//从git上clone
1、打开命令行窗口，输入以下命令
git clone -b beta https://github.com/flutter/flutter.git
2、配置环境变量
2.1 sudo vi .bash_profile， 按i进入编辑模式，输入export PATH=`pwd`/flutter/bin:$PATH，并按ESC，再输入:wq， 保存退出
3、输入flutter doctor 检查安装缺失相，按提示，进行相应安装
若执行flutter doctor出现以下错误：
⣽Unhandled exception:
Exception: idevice_id returned an error:
#0 IMobileDevice.getInfoForDevice (package:flutter_tools/src/ios/mac.dart:122:9)
<asynchronous suspension>
#1 IOSDevice.getAttachedDevices (package:flutter_tools/src/ios/devices.dart:152:53)
<asynchronous suspension>
#2 IOSDevices.pollingGetDevices (package:flutter_tools/src/ios/devices.dart:112:57)
#3 PollingDeviceDiscovery.devices (package:flutter_tools/src/device.dart:163:52)
<asynchronous suspension>
#4 DeviceManager.getAllConnectedDevices (package:flutter_tools/src/device.dart:91:46)
<asynchronous suspension>
#5 DeviceValidator.validate (package:flutter_tools/src/doctor.dart:677:54)
<asynchronous suspension>
#6 Doctor.startValidatorTasks (package:flutter_tools/src/doctor.dart:107:52)
#7 Doctor.diagnose (package:flutter_tools/src/doctor.dart:174:41)
#8 _AsyncAwaitCompleter.start (dart:async/runtime/libasync_patch.dart:49:6)
#9 Doctor.diagnose (package:flutter_tools/src/doctor.dart:164:24)
#10 DoctorCommand.runCommand (package:flutter_tools/src/commands/doctor.dart:29:39)
#11 _AsyncAwaitCompleter.start (dart:async/runtime/libasync_patch.dart:49:6)
#12 DoctorCommand.runCommand (package:flutter_tools/src/commands/doctor.dart:28:42)
#13 FlutterCommand.verifyThenRunCommand (package:flutter_tools/src/runner/flutter_command.dart:383:18)
#14 _asyncThenWrapperHelper.<anonymous closure> (dart:async/runtime/libasync_patch.dart:77:64)
#15 _rootRunUnary (dart:async/zone.dart:1132:38)
#16 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#17 _FutureListener.handleValue (dart:async/future_impl.dart:129:18)
#18 Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:642:45)
#19 Future._propagateToListeners (dart:async/future_impl.dart:671:32)
#20 Future._complete (dart:async/future_impl.dart:476:7)
#21 _SyncCompleter.complete (dart:async/future_impl.dart:51:12)
#22 _AsyncAwaitCompleter.complete.<anonymous closure> (dart:async/runtime/libasync_patch.dart:33:20)
#23 _rootRun (dart:async/zone.dart:1124:13)
#24 _CustomZone.run (dart:async/zone.dart:1021:19)
#25 _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:947:23)
#26 _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#27 _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
#28 _runPendingImmediateCallback (dart:isolate/runtime/libisolate_patch.dart:115:13)
#29 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:172:5)
此时可以依次执行以下命令解决：
brew uninstall ideviceinstaller
brew uninstall libimobiledevice
brew install --HEAD libimobiledevice
brew link --overwrite libimobiledevice
brew install --HEAD ideviceinstaller
brew link --overwrite ideviceinstaller
