No installed build tools found

问题描述：

BUILD FAILED

Total time: 2.235 secs
--stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
Error: cmd: Command failed with exit code 1 Error output:
Failed to notify ProjectEvaluationListener.afterEvaluate(), but primary configuration failure takes precedence.
java.lang.IllegalStateException: buildToolsVersion is not specified.
        at com.google.common.base.Preconditions.checkState(Preconditions.java:173)
        at com.android.build.gradle.BasePlugin.createAndroidTasks(BasePlugin.java:645)
        at com.android.build.gradle.BasePlugin$10.call(BasePlugin.java:608)
        at com.android.build.gradle.BasePlugin$10.call(BasePlugin.java:605)
        at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:156)
        at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:120)
        at com.android.build.gradle.BasePlugin.lambda$createTasks$1(BasePlugin.java:603)
        at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:93)
        at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:82)
        at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:44)
        at org.gradle.internal.event.BroadcastDispatch.dispatch(BroadcastDispatch.java:79)
        at org.gradle.internal.event.BroadcastDispatch.dispatch(BroadcastDispatch.java:30)
        at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
        at com.sun.proxy.$Proxy16.afterEvaluate(Unknown Source)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.notifyAfterEvaluate(LifecycleProjectEvaluator.java:82)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.doConfigure(LifecycleProjectEvaluator.java:76)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.access$000(LifecycleProjectEvaluator.java:33)
        at org.gradle.configuration.project.LifecycleProjectEvaluator$1.execute(LifecycleProjectEvaluator.java:53)
        at org.gradle.configuration.project.LifecycleProjectEvaluator$1.execute(LifecycleProjectEvaluator.java:50)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:61)
        at org.gradle.configuration.project.LifecycleProjectEvaluator.evaluate(LifecycleProjectEvaluator.java:50)
        at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:628)
        at org.gradle.api.internal.project.DefaultProject.evaluate(DefaultProject.java:129)
        at org.gradle.execution.TaskPathProjectEvaluator.configure(TaskPathProjectEvaluator.java:35)
        at org.gradle.execution.TaskPathProjectEvaluator.configureHierarchy(TaskPathProjectEvaluator.java:60)
        at org.gradle.configuration.DefaultBuildConfigurer.configure(DefaultBuildConfigurer.java:38)
        at org.gradle.initialization.DefaultGradleLauncher$1.execute(DefaultGradleLauncher.java:161)
        at org.gradle.initialization.DefaultGradleLauncher$1.execute(DefaultGradleLauncher.java:158)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:56)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:158)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:119)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:102)
        at org.gradle.launcher.exec.GradleBuildController.run(GradleBuildController.java:71)
        at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:41)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:75)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:49)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:44)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:29)
        at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:47)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
        at org.gradle.util.Swapper.swap(Swapper.java:38)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:72)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
        at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:297)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
        at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

FAILURE: Build failed with an exception.

* Where:
Script 'D:\test\platforms\android\CordovaLib\cordova.gradle' line: 64

* What went wrong:
A problem occurred evaluating root project 'android'.
> No installed build tools found. Install the Android build tools version 19.1.0 or higher.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

stackoverflow.com的解决方法

You are missing android SDK tools. Please try the following:

android list sdk --all 
android update sdk -u -a -t 

Where

-u (--no-ui)  # Headless mode
-a (--all)    # Includes all packages (also obsolete ones)
-t (--filter) # Filter by package index

The following commands can update Android SDK on Ubuntu quickly and fix the above error:

android list sdk --all
android update sdk -u -a -t 19
android update sdk -u -a -t 20

最主要的是下面的解决方案：也是从stackoverflow.com获取到的，步骤：

1 : It really really really did not found build tools

2 : To make him find build tools you need to define these paths correctly

PATH IS SAME FOR UBUNTU(.bashrc) AND MAC(.bash_profile)

export ANDROID_HOME=/Users/vijay/Software/android-sdk-macosx
export PATH=${PATH}:/Users/vijay/Software/android-sdk-macosx/tools
export PATH=${PATH}:/Users/vijay/Software/android-sdk-macosx/platform-tools

3 : IMPORTANT IMPORTANT as soon as you set environmental variables you need to reload evnironmental variables.

//For ubuntu
$source .bashrc 

//For macos
$source .bash_profile

4 : Then check in terminal

$printenv ANDROID_HOME
$printenv PATH

Note : if you did not find your changes in printenv then restart the pc and try again printenv PATH, printenv ANDROID_HOME .There is also command to reload environmental variables .

解决步骤：

执行

android list sdk --all
android update sdk -u -a -t 19
android update sdk -u -a -t 20

这三条命令以后发现还是不能build，出现的还是这个问题
然后往下看发现上面的四个步骤，第一条就直接确定是没有找到build-tools
那就说明还是环境没有找到，配置的环境变量还是有问题，再次在cmd.exe中输入android命令，
发现还是可以执行SDK Manager.exe这个程序的，但是执行ionic build android就报错找不到build-tools这个
文件夹，然后查看正在使用的用户的ANDROID_HOME的环境变量，发现他是配置到
++C:\Users\user\AppData\Local\Android\Sdk++
而系统环境变量是配置到
++D:\Android\sdk++
一开始总认为只要系统环境变量配置好以后，windows用户的环境变量如果找不到会采用系统的环境变量，结果不管怎么配置在build的时候总是不成功，就想到要不把用户的环境变量也改过来尝试一下，再次build的时候居然成功了，说明系统环境变量还是和用户的环境变量有区别的。

本次出现的问题总结：

这次Windows自动更新以后出现这个问题的原因是由于更新以后原来ANDROID_HOME配置到

C:\Users\wuhan\AppData\Local\Android\Sdk

文件夹下的一些文件全部删除了，包括SDK Manager.exe、AVD Manager.exe 以及与他平级的platform-tools、tools
等所有的文件夹全部删除了，所以找不到配置文件导致的，所以将登陆电脑使用的用户的ANDROID_HOMe的环境变量改成和系统使用用户一样的，能找到这些文件和文件夹的目录配置成功就可以