React Native Flexbox & CSS3 Flexbox Grid Layout
flex container & flex item
采用 Flex 布局的元素,称为 Flex 容器(flex container),简称"容器"。它的所有子元素自动成为容器成员,称为 Flex 项目(flex item),简称"项目"。
main axis & cross axis
容器默认存在两根轴:水平的主轴(main axis)和垂直的交叉轴(cross axis)。
- 主轴的开始位置(与边框的交叉点)叫做main start,结束位置叫做main end;
- 交叉轴的开始位置叫做cross start,结束位置叫做cross end。
- 项目默认沿主轴排列。单个项目占据的主轴空间叫做main size,占据的交叉轴空间叫做cross size。
flex container's properties
容器的 6个属性
- flex-direction
- flex-wrap
- flex-flow
- justify-content
- align-items
- align-content
flex-direction
flex-direction: row | row-reverse | column | column-reverse;
& default value(row)
flex-wrap
flex-wrap: nowrap | wrap | wrap-reverse;
& default value(nowrap)
https://codepen.io/team/css-tricks/pen/1ea1ef35d942d0041b0467b4d39888d3
flex-flow
flex-flow
is shorthand flex-direction
& flex-wrap
flex-flow: <‘flex-direction’> || <‘flex-wrap’>
& default value(row nowrap)
justify-content
justify-content: flex-start | flex-end | center | space-between | space-around | space-evenly;
& default value(flex-start)
align-items
align-items: stretch | flex-start | flex-end | center | baseline;
& default value(stretch)
align-content
align-content: flex-start | flex-end | center | space-between | space-around | stretch;
& default value(flex-start)
flex item's properties
项目的 6个属性
- order
- flex-grow
- flex-shrink
- flex-basis
- flex
- align-self
order
order: <integer>;
& default value(0)
flex-grow
flex-grow: <number>;
& default value(0)
flex-shrink
flex-shrink: <number>;
& default value(1)
- 负数无效
flex-basis
flex-basis: <length> | auto;
& default value(auto)
flex
flex is shorthand for
flex-grow
& flex-shrink
& flex-basis
flex: none | [ <'flex-grow'> <'flex-shrink'>? || <'flex-basis'> ]
& default value(0 1 auto)
align-self
align-self: auto | flex-start | flex-end | center | baseline | stretch;
& default value(auto)
align-self 属性允许单个项目有与其他项目不一样的对齐方式,可覆盖align-items属性。默认值为auto,表示继承父元素的align-items属性,如果没有父元素,则等同于stretch