How to take screenshot at the point where test fail in Espresso?

Question

I am looking for a way to take a screenshot of device after test failed and before get closed.

Answer 1

Easiest way that I found:

@Rule
public TestRule watcher = new TestWatcher() {
  @Override
  protected void failed(Throwable e, Description description) {
    // Save to external storage (usually /sdcard/screenshots)
    File path = new File(Environment.getExternalStorageDirectory().getAbsolutePath()
        + "/screenshots/" + getTargetContext().getPackageName());
    if (!path.exists()) {
      path.mkdirs();
    }

    // Take advantage of UiAutomator screenshot method
    UiDevice device = UiDevice.getInstance(InstrumentationRegistry.getInstrumentation());
    String filename = description.getClassName() + "-" + description.getMethodName() + ".png";
    device.takeScreenshot(new File(path, filename));
  }
};