update custom theme docs (#7679)

* update custom theme docs

* update form docs

examples/docs/en-US/custom-theme.md

@@ -1,2 +1,92 @@
 ## Custom theme
-Under construction.
+Element uses BEM-styled CSS so that you can override styles easily. But if you need to replace styles at a large scale, e.g. change the theme color from blue to orange or green, maybe overriding them one by one is not a good idea, and this is where our theme customization tools kick in.
+
+### Changing theme color
+Under construction.
+
+### More customizations
+If you need more customization than just changing the theme color, please follow these steps:
+
+#### <strong>Install related tool</strong>
+First install the theme generator globally or locally. Local install is recommended because in this way, when others clone your project, npm will automatically install it for them.
+```shell
+npm i element-theme -g
+```
+
+Then install the chalk theme from npm or GitHub.
+```shell
+# from npm
+npm i element-theme-chalk -D
+
+# from GitHub
+npm i https://github.com/ElementUI/theme-chalk -D
+```
+
+#### <strong>Initialize variable file</strong>
+After successfully installing the above packages, a command named `et` is available in CLI (if the packages are installed locally, use `node_modules/.bin/et` instead). Run `-i` to initialize the variable file which outputs to `element-variables.scss` by default. And you can specify its output directory as you will.
+
+```shell
+et -i [custom output file]
+
+> ✔ Generator variables file
+```
+
+In `element-variables.scss` you can find all the variables we used to style Element and they are defined in SCSS format:
+```css
+$--color-primary: #409EFF !default;
+$--color-primary-light-1: mix($--color-white, $--color-primary, 10%); /* 53a8ff */
+$--color-primary-light-2: mix($--color-white, $--color-primary, 20%); /* 66b1ff */
+$--color-primary-light-3: mix($--color-white, $--color-primary, 30%); /* 79bbff */
+$--color-primary-light-4: mix($--color-white, $--color-primary, 40%); /* 8cc5ff */
+$--color-primary-light-5: mix($--color-white, $--color-primary, 50%); /* a0cfff */
+$--color-primary-light-6: mix($--color-white, $--color-primary, 60%); /* b3d8ff */
+$--color-primary-light-7: mix($--color-white, $--color-primary, 70%); /* c6e2ff */
+$--color-primary-light-8: mix($--color-white, $--color-primary, 80%); /* d9ecff */
+$--color-primary-light-9: mix($--color-white, $--color-primary, 90%); /* ecf5ff */
+
+$--color-success: #67c23a !default;
+$--color-warning: #eb9e05 !default;
+$--color-danger: #fa5555 !default;
+$--color-info: #878d99 !default;
+```
+
+#### <strong>Modify variables</strong>
+Just edit `element-variables.scss`, e.g. changing the theme color to red:
+```CSS
+$--color-primary: red;
+```
+
+#### <strong>Build theme</strong>
+After saving the variable file, use `et` to build your theme. You can activate `watch` mode by adding a parameter `-w`. And if you customized the variable file's output, you need to add a parameter `-c` and variable file's name:
+```shell
+et
+
+> ✔ build theme font
+> ✔ build element theme
+```
+
+#### <strong>Import custom theme</strong>
+By default the build theme file is placed inside `./theme`. You can specify its output directory with parameter `-o`. Importing your own theme is just like importing the default theme, only this time you import the file you just built:
+
+```javascript
+import '../theme/index.css'
+import ElementUI from 'element-ui'
+import Vue from 'vue'
+
+Vue.use(ElementUI)
+```
+
+#### <strong>Import component theme on demand</strong>
+If you are using `babel-plugin-component` for on-demand import, just modify `.babelrc` and specify `styleLibraryName` to the path where your custom theme is located relative to `.babelrc`. Note that `~` is required:
+```json
+{
+  "plugins": [["component", [
+    {
+      "libraryName": "element-ui",
+      "styleLibraryName": "~theme"
+    }
+  ]]]
+}
+```
+
+If you are unfamiliar with `babel-plugin-component`, please refer to <a href="./#/en-US/component/quickstart">Quick Start</a>. For more details, check out the [project repository](https://github.com/ElementUI/element-theme) of `element-theme`.

examples/docs/en-US/form.md

@@ -5,17 +5,15 @@
         if (!value) {
           return callback(new Error('Please input the age'));
         }
-        setTimeout(() => {
-          if (!Number.isInteger(value)) {
-            callback(new Error('Please input digits'));
+        if (!Number.isInteger(value)) {
+          callback(new Error('Please input digits'));
+        } else {
+          if (value < 18) {
+            callback(new Error('Age must be greater than 18'));
           } else {
-            if (value < 18) {
-              callback(new Error('Age must be greater than 18'));
-            } else {
-              callback();
-            }
+            callback();
           }
-        }, 1000);
+        }
       };
       var validatePass = (rule, value, callback) => {
         if (value === '') {
@@ -548,17 +546,15 @@ This example shows how to customize your own validation rules to finish a two-fa
         if (!value) {
           return callback(new Error('Please input the age'));
         }
-        setTimeout(() => {
-          if (!Number.isInteger(value)) {
-            callback(new Error('Please input digits'));
+        if (!Number.isInteger(value)) {
+          callback(new Error('Please input digits'));
+        } else {
+          if (value < 18) {
+            callback(new Error('Age must be greater than 18'));
           } else {
-            if (value < 18) {
-              callback(new Error('Age must be greater than 18'));
-            } else {
-              callback();
-            }
+            callback();
           }
-        }, 1000);
+        }
       };
       var validatePass = (rule, value, callback) => {
         if (value === '') {

examples/docs/zh-CN/custom-theme.md

@@ -1,2 +1,92 @@
 ## 自定义主题
+Element 默认提供一套主题，CSS 命名采用 BEM 的风格方便使用者覆盖样式。如果你想完全替换主题色或者部分样式，可以使用下面的方法。
+
+### 仅替换主题色
 整理中。
+
+### 深层次的定制
+如果仅仅改变主题色不能满足你的需求，请按以下步骤进行更深层次的主题定制：
+
+#### <strong>安装工具</strong>
+首先安装「主题生成工具」，可以全局安装或者安装在当前项目下，推荐安装在项目里，方便别人 clone 项目时能直接安装依赖并启动，这里以全局安装做演示。
+```shell
+npm i element-theme -g
+```
+
+安装白垩主题，可以从 npm 安装或者从 GitHub 拉取最新代码。
+```shell
+# 从 npm
+npm i element-theme-chalk -D
+
+# 从 GitHub
+npm i https://github.com/ElementUI/theme-chalk -D
+```
+
+#### <strong>初始化变量文件</strong>
+主题生成工具安装成功后，如果全局安装可以在命令行里通过 `et` 调用工具，如果安装在当前目录下，需要通过 `node_modules/.bin/et` 访问到命令。执行 `-i` 初始化变量文件。默认输出到 `element-variables.scss`，当然你可以传参数指定文件输出目录。
+
+```shell
+et -i [可以自定义变量文件]
+
+> ✔ Generator variables file
+```
+
+如果使用默认配置，执行后当前目录会有一个 `element-variables.scss` 文件。内部包含了主题所用到的所有变量，它们使用 SCSS 的格式定义。大致结构如下：
+```css
+$--color-primary: #409EFF !default;
+$--color-primary-light-1: mix($--color-white, $--color-primary, 10%); /* 53a8ff */
+$--color-primary-light-2: mix($--color-white, $--color-primary, 20%); /* 66b1ff */
+$--color-primary-light-3: mix($--color-white, $--color-primary, 30%); /* 79bbff */
+$--color-primary-light-4: mix($--color-white, $--color-primary, 40%); /* 8cc5ff */
+$--color-primary-light-5: mix($--color-white, $--color-primary, 50%); /* a0cfff */
+$--color-primary-light-6: mix($--color-white, $--color-primary, 60%); /* b3d8ff */
+$--color-primary-light-7: mix($--color-white, $--color-primary, 70%); /* c6e2ff */
+$--color-primary-light-8: mix($--color-white, $--color-primary, 80%); /* d9ecff */
+$--color-primary-light-9: mix($--color-white, $--color-primary, 90%); /* ecf5ff */
+
+$--color-success: #67c23a !default;
+$--color-warning: #eb9e05 !default;
+$--color-danger: #fa5555 !default;
+$--color-info: #878d99 !default;
+```
+
+#### <strong>修改变量</strong>
+直接编辑 `element-variables.scss` 文件，例如修改主题色为红色。
+```CSS
+$--color-primary: red;
+```
+
+#### <strong>编译主题</strong>
+保存文件后，到命令行里执行 `et` 编译主题，如果你想启用 `watch` 模式，实时编译主题，增加 `-w` 参数；如果你在初始化时指定了自定义变量文件，则需要增加 `-c` 参数，并带上你的变量文件名
+```shell
+et
+
+> ✔ build theme font
+> ✔ build element theme
+```
+
+#### <strong>引入自定义主题</strong>
+默认情况下编译的主题目录是放在 `./theme` 下，你可以通过 `-o` 参数指定打包目录。像引入默认主题一样，在代码里直接引用 `theme/index.css` 文件即可。
+
+```javascript
+import '../theme/index.css'
+import ElementUI from 'element-ui'
+import Vue from 'vue'
+
+Vue.use(ElementUI)
+```
+
+#### <strong>搭配插件按需引入组件主题</strong>
+如果是搭配 `babel-plugin-component` 一起使用，只需要修改 `.babelrc` 的配置，指定 `styleLibraryName` 路径为自定义主题相对于 `.babelrc` 的路径，注意要加 `~`。
+```json
+{
+  "plugins": [["component", [
+    {
+      "libraryName": "element-ui",
+      "styleLibraryName": "~theme"
+    }
+  ]]]
+}
+```
+
+如果不清楚 `babel-plugin-component` 是什么，请阅读 <a href="./#/zh-CN/component/quickstart">快速上手</a> 一节。更多 `element-theme` 用法请参考[项目仓库](https://github.com/ElementUI/element-theme)。

examples/docs/zh-CN/form.md

@@ -5,17 +5,15 @@
         if (!value) {
           return callback(new Error('年龄不能为空'));
         }
-        setTimeout(() => {
-          if (!Number.isInteger(value)) {
-            callback(new Error('请输入数字值'));
+        if (!Number.isInteger(value)) {
+          callback(new Error('请输入数字值'));
+        } else {
+          if (value < 18) {
+            callback(new Error('必须年满18岁'));
           } else {
-            if (value < 18) {
-              callback(new Error('必须年满18岁'));
-            } else {
-              callback();
-            }
+            callback();
           }
-        }, 1000);
+        }
       };
       var validatePass = (rule, value, callback) => {
         if (value === '') {
@@ -539,17 +537,15 @@
         if (!value) {
           return callback(new Error('年龄不能为空'));
         }
-        setTimeout(() => {
-          if (!Number.isInteger(value)) {
-            callback(new Error('请输入数字值'));
+        if (!Number.isInteger(value)) {
+          callback(new Error('请输入数字值'));
+        } else {
+          if (value < 18) {
+            callback(new Error('必须年满18岁'));
           } else {
-            if (value < 18) {
-              callback(new Error('必须年满18岁'));
-            } else {
-              callback();
-            }
+            callback();
           }
-        }, 1000);
+        }
       };
       var validatePass = (rule, value, callback) => {
         if (value === '') {

packages/select/src/select.vue

@@ -544,7 +544,7 @@
 
       resetInputHeight() {
         this.$nextTick(() => {
-          if (!this.$refs.reference) return;
+          if (!this.$refs.reference || !this.$refs.tags) return;
           let inputChildNodes = this.$refs.reference.$el.childNodes;
           let input = [].filter.call(inputChildNodes, item => item.tagName === 'INPUT')[0];
           input.style.height = this.selected.length === 0 && this.size === 'mini'