When you trying to build android for ionic or cordova in linux(ubuntu) but its showing you an error like this:
ubuntu下，当你使用ionic或者cordova build android 命令编译时，出现如下错误：
[Error: Failed to find ‘ANDROID_HOME’ environment variable.
Try setting setting it manually.
Failed to find ‘android’ command in your ‘PATH’.
Try update your ‘PATH’ to include path to valid SDK directory.]
you can do like this:
你可以通过配置环境变量解决：
echo ‘export ANDROID_HOME=”‘$HOME’/your-android-sdk-dir”‘ >> ~/.bashrc
echo ‘export PATH=”$PATH:$ANDROID_HOME/tools:$ANDROID_HOME/platform-tools”‘ >> ~/.bashrc
echo ‘export JAVA_CMD=”/usr/lib/jvm/java-7-openjdk-amd64/bin/java”‘ >> ~/.bashrc
reentry your terminal use
然后，关掉你的终端，重新打开使环境变量生效，再输入：
source ~/.bashrc
done，that is ok！
这样就搞定了