-child layout

SingleSolver

RulesSolver implementation for a fixed single-child layout

SizeRules

Widget sizing information

SolveCache

Size solver

Enums

Align

Alignment of contents

Stretch

Priority for stretching widgets beyond ideal size

Traits

DefaultWithLen

Bound on GridSolver type parameters

GridStorage

Requirements of grid solver storage type

RowStorage

Requirements of row solver storage type

RowTemp

Temporary storage type.

RulesSetter

Resolves a RulesSolver solution for each child

RulesSolver

A SizeRules solver for layouts

Functions

solve_size_rules

Solve size rules for a widget