Table: add new features for Table and optimize code

[ziyoung]

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default-expand-all, expand-row-keys and expand-change event are supported.

• Closes [Feature Request] Optimizing Tree Table #14910 [Feature Request] [Feature Request] [Recommendation] Table table adds default expansion properties #14982 [Bug Report] row-style property is invalid at initialization time. #14993 Cross-column Width of [Feature Request] Table Cell #15358 [Bug Report] Don't remove child's DOM element in element-ui table with children #14998 The tree function of the [Bug Report] table component hides the child nodes of the tree when new nodes are added, as shown in the figure. #14933 [Bug Report] max-height attribute on table prevents new rows from being added #15371
• Related pr Table:Fix hides the child nodes of the tree when new nodes are added … #14973 Table: fix remove nested data not re-render element #15002

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[ziyoung]

TODO:

• fix max-height bug [Bug Report] After max-height is used to get the data, the height of the table cannot be automatically opened. #15485
• update doc for new feature
• add test cases for new feature
• allow modifying lazy loading data
• improve performance

[ziyoung]

Table scroll bug #15732

额外补充一个 demo 链接：https://codepen.io/rockyf/pen/VOdbEW?editors=1010

[RockyF]

https://codepen.io/rockyf/pen/VOdbEW?editors=1010#0

[sheeyphone]

I got 100px height when I set 'el-table' height with height="100%" at version 2.9.1.
hope to fix soon, thanks~~

[lansezhaji]

在table组件使用calc高度失效，element2.6.0版本无此问题

[lansezhaji]

I got 100px height when I set 'el-table' height with height="100%" at version 2.9.1.
hope to fix soon, thanks~~

i find such code in this function:

function parseHeight(height) {
  if (typeof height === 'number') {
    return height;
  }
  if (typeof height === 'string') {
    if (/^\d+(?:px)?/.test(height)) {
      return parseInt(height, 10);
    }
    console.warn('[Element Warn][ElTable]invalid height and it will be ignored.');
  }
  return null;
}

when height is 100%, parseInt function will make some computed error !!

[438345494]

2.9.1滚动条无法出现，2.8.2无此问题

[weizs]

补充一下问题，昨天评论说2.9.0及以下版本，tree table可以正常，2.9.1不正常，后面发现是因为我这边的数据同时有hasChildren和children，移除hasChildren后正常

官方文档这样描述

支持树类型的数据的显示。当 row 中包含 children 字段时，被视为树形数据。渲染树形数据时，必须要指定 row-key。支持子节点数据异步加载。设置 Table 的 lazy 属性为 true 与加载函数 load 。通过指定 row 中的 hasChildren 字段来指定哪些行是包含子节点。children 与 hasChildren 都可以通过 tree-props 配置。

我直接两个都加上了，算是我误读了吧

[ziyoung]

@weizs 懒加载的节点不能包含 children。文档没法细致到这个程度。后续添加一个 warn 警告吧。

[ziyoung]

2.9.1滚动条无法出现，2.8.2无此问题

是 bug，请提 issue。

[langlangbody]

"element-ui": "^2.9.1"

在使用 el-table 组件时 使用@select 方法 会报堆栈溢出的错误`

[sugarknight]

"element-ui": "^2.9.1" ,elTable组件 reserve-selection(保留之前选中的数据)有bug，2.8.2版本正常

[JasonHFeng]

@sugarknight +1，我这边同样有这个问题，只能回退2.8.2版本

[duanhe1986]

2.9.1滚动条无法出现，2.8.2无此问题

是bug，请提问。

Google Chrome 75.0.3770.80 Dropdown 下拉菜单、Select 选择器 出现抖动情况

[liuhuiwenllfy]

table高度问题还没有解决

[whxian]

"element-ui": "^2.9.1" ,elTable组件 reserve-selection(保留之前选中的数据)有bug，2.8.2版本正常

+1，我准备回退了……

[ruojianll]

数据加载后无法显示table，内容为空，退回到2.8.2ok

[tomatobybike]

数据加载后无法显示table，内容为空，退回到2.8.2ok

我也同样问题。2.9.1 开发环境没问题，打包后，表格无法显示 果断回退2.8.2

[lochstar]

Is there a reason we no longer allow a string value for table height? I've been using vh values in my project and haven't had any problems. Upgrading to 2.9.1 breaks this ability.

/edit
I see this was resolved in 2.10.0. Thanks!

[ziyoung]

Is there a reason we no longer allow a string value for table height? I've been using vh values in my project and haven't had any problems. Upgrading to 2.9.1 breaks this ability.

/edit
I see this was resolved in 2.10.0. Thanks!

fixed in #16013

[xiaogaofudao]

@ziyoung el-tree 有计划加入 virtualized 模式吗。用扁平结构实现树形菜单。优化 大数据卡顿问题

[dujj1996]

补充一下问题，昨天评论说2.9.0及以下版本，tree table可以正常，2.9.1不正常，后面发现是因为我这边的数据同时有hasChildren和children，可移除hasChildren后正常

官方文档这样描述

表中的惰性属性为true。支持树类型的数据的显示。当行中包含children分段时，被视为树形数据。渲染树形数据时，必须要指定row-key。通过指定行中的hasChildren分段来指定该行是包含子例程。children与hasChildren都可以通过tree-props配置。

我直接两个都加上了，算是我误读了吧

我的elementui版本2.9.1 可是树形表格children出不来 树形表格无效，只有最外层的父级

[dujj1996]

elementUI2.9.1版本 树形表格无效 只有第一层 children没出来