Dependencies under Linux headache, especially when prompt the following error:
下列软件包有未满足的依赖关系：
xxx : 依赖: xxx 但是它将不会被安装
E: 无法修正错误，因为您要求某些软件包保持现状，就是它们破坏了软件包间的依赖关系。Checked, because there are a lot of packages to be installed need to rely on lower-level packages, it can be sudo aptitude installto try to solve the problem by downgrading.
For example, I want to install libgtk2.0-dev, but these goods are dependent on an earlier version of the package, this package can not lead to the installation, the solution is as follows:
sudo apt-get install aptitude
# 安装 aptitude 包管理器
sudo aptitude install libgtk2.0-dev
# 提示未满足依赖关系，给出了类似1) libcairo2-dev [未安装的] 等提示，问是否接受该解决方案？[Y/n/q/?]
n
# 不接受该解决方案，然后会提示降级下列软件包，问是否接受该解决方案？[Y/n/q/?]
y
# 接受降级，此时会发现新安装包列表里果然有libgtk2.0-dev，然后会提示您要继续吗？[Y/n/?]
y
# 继续，确认安装
# 安装成功！其他搞不定的包也可以如此尝试，不过降级之前需要仔细看下版本号变化，如果差太多还需要慎重考虑