The first lesson explaining the basics of WeChat mini program development

1. 9*9 multiplication table

test.wxml

<view class=&#39;con&#39; wx:for="{{[1,2,3,4,5,6,7,8,9]}}" wx:for-item="i">
    <view style=&#39;display:inline-block;width:45px&#39; wx:for="{{[1,2,3,4,5,6,7,8,9]}}" wx:for-item="j">
        <view wx:if="{{j<=i}}">
            {{i}}*{{j}}={{i*j}}
        </view>
    </view>
</view>

test.wxss

.con{
    font-size:8px;
}

Running result:

2. Window scrolling

XX.wxml

<scroll-view class=&#39;aa&#39; scroll-y="ture">
<view class="a">
1
</view>
<view class="b">
2
</view>
<view class="c">
3
</view>
</scroll-view>

XX.wxss

/* pages/news/news.wxss */

.aa{
  width:200px;
  height: 100px; 
}
.a{
  height: 200rpx;
  background-color: red;
}
.b{
  height: 200rpx;
  background-color: gold;
}
.c{
  height: 200rpx;
  background-color: green;
}

This example is vertical scrolling

a fixed height and set the height through WXSS.

XX.wxml

<swiper indicator-dots="ture" autoplay="ture" interval="1000" duration="1000">
<block wx:for="{{imgUrls}}">
  <swiper-item>
    <image src=&#39;{{item}}&#39;></image>
  </swiper-item>
</block>
</swiper>

XX.js

imgUrls:[
      "../image/1.png",
      "../image/2.png",
      "../image/3.png"
    ],

Related knowledge points

注意：其中只可放置<swiper-item/> 组件，其他节点会被自动删除。

四、弹性布局

父元素设置display：flex

相关知识点：

Flex 是 Flexible Box 的缩写，意为"弹性布局"，用来为盒状模型提供最大的灵活性。

任何一个容器都可以指定为 Flex 布局。

.box{
  display: flex;}

Copy after login

行内元素也可以使用 Flex 布局。

.box{
  display: inline-flex;}

Copy after login

Webkit 内核的浏览器，必须加上-webkit前缀。

.box{
  display: -webkit-flex; /* Safari */
  display: flex;}

Copy after login

注意，设为 Flex 布局以后，子元素的float、clear和vertical-align属性将失效。

二、基本概念

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"。

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。

三、容器的属性

以下6个属性设置在容器上。

• flex-direction

• flex-wrap

• flex-flow

• justify-content

• align-items

• align-content

3.1 flex-direction属性

flex-direction属性决定主轴的方向（即项目的排列方向）。

.box {
  flex-direction: row | row-reverse | column | column-reverse;}

Copy after login

它可能有4个值。

• row（默认值）：主轴为水平方向，起点在左端。

• row-reverse：主轴为水平方向，起点在右端。

• column：主轴为垂直方向，起点在上沿。

• column-reverse：主轴为垂直方向，起点在下沿。

3.2 flex-wrap属性

默认情况下，项目都排在一条线（又称"轴线"）上。flex-wrap属性定义，如果一条轴线排不下，如何换行。

.box{
  flex-wrap: nowrap | wrap | wrap-reverse;}

Copy after login

它可能取三个值。

（1）nowrap（默认）：不换行。

（2）wrap：换行，第一行在上方。

（3）wrap-reverse：换行，第一行在下方。

3.3 flex-flow

flex-flow属性是flex-direction属性和flex-wrap属性的简写形式，默认值为row nowrap。

.box {
  flex-flow: <flex-direction> || <flex-wrap>;}

Copy after login

3.4 justify-content属性

justify-content属性定义了项目在主轴上的对齐方式。

.box {
  justify-content: flex-start | flex-end | center | space-between | space-around;}

Copy after login

它可能取5个值，具体对齐方式与轴的方向有关。下面假设主轴为从左到右。

• flex-start（默认值）：左对齐

• flex-end：右对齐

• center： 居中

• space-between：两端对齐，项目之间的间隔都相等。

• space-around：每个项目两侧的间隔相等。所以，项目之间的间隔比项目与边框的间隔大一倍。

3.5 align-items属性

align-items属性定义项目在交叉轴上如何对齐。

.box {
  align-items: flex-start | flex-end | center | baseline | stretch;}

Copy after login

它可能取5个值。具体的对齐方式与交叉轴的方向有关，下面假设交叉轴从上到下。

• flex-start：交叉轴的起点对齐。

• flex-end：交叉轴的终点对齐。

• center：交叉轴的中点对齐。

• baseline: 项目的第一行文字的基线对齐。

• stretch（默认值）：如果项目未设置高度或设为auto，将占满整个容器的高度。

3.6 align-content属性

align-content属性定义了多根轴线的对齐方式。如果项目只有一根轴线，该属性不起作用。

.box {
  align-content: flex-start | flex-end | center | space-between | space-around | stretch;}

Copy after login

该属性可能取6个值。

• flex-start：与交叉轴的起点对齐。

• flex-end：与交叉轴的终点对齐。

• center：与交叉轴的中点对齐。

• space-between：与交叉轴两端对齐，轴线之间的间隔平均分布。

• space-around：每根轴线两侧的间隔都相等。所以，轴线之间的间隔比轴线与边框的间隔大一倍。

• stretch（默认值）：轴线占满整个交叉轴。

四、项目的属性

以下6个属性设置在项目上。

• <span style="font-size:16px;">order</span>

• <span style="font-size:16px;">flex-grow</span>

• <span style="font-size:16px;">flex-shrink</span>

• <span style="font-size:16px;">flex-basis</span>

• <span style="font-size:16px;">flex</span>

• <span style="font-size:16px;">align-self</span>

4.1 order属性

order属性定义项目的排列顺序。数值越小，排列越靠前，默认为0。

.item {
  order: <integer>;}

Copy after login

4.2 flex-grow属性

flex-grow属性定义项目的放大比例，默认为0，即如果存在剩余空间，也不放大。

.item {
  flex-grow: <number>; /* default 0 */}

Copy after login

如果所有项目的flex-grow属性都为1，则它们将等分剩余空间（如果有的话）。如果一个项目的flex-grow属性为2，其他项目都为1，则前者占据的剩余空间将比其他项多一倍。

4.3 flex-shrink属性

flex-shrink属性定义了项目的缩小比例，默认为1，即如果空间不足，该项目将缩小。

.item {
  flex-shrink: <number>; /* default 1 */}

Copy after login

如果所有项目的flex-shrink属性都为1，当空间不足时，都将等比例缩小。如果一个项目的flex-shrink属性为0，其他项目都为1，则空间不足时，前者不缩小。

负值对该属性无效。

4.4 flex-basis属性

flex-basis属性定义了在分配多余空间之前，项目占据的主轴空间（main size）。浏览器根据这个属性，计算主轴是否有多余空间。它的默认值为auto，即项目的本来大小。

.item {
  flex-basis: <length> | auto; /* default auto */}

Copy after login

它可以设为跟width或height属性一样的值（比如350px），则项目将占据固定空间。

4.5 flex属性

flex属性是flex-grow, flex-shrink 和 flex-basis的简写，默认值为0 1 auto。后两个属性可选。

.item {
  flex: none | [ <&#39;flex-grow&#39;> <&#39;flex-shrink&#39;>? || <&#39;flex-basis&#39;> ]}

Copy after login

该属性有两个快捷值：auto (1 1 auto) 和 none (0 0 auto)。

建议优先使用这个属性，而不是单独写三个分离的属性，因为浏览器会推算相关值。

4.6 align-self属性

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。

.item {
  align-self: auto | flex-start | flex-end | center | baseline | stretch;}

Copy after login

This attribute may take 6 values. Except for auto, the others are exactly the same as the align-items attribute.

This article explains in detail the basics of WeChat applet development. For more related content, please pay attention to the PHP Chinese website.

Related recommendations:

How to perform 2D conversion through CSS3

Detailed explanation of JavaScript variables and scope

Detailed explanation of $.ajax() method parameters

The above is the detailed content of The first lesson explaining the basics of WeChat mini program development. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Show More

Hot Article

How to fix KB5055523 fails to install in Windows 11?

3 weeks ago By DDD

How to fix KB5055518 fails to install in Windows 10?

3 weeks ago By DDD

Strength Levels for Every Enemy & Monster in R.E.P.O.

3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Roblox: Dead Rails - How To Tame Wolves

3 weeks ago By DDD

Blue Prince: How To Get To The Basement

3 weeks ago By DDD

Show More

Hot Tools

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Show More

Hot Topics

Java Tutorial

1655

14

CakePHP Tutorial

1413

52

Laravel Tutorial

1306

25

PHP Tutorial

1252

29

C# Tutorial

1226

24

Show More

Related knowledge

Is the company's security software causing the application to fail to run? How to troubleshoot and solve it? Apr 19, 2025 pm 04:51 PM

Troubleshooting and solutions to the company's security software that causes some applications to not function properly. Many companies will deploy security software in order to ensure internal network security. ...

What is the difference between H5 page production and WeChat applets Apr 05, 2025 pm 11:51 PM

H5 is more flexible and customizable, but requires skilled technology; mini programs are quick to get started and easy to maintain, but are limited by the WeChat framework.

How to solve the problem of JS resource caching in enterprise WeChat? Apr 04, 2025 pm 05:06 PM

Discussion on the JS resource caching issue of Enterprise WeChat. When upgrading project functions, some users often encounter situations where they fail to successfully upgrade, especially in the enterprise...

Ouyi Exchange app domestic download tutorial Mar 21, 2025 pm 05:42 PM

This article provides a detailed guide to safe download of Ouyi OKX App in China. Due to restrictions on domestic app stores, users are advised to download the App through the official website of Ouyi OKX, or use the QR code provided by the official website to scan and download. During the download process, be sure to verify the official website address, check the application permissions, perform a security scan after installation, and enable two-factor verification. During use, please abide by local laws and regulations, use a safe network environment, protect account security, be vigilant against fraud, and invest rationally. This article is for reference only and does not constitute investment advice. Digital asset transactions are at your own risk.

The difference between H5 and mini-programs and APPs Apr 06, 2025 am 10:42 AM

H5. The main difference between mini programs and APP is: technical architecture: H5 is based on web technology, and mini programs and APP are independent applications. Experience and functions: H5 is light and easy to use, with limited functions; mini programs are lightweight and have good interactiveness; APPs are powerful and have smooth experience. Compatibility: H5 is cross-platform compatible, applets and APPs are restricted by the platform. Development cost: H5 has low development cost, medium mini programs, and highest APP. Applicable scenarios: H5 is suitable for information display, applets are suitable for lightweight applications, and APPs are suitable for complex functions.

What should I do if the company's security software conflicts with applications? How to troubleshoot HUES security software causes common software to fail to open? Apr 01, 2025 pm 10:48 PM

Compatibility issues and troubleshooting methods for company security software and application. Many companies will install security software in order to ensure intranet security. However, security software sometimes...

How to choose H5 and applets Apr 06, 2025 am 10:51 AM

The choice of H5 and applet depends on the requirements. For applications with cross-platform, rapid development and high scalability, choose H5; for applications with native experience, rich functions and platform dependencies, choose applets.

What are the development tools for H5 and mini program? Apr 06, 2025 am 09:54 AM

H5 development tools recommendations: VSCode, WebStorm, Atom, Brackets, Sublime Text; Mini Program Development Tools: WeChat Developer Tools, Alipay Mini Program Developer Tools, Baidu Smart Mini Program IDE, Toutiao Mini Program Developer Tools, Taro.

See all articles