【原】iOS学习46之第三方CocoaPods的安装和使用（通用方法）
本文主要说明CocoaPods的安装步骤、使用说明和常见的报错即解决方法。
1. CocoaPods
1> CocoaPods简介
-
CocoaPods是一个用来帮助我们管理第三方依赖库的工具。
-
在开发iOS应用时，会经常使用第三方类库，比如SDWebImage、AFNetworking等等，手动的下载与添加类库非常麻烦，通过CocoaPods可以便捷的下载与管理第三方类库。
-
使用CocoaPods的目的是让我们能自动化的、集中的、直观的管理第三方开源库。
-
官方链接：https://cocoapods.org
- CocoaPods是用Ruby实现的，要想使用它首先需要有Ruby的环境，OS X系统默认支持Ruby运行，但是Ruby的默认源使用的是rubygems.org，国内访问这个网址时，如果无法FQ，则不能下载，解决方案是将其替换成可用的Ruby,比如淘宝，具体操作详见安装。
2> CocoaPods安装
- 第一步：查看自己电脑的Ruby环境，终端命令：gem sources -l
① 如果环境已经是taobao镜像了，此时不需要再进行环境修改
② 如果环境不是taobao镜像，将当前的镜像移除，终端命令：gem sources --remove https://rubygems.org/（当前的Ruby环境），接着下载taobao的镜像，终端命令：gem source -a https://gems.ruby-china.com/
- 第二步：安装CocoaPods
① 下载CocoaPods，终端命令：sudo gem install cocoapods （中间可能要输入管理员密码，不是明文，在你输入密码的时候不会提示）
这时候提示：
Fetching: i18n-0.7.0.gem (100%)
Successfully installed i18n-0.7.0
Fetching: thread_safe-0.3.5.gem (100%)
Successfully installed thread_safe-0.3.5
Fetching: tzinfo-1.2.2.gem (100%)
Successfully installed tzinfo-1.2.2
Fetching: minitest-5.9.0.gem (100%)
Successfully installed minitest-5.9.0
Fetching: concurrent-ruby-1.0.2.gem (100%)
Successfully installed concurrent-ruby-1.0.2
Fetching: activesupport-5.0.0.gem (100%)
ERROR: Error installing cocoapods:
activesupport requires Ruby version >= 2.2.2.
这个地方很坑，之前安装cocoapods一直是没有这个问题的，这里提示Ruby版本要大于或等于2.2.2
于是查看ruby版本
$ruby -v
ruby 2.0.0p648 (2015-12-16 revision 53162) [universal.x86_64-darwin15]
果然这里就要升级Ruby版本啦
查看目前的所有ruby版本：
$rvm list known
如果提示command not found 请先安装rvm
$curl -L get.rvm.io | bash -s stable
如果已安装会列出所有的ruby版本：
# MRI Rubies
[ruby-]1.8.6[-p420]
[ruby-]1.8.7[-head] # security released on head
[ruby-]1.9.1[-p431]
[ruby-]1.9.2[-p330]
[ruby-]1.9.3[-p551]
[ruby-]2.0.0[-p648]
[ruby-]2.1[.8]
[ruby-]2.2[.4]
[ruby-]2.3[.0]
[ruby-]2.2-head
ruby-head
# for forks use: rvm install ruby-head-<name> --url https://github.com/github/ruby.git --branch 2.2
# JRuby
jruby-1.6[.8]
jruby-1.7[.23]
jruby[-9.0.5.0]
jruby-head
# Rubinius
rbx-1[.4.3]
rbx-2.3[.0]
rbx-2.4[.1]
rbx[-2.5.8]
rbx-head
# Opal
opal
# Minimalistic ruby implementation - ISO 30170:2012
mruby[-head]
# Ruby Enterprise Edition
ree-1.8.6
ree[-1.8.7][-2012.02]
# GoRuby
goruby
# Topaz
topaz
# MagLev
maglev[-head]
maglev-1.0.0
# Mac OS X Snow Leopard Or Newer
macruby-0.10
macruby-0.11
macruby[-0.12]
macruby-nightly
macruby-head
# IronRuby
ironruby[-1.1.3]
ironruby-head
这里我们安装2.2.2:
$rvm install 2.2.2
终端运行结果：（如果直接成功请绕过homebrew的卸载安装）
Searching for binary rubies, this might take some time.
Found remote file https://rvm_io.global.ssl.fastly.net/binaries/osx/10.11/x86_64/ruby-2.2.2.tar.bz2
Checking requirements for osx.
About to install Homebrew, press `Enter` for default installation in `/usr/local`,
type new path if you wish custom Homebrew installation (the path needs to be writable for user)
:
回车：
It appears Homebrew is already installed. If your intent is to reinstall you
should do the following before running this installer again:
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall)"
The current contents of /usr/local are .git
Requirements installation failed with status: 1.
这里执行：
$ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall)"
卸载home-brew
Warning: This script will remove:
/Library/Caches/Homebrew/
/usr/local/.git/
Are you sure you want to uninstall Homebrew? [y/N] y
==> Removing Homebrew installation...
==> Removing empty directories...
==> Homebrew uninstalled!
You may want to restore /usr/local's original permissions
sudo chmod 0755 /usr/local
sudo chgrp wheel /usr/local
再执行：
$ rvm install 2.2.2
提示：
Searching for binary rubies, this might take some time.
Found remote file https://rvm_io.global.ssl.fastly.net/binaries/osx/10.11/x86_64/ruby-2.2.2.tar.bz2
Checking requirements for osx.
About to install Homebrew, press `Enter` for default installation in `/usr/local`,
type new path if you wish custom Homebrew installation (the path needs to be writable for user)
:
按回车：
==> This script will install:
/usr/local/bin/brew
/usr/local/Library/...
/usr/local/share/doc/homebrew
/usr/local/share/man/man1/brew.1
/usr/local/share/zsh/site-functions/_brew
/usr/local/etc/bash_completion.d/brew
Press RETURN to continue or any other key to abort
==> /usr/bin/sudo /bin/mkdir /Library/Caches/Homebrew
Password:
这里需要输入电脑密码：
==> /usr/bin/sudo /bin/chmod g+rwx /Library/Caches/Homebrew
==> /usr/bin/sudo /usr/sbin/chown haha /Library/Caches/Homebrew
==> Downloading and installing Homebrew...
remote: Counting objects: 501, done.
remote: Compressing objects: 100% (445/445), done.
remote: Total 501 (delta 29), reused 360 (delta 27), pack-reused 0
Receiving objects: 100% (501/501), 787.83 KiB | 169.00 KiB/s, done.
Resolving deltas: 100% (29/29), done.
From https://github.com/Homebrew/brew
* [new branch] master -> origin/master
HEAD is now at 32f7e73 download_strategy: ensure fixed commit hash length
==> Tapping homebrew/core
Cloning into '/usr/local/Library/Taps/homebrew/homebrew-core'...
remote: Counting objects: 3714, done.
remote: Compressing objects: 100% (3598/3598), done.
remote: Total 3714 (delta 14), reused 2112 (delta 6), pack-reused 0
Receiving objects: 100% (3714/3714), 2.88 MiB | 240.00 KiB/s, done.
Resolving deltas: 100% (14/14), done.
Checking connectivity... done.
Checking out files: 100% (3717/3717), done.
Tapped 3591 formulae (3,740 files, 9.0M)
==> Installation successful!
==> Next steps
Run `brew help` to get started
Further documentation: https://git.io/brew-docs
==> Homebrew has enabled anonymous aggregate user behaviour analytics
Read the analytics documentation (and how to opt-out) here:
https://git.io/brew-analytics
Installing requirements for osx.
Updating system.....
Installing required packages: autoconf, automake, libtool, pkg-config, libyaml, readline, libksba, openssl........
Certificates in '/usr/local/etc/openssl/cert.pem' are already up to date.
Requirements installation successful.
ruby-2.2.2 - #configure
ruby-2.2.2 - #download
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 6854k 100 6854k 0 0 61342 0 0:01:54 0:01:54 --:--:-- 132k
ruby-2.2.2 - #validate archive
ruby-2.2.2 - #extract
ruby-2.2.2 - #validate binary
ruby-2.2.2 - #setup
ruby-2.2.2 - #gemset created /Users/haha/.rvm/gems/ruby-2.2.2@global
ruby-2.2.2 - #importing gemset /Users/haha/.rvm/gemsets/global.gems..............................
ruby-2.2.2 - #generating global wrappers........
ruby-2.2.2 - #gemset created /Users/haha/.rvm/gems/ruby-2.2.2
ruby-2.2.2 - #importing gemsetfile /Users/haha/.rvm/gemsets/default.gems evaluated to empty gem list
ruby-2.2.2 - #generating default wrappers........
Updating certificates in '/etc/openssl/cert.pem'.
mkdir: /etc/openssl: Permission denied
mkdir -p "/etc/openssl" failed, retrying with sudo
haha password required for 'mkdir -p /etc/openssl':
and sudo mkdir worked
这样ruby2.2.2就安装好了
现在就可以安装cocoapods啦：
安装过程需要稍作等待,成功后会有成功安装的提示，如图所示：
② 设置CocoaPods，终端命令：pod setup
因为文件较大，需要等待，我们可以通过终端命令来查看进度，具体操作如下：
<1> 重新打开一个终端，进入CocoaPods，终端命令：cd ~/.cocoapods
<2> 查看下载进度，终端命令：du -sh *，这个命令只能关注当下一个时间点的进度，需要不断执行这个命令，才能随时关注下载进度
设置成功后终端图片：
3> CocoaPods使用
-
先找到要查找的第三方库，终端命令：pod search + 第三方库名称
-
在列表页面，选择三方库最新版本的命令，例如：pod 'MBProgressHUD','~>0.9.2'
-
创建工程，使用 cd + 工程路径 命令进入工程（直接拖着文件到终端就可得到工程路径）
-
编辑工程的 Podfile 文件，终端命令：vim Podfile
vim 是一个强大的编辑工具，我从网上找到一篇还可以的Vim编辑器使用基础教程，有兴趣的朋友可以看看
-
键盘输入 " i " 使 Podfile 处于编辑状态，然后将以下内容写入（高版本）：
platform :ios, '8.0' use_frameworks! target 'MyApp（你现在项目文件夹名）' do pod 'MBProgressHUD', '~> 0.9.2' // 最新版本的第三方命令 end
在编辑完成后，按下esc键，再按下 " : "，此时，输入 "wq" 再按回车，保存并退出。
- 进行更新下载三方库，终端命令：pod update
pod install --verbose --no-repo-update (先检查一下有没有，有就不下载，没有就下载，建议使用这个)
- 回到你的工程所在的目录,会发现现在多了很多文件,此时我们应该使用 .xcworkspace文件打开项目，而不在用.xcodeproj文件打开。
4> CococaPods可能报错及解决方式
- pod setup -bash: pod: command not found
升级10.11后使用CocoaPod出现-bash: pod: command not found
解决办法：sudo gem install -n /usr/local/bin cocoapods
- The dependency `MBProgressHUD (~> 1.0.1)` is not used in any concrete target.
原因：CocoaPods升级到最新版本（包括一些高版本），Podfile文件的内容必须明确指出所用第三方库的targetName.
报错分析：低版本和高版本写法不一样.
低版本：
platform :ios, '8.0'
pod 'MBProgressHUD', '~> 0.9.2'
高版本：
platform :ios, '8.0'
target "targetName" do
pod 'MBProgressHUD', '~> 0.9.2'
end
还会有其他的一些小的容易的错误，比如：在Podfile文件中将使用中文输入法的标点符号，ios写为iOS等等，大家可以根据报错自行处理
