I'm trying to use Android UIAutomator for some simple tests, I'm aware of that it needs to be built by Gradle since UIAutomator 2.0, I can run my simple test which only presses home button via Android Studio or command line by "gradlew.bat cC", I was wondering how I can run it with adb command?
I tried
adb shell am instrument -w test.simple.uiatest/android.test.InstrumentationTestRunner
as suggested here , but I get
INSTRUMENTATION_STATUS: id=ActivityManagerService
INSTRUMENTATION_STATUS: Error=Unable to find instrumentation info for: ComponentInfo{test.simple.uiatest/android.test.InstrumentationTestRunner}
INSTRUMENTATION_STATUS_CODE: -1
android.util.AndroidException: INSTRUMENTATION_FAILED: test.simple.uiatest/android.test.InstrumentationTestRunner
    at com.android.commands.am.Am.runInstrument(Am.java:951)
    at com.android.commands.am.Am.onRun(Am.java:316)
    at com.android.internal.os.BaseCommand.run(BaseCommand.java:47)
    at com.android.commands.am.Am.main(Am.java:99)
    at com.android.internal.os.RuntimeInit.nativeFinishInit(Native Method)
    at com.android.internal.os.RuntimeInit.main(RuntimeInit.java:250)
Below are my code snippet and build.gradle, what am I doing wrong?
package test.simple.uiatest;
import android.support.test.uiautomator.UiDevice;
import android.test.InstrumentationTestCase;
public class ApplicationTest extends InstrumentationTestCase {
    private UiDevice theDevice;
    @Override
    public void setUp() throws Exception {
        super.setUp();
        theDevice = UiDevice.getInstance(getInstrumentation());
        theDevice.pressHome();
    }
    public void testName() throws Exception {
        theDevice.pressHome();
    }
}
build.gradle
apply plugin: 'com.android.application'
android {
    compileSdkVersion 22
    buildToolsVersion "23.0.0 rc2"
    defaultConfig {
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        applicationId "test.simple.uiatest"
        minSdkVersion 21
        targetSdkVersion 22
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    packagingOptions {
        exclude 'LICENSE.txt'
    }
}
dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile 'com.android.support.test:runner:0.2'
    androidTestCompile 'com.android.support.test:rules:0.2'
    androidTestCompile 'com.android.support.test.uiautomator:uiautomator-v18:2.1.0'
}
				
                        
The error you're seeing will occur if the test APK is not installed, or if the <test_package>/<runner_class> in your
am instrument ...command is wrong.To list the instrumentation tests that are available on your device, you can run
adb shell pm list instrumentation. You should see a line like:If you don't see a line matching your test, then you need to install the test APK. If it is installed, double check that the
test.simple.uiatest/android.test.InstrumentationTestRunnerportion of thepm list instrumentationoutput matches youram instrumentcommand.