Module cursive::view[][src]

Base elements required to build views.

Views are the main building blocks of your UI.

A view can delegate part or all of its responsabilities to child views, forming a view tree. The root of this tree is a StackView handled directly by the Cursive element.

Layout

The layout phase is when the size and location of each view is computed.

Each view is given an area of the screen by the View::layout() method. With this, the view is free to plan its content, including calling View::layout() on its own children.

In order to determine how much space should be given each child, parents can use View::required_size() on them.

Contracts

When building new Views, you should respect these contracts:

  • By default, View::layout() should be called before any call to View::draw() with the same available size. The only exceptions is when both following conditions are met:

    • The available size has not changed since the last call to View::layout()
    • View::needs_relayout() returns false

    In this case, it is safe to omit the call to View::layout().

  • The value returned by required_size should be an actually viable size, no matter what the request is. This means calling View::layout() with a size returned by required_size is never an error.

Structs

Margins

Four values representing each direction.

ScrollBase

Provide scrolling functionalities to a view.

SizeCache

Cache around a one-dimensional layout result.

ViewPath

Represents a path to a single view in the layout.

Enums

Offset

Single-dimensional offset policy.

ScrollStrategy

Defines the scrolling behaviour on content or size change

Selector

Selects a single view (if any) in the tree.

SizeConstraint

Single-dimensional constraint on a view size.

Traits

AnyView

A view that can be downcasted to its concrete type.

Boxable

Makes a view wrappable in a BoxView.

Finder

Provides call_on<V: View> to views.

Identifiable

Makes a view wrappable in an IdView.

IntoBoxedView

Represents a type that can be made into a Box<View>.

Scrollable

Makes a view wrappable in a ScrollView.

View

Main trait defining a view behaviour.

ViewWrapper

Generic wrapper around a view.

Type Definitions

Position

Location of the view on screen