docs/css/margin-left.md
margin-left 属性 设置与元素相关联的盒子模型的左外边距。这个值可以为负值。
| Web | Android | iOS | HarmonyOS | HarmonyOS(Vapor) |
|---|---|---|---|---|
| 4.0 | 3.9 | 4.11 | 4.61 | 5.0 |
margin-left: <length> | <percentage> | auto;
| 名称 | 兼容性 | 描述 |
|---|---|---|
| auto | Web: 4.0; Android: 3.9; iOS: 4.11; HarmonyOS: 4.61; HarmonyOS(Vapor): 5.0 | auto 关键词表示在当前布局模式下，浏览器根据接收的左边距自动计算出外边距。如果有几组 margin-left 和 margin-right 设置为 auto，那么最后计算的空间分布，会根据 display，float，position 属性，自动生成以下几种情况： |
Value of display
Value of float
Value of position
Computed value of auto
Comment
inline, inline-block, inline-table
any
static or relative
0
Inline layout mode
block, inline, inline-block, block, table, inline-table, list-item, table-caption
any
static or relative
0, 除非margin-left和 margin-right 同时都设置为 auto。这样的话，元素就被设置为基于父元素居中。
Block layout mode
block, inline, inline-block, block, table, inline-table, list-item, table-caption
left or right
static or relative
0
Block layout mode (floating element)
any table-*, except table-caption
any
any
0
Internal table-* elements don't have margins, use border-spacing instead
any, except flex, inline-flex, or table-*
any
fixed or absolute
0, except if both margin-left and margin-right are set to auto. In this case, it is set to the value centering the border area inside the available width, if fixed.
Absolutely positioned layout mode
flex, inline-flex
any
any
在水平方向上有空余空间的情况下，空余的空间会被平均分给水平方向上写有 margin-left:auto 属性的元素的外边距
Flexbox layout mode |
0
注意
示例为hello uni-app x alpha分支，与最新HBuilderX Alpha版同步。与最新正式版同步的master分支示例另见 ::: preview https://hellouniappx.dcloud.net.cn/web/#/pages/CSS/margin/margin-left
appRedirect https://hellouniappx.dcloud.net.cn/appredirect.html?path=pages/CSS/margin/margin-left
示例
<template>
<!-- #ifdef APP -->
<scroll-view style="flex: 1">
<!-- #endif -->
<view style="flex-grow: 1;">
<text class="uni-tips">说明：左边是正常版本，右边是拍平版本</text>
<view>
<text>margin-left: 25px</text>
<view class="demo-box">
<view class="demo-container">
<view class="common red"></view>
<view class="common" style="margin-left: 25px;"></view>
<view class="common blue"></view>
</view>
<view class="demo-container">
<view class="common red"></view>
<view class="common" style="margin-left: 25px;" flatten></view>
<view class="common blue"></view>
</view>
</view>
</view>
<view>
<text>margin-left: 10%</text>
<view class="demo-box">
<view class="demo-container">
<view class="common red"></view>
<view class="common" style="margin-left: 10%;"></view>
<view class="common blue"></view>
</view>
<view class="demo-container">
<view class="common red"></view>
<view class="common" style="margin-left: 10%;" flatten></view>
<view class="common blue"></view>
</view>
</view>
</view>
<view class="uni-common-mt">
<text class="uni-title-text">scroll-view 组件</text>
</view>
<view>
<text class="uni-subtitle-text">margin-left: 10% 和 margin-left: 30px</text>
<view class="demo-box">
<view class="demo-container">
<view class="common red"></view>
<scroll-view class="common" style="margin-left: 10%;"></scroll-view>
<view class="common blue"></view>
</view>
<view class="demo-container">
<view class="common red"></view>
<scroll-view class="common" style="margin-left: 30px;"></scroll-view>
<view class="common blue"></view>
</view>
</view>
</view>
<view class="uni-common-mt">
<text class="uni-title-text">setProperty 设置与 getPropertyValue 获取 margin-left </text>
</view>
<view class="test-container">
<view class="test-item">
<text class="uni-subtitle-text">view 组件</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActual}}</text>
<view class="test-box">
<view class="common-view" style="background-color: red;"></view>
<view ref="viewRef" class="common-view test-view" :style="{ marginLeft: marginLeft }">
<text class="common-text">view</text>
</view>
<view class="common-view" style="background-color: blue;"></view>
</view>
</view>
<view class="test-item">
<text class="uni-subtitle-text">text 组件</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActualText}}</text>
<view class="test-box">
<text class="common-view common-text" style="background-color: red;">红色</text>
<text ref="textRef" class="common-view common-text test-text" :style="{ marginLeft: marginLeft }">text</text>
<text class="common-view common-text" style="background-color: blue;">蓝色</text>
</view>
</view>
<view class="test-item">
<text class="uni-subtitle-text">image 组件</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActualImage}}</text>
<view class="test-box">
<image class="common-image" style="background-color: red;" src="/static/test-image/logo.png"></image>
<image ref="imageRef" class="common-image test-image" :style="{ marginLeft: marginLeft }" src="/static/test-image/logo.png"></image>
<image class="common-image" style="background-color: blue;" src="/static/test-image/logo.png"></image>
</view>
</view>
</view>
<view class="test-container">
<view class="test-item">
<text class="uni-subtitle-text">view 组件拍平</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActualFlat}}</text>
<view class="test-box">
<view class="common-view" style="background-color: red;"></view>
<view ref="viewRefFlat" class="common-view test-view-flatten" :style="{ marginLeft: marginLeft }" flatten>
<text class="common-text">view</text>
</view>
<view class="common-view" style="background-color: blue;"></view>
</view>
</view>
<view class="test-item">
<text class="uni-subtitle-text">text 组件拍平</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActualTextFlat}}</text>
<view class="test-box">
<text class="common-view common-text" style="background-color: red;">红色</text>
<text ref="textRefFlat" class="common-view common-text test-text-flatten" :style="{ marginLeft: marginLeft }" flatten>text</text>
<text class="common-view common-text" style="background-color: blue;">蓝色</text>
</view>
</view>
<view class="test-item">
<text class="uni-subtitle-text">image 组件拍平</text>
<text class="uni-info">设置值: {{marginLeft}}</text>
<text class="uni-info">获取值: {{marginLeftActualImageFlat}}</text>
<view class="test-box">
<image class="common-image" style="background-color: red;" src="/static/test-image/logo.png"></image>
<image ref="imageRefFlat" class="common-image test-image-flatten" :style="{ marginLeft: marginLeft }" flatten src="/static/test-image/logo.png"></image>
<image class="common-image" style="background-color: blue;" src="/static/test-image/logo.png"></image>
</view>
</view>
</view>
<view class="uni-common-mt uni-common-mb">
<text class="uni-tips">第一个枚举值，'' (空字符串) - 空值情况</text>
<enum-data :items="marginLeftEnum" title="margin-left 枚举值" @change="radioChangeMarginLeft" :compact="true"></enum-data>
<input-data :defaultValue="marginLeft" title="margin-left 自定义值" type="text" @confirm="inputChangeMarginLeft"></input-data>
</view>
<view class="uni-common-mb">
<text>native-view组件: margin-left: 25px 和 10%</text>
<view class="demo-box">
<view class="demo-container">
<view class="common red"></view>
<native-view class="common" style="margin-left: 25px;"></native-view>
<view class="common blue"></view>
</view>
<view class="demo-container">
<view class="common red"></view>
<native-view class="common" style="margin-left: 10%;"></native-view>
<view class="common blue"></view>
</view>
</view>
</view>
</view>
<!-- #ifdef APP -->
</scroll-view>
<!-- #endif -->
</template>
<script setup lang="uts">
import { ItemType } from '@/components/enum-data/enum-data-types'
const marginLeft = ref('25px')
const marginLeftActual = ref('')
const marginLeftActualText = ref('')
const marginLeftActualImage = ref('')
const marginLeftActualFlat = ref('')
const marginLeftActualTextFlat = ref('')
const marginLeftActualImageFlat = ref('')
const viewRef = ref(null as UniElement | null)
const textRef = ref(null as UniTextElement | null)
const imageRef = ref(null as UniImageElement | null)
const viewRefFlat = ref(null as UniElement | null)
const textRefFlat = ref(null as UniTextElement | null)
const imageRefFlat = ref(null as UniImageElement | null)
const marginLeftEnum: ItemType[] = [
{ value: 0, name: '' },
{ value: 1, name: '0' },
{ value: 2, name: '0px' },
{ value: 3, name: '20px' },
{ value: 4, name: '0%' },
{ value: 5, name: '10%' },
{ value: 6, name: 'auto' }
]
const getPropertyValues = () => {
marginLeftActual.value = viewRef.value?.style.getPropertyValue('margin-left') ?? ''
marginLeftActualFlat.value = viewRefFlat.value?.style.getPropertyValue('margin-left') ?? ''
marginLeftActualText.value = textRef.value?.style.getPropertyValue('margin-left') ?? ''
marginLeftActualTextFlat.value = textRefFlat.value?.style.getPropertyValue('margin-left') ?? ''
marginLeftActualImage.value = imageRef.value?.style.getPropertyValue('margin-left') ?? ''
marginLeftActualImageFlat.value = imageRefFlat.value?.style.getPropertyValue('margin-left') ?? ''
}
const changeMarginLeft = (value: string) => {
marginLeft.value = value
viewRef.value?.style.setProperty('margin-left', value)
viewRefFlat.value?.style.setProperty('margin-left', value)
textRef.value?.style.setProperty('margin-left', value)
textRefFlat.value?.style.setProperty('margin-left', value)
imageRef.value?.style.setProperty('margin-left', value)
imageRefFlat.value?.style.setProperty('margin-left', value)
// 使用 nextTick 确保样式已应用后再获取值
nextTick(() => {
getPropertyValues()
})
}
const radioChangeMarginLeft = (index: number) => {
const selectedItem = marginLeftEnum.find((item): boolean => item.value === index)
if (selectedItem != null) {
changeMarginLeft(selectedItem.name)
}
}
const inputChangeMarginLeft = (value: string) => {
changeMarginLeft(value)
}
onReady(() => {
getPropertyValues()
})
defineExpose({
radioChangeMarginLeft
})
</script>
<style>
.demo-container {
flex: 1;
margin:0 10px;
height: 180px;
background-color: gray;
}
.demo-box {
flex-direction: row;
margin-top: 10px;
justify-content: space-around;
}
.common {
height: 50px;
background-color: green;
}
.red {
background-color: red;
}
.blue {
background-color: blue;
}
.green {
background-color: green;
}
.scroll-view-test {
height: 50px;
}
.common-view {
height: 30px;
background-color: green;
}
.common-text {
font-size: 12px;
color: white;
}
.common-image {
width: 30px;
height: 30px;
background-color: green;
}
.test-container {
flex-direction: row;
justify-content: space-between;
margin-top: 10px;
}
.test-item {
flex: 1;
margin: 0 5px;
}
.test-box {
width: 100%;
height: 100px;
background-color: gray;
}
</style>
:::