"RuntimeException: Could not launch activity...Unable to resolve activity for Intent" when running Jetpack Compose UI tests with createComposeRule

Question

Running tests with createComposeRule and hitting a stack trace like (irrelevant parts omitted):

java.lang.RuntimeException: Could not launch activity
at androidx.test.runner.MonitoringInstrumentation.startActivitySync(MonitoringInstrumentation.java:495)
...
Caused by: java.lang.RuntimeException: Unable to resolve activity for: Intent { act=android.intent.action.MAIN flg=0x14000000 cmp=my.app.package.name.here/android.app.Activity }
...

Answer 1

The OP question is about the use of createComposeRule() which doesn't require a custom activity (it uses ComposeActivity under the hood).

In this case you need to include this below in your gradle file:

debugImplementation("androidx.compose.ui:ui-test-manifest:1.0.0-beta05")

If you take a look at the contents of that package, it's simply an AndroidManifest.xml with an <activity/> entry for androidx.activity.ComponentActivity.

Answer 2

You need to add

<activity android:name="androidx.activity.ComponentActivity" />

to your manifest.