即使我在后台运行了模拟器，也无法运行我的React本机代码

Question

I am trying to run react native code but when I use react-native run-android I get this error message. I am using android studio.

~/Downloads/BrainG-master$ sudo react-native run-android

Scanning folders for symlinks in /home/luke/Downloads/BrainG-
master/node_modules (10ms)

JS server already running.

Building and installing the app on the device (cd android && ./gradlew 
installDebug)...

: No such file or directory

Could not install the app on the device, read the error above for 
details.
Make sure you have an Android emulator running or a device connected 
and have
set up your Android development environment:

Answer 1

Make sure

1. there is an android directory inside /Downloads/BrainG-master (I hope you're not running react-native run-android from within the android directory) and

2. your local.properties file in BrainG-master/android has the location of your android SDK specified in the following format: sdk.dir=/Users/username/pathToYourAndroidSdk .

If there is no local.properties file, open the project in Android Studio and it will create that for you.

If you're on Linux, you can also configure the android home environment thus:

Add the following lines to your $HOME/.bash_profile config file:

export ANDROID_HOME=$HOME/Android/Sdk

export PATH=$PATH:$ANDROID_HOME/tools

export PATH=$PATH:$ANDROID_HOME/platform-tools

.bash_profile is specific to bash . If you're using another shell, you will need to edit the appropriate shell-specific config file.

Type source $HOME/.bash_profile to load the config into your current shell. Verify that ANDROID_HOME has been added to your path by running echo $PATH .

You can follow the instructions here: https://facebook.github.io/react-native/docs/getting-started.html#2-install-the-android-sdk