gistfile1.java

package com.testexample.RunListeners

import android.support.test.InstrumentationRegistry;
import android.support.test.uiautomator.UiDevice;

import org.junit.runner.Description;
import org.junit.runner.notification.Failure;
import org.junit.runner.notification.RunListener;

import java.io.File;
import java.IOException;

/**
 * Use this RunListener when you want to capture screenshots on test failures for UI tests.
 * To specify one or more RunListeners to observe the test run: -e listener com.foo.Listener,com.foo.Listener2
 * 
 */
public class ExampleScreenshotOnUITestFailureListener extends RunListener {
  Description desc;

  public void testStarted (Description description) { desc = description; }
  public void testFailure (Failure failure) throws IOException {
    
    // build filename from class and method using .png as the file type
    String name = String.format("%s.%s.png",
      desc.getClassName(),
      desc.getMethodName());
      
    // my tests all use String OUTPUT_DIR = "/sdcard/test_output_files/" for screenshots and other artifacts
    File file = new File(OUTPUT_DIR, name);
    
    // take the screenshot already
    UiDevice.getInstance(InstrumentationRegistry.getInstrumentation()).takeScreenshot(file);
  } 
}