Подход к проектированию API
Nós aprendemos bastante como o Material-UI é usado e o refatoramento da v1 permitiu-nos repensar completamente o componente de API.
API design is hard because you can make it seem simple but it's actually deceptively complex, or make it actually simple but seem complex.
As Sebastian Markbage pointed out, no abstraction is superior to wrong abstractions. We are providing low-level components to maximize composition capabilities.
Composition
You may have noticed some inconsistency in the API regarding composing components. To provide some transparency, we have been using the following rules when designing the API:
- Using the
children
property is the idiomatic way to do composition with React. - Sometimes we only need limited child composition, for instance when we don't need to allow child order permutations. In this case, providing explicit properties makes the implementation simpler and more performant; for example, the
Tab
takes anicon
and alabel
property. - API consistency matters.
Rules
Aside from the above composition trade-off, we enforce the following rules:
Spread
Props supplied to a component which are not explicitly documented are spread to the root element; for instance, the className
prop is applied to the root.
Now, let's say you want to disable the ripples on the MenuItem
. You can take advantage of the spread behavior:
<MenuItem disableRipple />
The disableRipple
property will flow this way: MenuItem
> ListItem
> ButtonBase
.
Native properties
We avoid documenting native properties supported by the DOM like className
.
CSS Classes
All components accept a classes
prop to customize the styles. The classes design answers two constraints: to make the classes structure as simple as possible, while sufficient to implement the Material Design specification.
- The class applied to the root element is always called
root
. - All the default styles are grouped in a single class.
- The classes applied to non-root elements are prefixed with the name of the element, e.g.
paperWidthXs
in the Dialog component. - The variants applied by a boolean property aren't prefixed, e.g. the
rounded
class applied by therounded
property. - The variants applied by an enum property are prefixed, e.g. the
colorPrimary
class applied by thecolor="primary"
property. - A variant has one level of specificity. The
color
andvariant
properties are considered a variant. The lower the style specificity is, the simpler it is to override. - We increase the specificity for a variant modifier. We increase the specificity for a variant modifier. It allows much more control at the cost of more boilerplate. Hopefully, it's also more intuitive.
const styles = {
root: {
color: green[600],
'&$checked': {
color: green[500],
},
},
checked: {},
};
Nested components
Nested components inside a component have:
- their own flattened properties when these are key to the top level component abstraction, for instance an
id
prop for theInput
component. - their own
xxxProps
property when users might need to tweak the internal render method's sub-components, for instance, exposing theinputProps
andInputProps
properties on components that useInput
internally. - their own
xxxComponent
property for performing component injection. - экземляр
window.HTMLDivElement
. This helps answer the question "How can I access the DOM element?"
Property naming
The name of a boolean property should be chosen based on the default value. For example, the disabled
attribute on an input element, if supplied, defaults to true
. This choice allows the shorthand notation:
-<Input enabled={false} />
+<Input disabled />
Управляемые компоненты
Большинство управляемых компонентов контролируются параметрами value
и onChange
, хотя комбинация open
/ onClose
/ onOpen
используется с отвечающим за отображение состоянием. Если же событий несколько, то мы ставим в начало существительное, а затем глагол, например: onPageChange
, onRowsChange
.
boolean vs enum
There are two options to design the API for the variations of a component: with a boolean; or with an enum. For example, let's take a button that has different types. Each option has its pros and cons:
Option 1 boolean:
type Props = { contained: boolean; fab: boolean; };
This API enables the shorthand notation:
<Button>
,<Button contained />
,<Button fab />
.Option 2 enum:
type Props = { variant: 'text' | 'contained' | 'fab'; }
This API is more verbose:
<Button>
,<Button variant="contained">
,<Button variant="fab">
.However it prevents an invalid combination from being used, bounds the number of properties exposed, and can easily support new values in the future.
The Material-UI components use a combination of the two approaches according to the following rules:
- A boolean is used when 2 possible values are required.
- An enum is used when > 2 possible values are required, or if there is the possibility that additional possible values may be required in the future.
Going back to the previous button example; since it requires 3 possible values, we use an enum.
Ref
The ref
is forwarded to the root element. This means that, without changing the rendered root element via the component
prop, it is forwarded to the outermost DOM element which the component renders. If you pass a different component via the component
prop, the ref will be attached to that component instead.
Словарь
- host element: DOM-нода в контексте
react-dom
, т.е. экземлярwindow.HTMLDivElement
. экземлярwindow.HTMLDivElement
. - host element: DOM-нода в контексте
react-dom
, т.е. экземлярwindow.HTMLDivElement
. - outermost: The first component when reading the component tree from top to bottom i.e. breadth-first search.
- root component: the outermost component that renders a host component.
- root element: the outermost element that renders a host component.