com.android.builder.testing.api.DeviceException: No connected devices

Question

Scanning folders for symlinks in /home/sino/Desktop/we-clone/node_modules (4ms)
Starting JS server...
Building and installing the app on the device (cd android && ./gradlew installDebug)...
Incremental java compilation is an incubating feature.
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72301Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42301Library UP-TO-DATE
:app:prepareComFacebookFbuiTextlayoutbuilderTextlayoutbuilder100Library UP-TO-DATE
:app:prepareComFacebookFrescoDrawee130Library UP-TO-DATE
:app:prepareComFacebookFrescoFbcore130Library UP-TO-DATE
:app:prepareComFacebookFrescoFresco130Library UP-TO-DATE
:app:prepareComFacebookFrescoImagepipeline130Library UP-TO-DATE
:app:prepareComFacebookFrescoImagepipelineBase130Library UP-TO-DATE
:app:prepareComFacebookFrescoImagepipelineOkhttp3130Library UP-TO-DATE
:app:prepareComFacebookReactReactNative0493Library UP-TO-DATE
:app:prepareComFacebookSoloaderSoloader010Library UP-TO-DATE
:app:prepareOrgWebkitAndroidJscR174650Library UP-TO-DATE
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:mergeDebugShaders UP-TO-DATE
:app:compileDebugShaders UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:generateDebugResources UP-TO-DATE
:app:mergeDebugResources UP-TO-DATE
:app:bundleDebugJsAndAssets SKIPPED
:app:processDebugManifest UP-TO-DATE
:app:processDebugResources UP-TO-DATE
:app:generateDebugSources UP-TO-DATE
:app:incrementalDebugJavaCompilationSafeguard UP-TO-DATE
:app:compileDebugJavaWithJavac UP-TO-DATE
:app:compileDebugNdk UP-TO-DATE
:app:compileDebugSources UP-TO-DATE
:app:transformClassesWithDexForDebug UP-TO-DATE
:app:mergeDebugJniLibFolders UP-TO-DATE
:app:transformNative_libsWithMergeJniLibsForDebug UP-TO-DATE
:app:processDebugJavaRes UP-TO-DATE
:app:transformResourcesWithMergeJavaResForDebug UP-TO-DATE
:app:validateSigningDebug
:app:packageDebug UP-TO-DATE
:app:assembleDebug UP-TO-DATE
:app:installDebug
07:52:34 E/adb: * daemon not running; starting now at tcp:5037
07:52:37 E/adb: * daemon started successfully
:app:installDebug FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:installDebug'.
> com.android.builder.testing.api.DeviceException: No connected devices!

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

BUILD FAILED

Total time: 8.916 secs
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:
https://facebook.github.io/react-native/docs/android-setup.html

Assignee

In my case turning off USB Debugging then Turn it on solved the problem – Amateurish

Answer 1

If you have android studio installed(if not install it) launch android studio with a dummy project, go to Tools -> AVD Manager. Make sure that you create a virtual device and start it.

Note: To create this virtual device you will need to download and install a compatible OS (compatible with your project's Android SDK version - SDK version can be found inside build.gradle file) on it before launching. AVD Manager will guide you with the process.

Another thing, you may be using a real Android device not an emulator and still get this message. If your device is connected through USB to your laptop you need to first enable the developer options:

If using stock Android, go to Settings > About phone > Build number. On a Samsung Galaxy device, go to Settings > About device > Build number. On an HTC device, go to Settings > About > Software information > More > Build number. On an LG device, go to Settings > About phone > Software info > Build number. Tap Build number seven times. After the first few taps, you should see the steps counting down until you unlock the developer options. Once activated, you will see a message that reads, “You are now a developer!” Go back to Settings, where you’ll find a Developer options entry in the menu. (https://www.digitaltrends.com/mobile/how-to-get-developer-options-on-android/)

Then inside developer options, you should enable USB debugging.

Colure

I had missing AVD manager in menu, i found solution here #37850750 – Wot

thanks this was very helpful. After implementing your instruction. I click on the play button on the android studio then the app display on my emulator then I stopped it then I make use of the run command through the cli $ npx react-native run-android Now the app was repushed to the emulator – Shalloon

Answer 2

You'll need to have an Android Emulator running or a physical device connected and in usb debugging mode.

See https://facebook.github.io/react-native/docs/getting-started.html#preparing-the-android-device for more information.

Impressible

This link is broken – Iives

this is the instruction for react native setup now: reactnative.dev/docs/environment-setup – Chancellorship

Answer 3

Looks like Version SDK is incompatible. Check the SDK version in build.gradle under the android folder.

For example

ext {
    buildToolsVersion = "29.0.2"
    minSdkVersion = 16
    compileSdkVersion = 29
    targetSdkVersion = 29
}

Then download the emulator from the AVD Manager like below.

Select Image API Level 29 (Follow SDK version)

Cyrillus

Answer 4

In my case, my usb wasn't connected for some reason, even though it seemed like it was physically connected. I had to change the ports I used.

Valenba

In my case enabling USB debugging cleared the error – Robustious

Answer 5

In my case I had two virtual devices set up in Android Studio. The first one was not compatible with React Native (e.g. needing Tiramisu API Level 33 as per https://reactnative.dev/docs/environment-setup?guide=native). The second one was compatible. When I deleted the first one, then everything worked.

Snaky