Ubuntu18.04为vim安装自动补全插件YCM

首先需要安装：

sudo apt-get install vim
sudo apt-get install git
sudo apt-get install subversion
sudo apt-get install python3 python3-dev 
sudo apt-get install gcc
sudo apt-get install cmake
sudo apt-get install clang

安装vim的插件管理工具Vundle：

git clone https://github.com/VundleVim/Vundle.vim.git ~/.vim/bundle/Vundle.vim

添加配置文件：

set nocompatible              " be iMproved, required
filetype off                  " required
 
set rtp+=~/.vim/bundle/Vundle.vim
call vundle#begin()
Plugin 'VundleVim/Vundle.vim'
 
Plugin 'Valloric/YouCompleteMe'
 
call vundle#end()            " required
filetype plugin indent on    " required

安装YCM：

#下载YouCompleteMe源码
git clone https://github.com/Valloric/YouCompleteMe.git ~/.vim/bundle/YouCompleteMe
cd ~/.vim/bundle/YouCompleteMe/ 
git submodule update --init --recursive
cd ~/.vim/bundle/YouCompleteMe  
./install.py --clang-completer --system-libclang

自动化安装

sudo apt-get install vim-addon-manager 
sudo apt-get install vim-youcompleteme
vim-addons install youcompleteme

修改配置文件～/.vim/bundle/YouCompleteMe/third_party/ycmd/examples/.ycm_extra_conf.py:
在flag中添加：

'-isystem',
 '/usr/include',
 '-isystem',
 '/usr/include/c++/7',
 '-isystem',
 '/usr/include/clang/6.0/include',
 '-isystem',
 '/usr/include/x86_64-linux-gnu/sys',

并将这个文件复制到～/
修改～/.vimrc，末尾添加:

" 自动补全配置
set completeopt=longest,menu    "让Vim的补全菜单行为与一般IDE一致(参考VimTip1228)
autocmd InsertLeave * if pumvisible() == 0|pclose|endif "离开插入模式后自动关闭预览窗口
inoremap         pumvisible() ? "\<C-y>" : "\<CR>"    "回车即选中当前项
"上下左右键的行为 会显示其他信息
inoremap       pumvisible() ? "\<C-n>" : "\<Down>"
inoremap         pumvisible() ? "\<C-p>" : "\<Up>"
inoremap   pumvisible() ? "\<PageDown>\<C-p>\<C-n>" : "\<PageDown>"
inoremap     pumvisible() ? "\<PageUp>\<C-p>\<C-n>" : "\<PageUp>"

"youcompleteme  默认tab  s-tab 和自动补全冲突
"let g:ycm_key_list_select_completion=['']
let g:ycm_key_list_select_completion = ['']
"let g:ycm_key_list_previous_completion=['']
let g:ycm_key_list_previous_completion = ['']
let g:ycm_confirm_extra_conf=0
let g:ycm_global_ycm_extra_conf='/home/txz/.ycm_extra_conf.py'
let g:ycm_collect_identifiers_from_tags_files=1 " 开启 YCM 基于标签引擎
let g:ycm_min_num_of_chars_for_completion=2 " 从第2个键入字符就开始罗列匹配项
let g:ycm_cache_omnifunc=0  " 禁止缓存匹配项,每次都重新生成匹配项
let g:ycm_seed_identifiers_with_syntax=1    " 语法关键字补全
nnoremap <F5> :YcmForceCompileAndDiagnostics<CR>    "force recomile with syntastic
"nnoremap <leader>lo :lopen<CR> "open locationlist
"nnoremap <leader>lc :lclose<CR>    "close locationlist
inoremap  

"在注释输入中也能补全
let g:ycm_complete_in_comments = 1
"在字符串输入中也能补全
let g:ycm_complete_in_strings = 1
"注释和字符串中的文字也会被收入补全
let g:ycm_collect_identifiers_from_comments_and_strings = 0
nnoremap <leader>jd :YcmCompleter GoToDefinitionElseDeclaration<CR> " 跳转到定义处

这时就可以自动提示和代码补全了，但是奇怪的是创建一个新文件时无法提示stl的方法，第二次打开就可以了;