如何在Android Espresso上检查/测试Snackbar解雇

Question

I wanted to test if at all possible Espresso knows how to check Snackbar dismissal? I am currently deleting a tag and shows a Snackbar giving the user a chance to undo. I delete the tag after a Snackbar.LEGNTH_LONG and I wanted to test if my tag is still on the list after Snackbar.LEGNTH_LONG .

I haven't figured this out yet. Is this possible on Espresso?

Answer 1

You can add this class to your project: https://android.googlesource.com/platform/frameworks/support/+/a1de3ee/design/tests/src/android/support/design/testutils/SnackbarUtils.java

it's an utils class which contains this method:

/**
 * Helper method that dismissed that specified {@link Snackbar} and waits until
 * it has been fully dismissed. Note that calling this method will reset the currently
 * set {@link Snackbar.Callback}.
 */
public static void dismissSnackbarAndWaitUntilFullyDismissed(Snackbar snackbar) {
    SnackbarDismissedCallback snackbarCallback = new SnackbarDismissedCallback();
    snackbar.setCallback(snackbarCallback);
    try {
        // Register our listener as idling resource so that Espresso waits until the
        // the snackbar has been fully dismissed
        Espresso.registerIdlingResources(snackbarCallback);
        // Dismiss the snackbar
        snackbar.dismiss();
        // Mark the callback to require waiting for idle state
        snackbarCallback.mNeedsIdle = true;
        // Perform a dummy Espresso action that loops until the UI thread is idle. This
        // effectively blocks us until the Snackbar has completed its sliding animation.
        onView(isRoot()).perform(waitUntilIdle());
        snackbarCallback.mNeedsIdle = false;
    } finally {
        // Unregister our idling resource
        Espresso.unregisterIdlingResources(snackbarCallback);
        // And remove our tracker listener from Snackbar
        snackbar.setCallback(null);
    }
}

and then execute:

SnackbarUtils.dismissSnackbarAndWaitUntilFullyDismissed(snackbar);

in your test before checking if your tag is still on the list. I haven't tested this but I think it should work.