问有没有可能使用Espresso的IdlingResource来等待某个视图出现？

EN

import android.support.test.espresso.IdlingResource;
import android.support.test.espresso.ViewFinder;
import android.support.test.espresso.ViewInteraction;
import android.view.View;

import org.hamcrest.Matcher;

import java.lang.reflect.Field;

import static android.support.test.espresso.Espresso.onView;

public class ViewShownIdlingResource implements IdlingResource {

    private static final String TAG = ViewShownIdlingResource.class.getSimpleName();

    private final Matcher<View> viewMatcher;
    private ResourceCallback resourceCallback;

    public ViewShownIdlingResource(final Matcher<View> viewMatcher) {
        this.viewMatcher = viewMatcher;
    }

    @Override
    public boolean isIdleNow() {
        View view = getView(viewMatcher);
        boolean idle = view == null || view.isShown();

        if (idle && resourceCallback != null) {
            resourceCallback.onTransitionToIdle();
        }

        return idle;
    }

    @Override
    public void registerIdleTransitionCallback(ResourceCallback resourceCallback) {
        this.resourceCallback = resourceCallback;
    }

    @Override
    public String getName() {
        return this + viewMatcher.toString();
    }

    private static View getView(Matcher<View> viewMatcher) {
        try {
            ViewInteraction viewInteraction = onView(viewMatcher);
            Field finderField = viewInteraction.getClass().getDeclaredField("viewFinder");
            finderField.setAccessible(true);
            ViewFinder finder = (ViewFinder) finderField.get(viewInteraction);
            return finder.getView();
        } catch (Exception e) {
            return null;
        }
    }
}

public void waitViewShown(Matcher<View> matcher) {
    IdlingResource idlingResource = new ViewShownIdlingResource(matcher);///
    try {
        IdlingRegistry.getInstance().register(idlingResource);
        onView(matcher).check(matches(isDisplayed()));  
    } finally {
        IdlingRegistry.getInstance().unregister(idlingResource);
    }    
}

@Test
public void someTest() {
    waitViewShown(withId(R.id.<some>));

    //do whatever verification needed afterwards    
} 

/**
 * {@link IdlingResource} that idles until a {@link View} condition is fulfilled.
 */
public class ViewIdlingResource implements IdlingResource {

    private final Matcher<View>    viewMatcher;
    private final Matcher<View>    idleMatcher;
    private       ResourceCallback resourceCallback;

    /**
     * Constructor.
     *
     * @param viewMatcher The matcher to find the view.
     * @param idlerMatcher The matcher condition to be fulfilled to be considered idle.
     */
    public ViewIdlingResource(final Matcher<View> viewMatcher, Matcher<View> idlerMatcher) {
        this.viewMatcher = viewMatcher;
        this.idleMatcher = idlerMatcher;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isIdleNow() {
        View view = getView(viewMatcher);
        boolean isIdle = idleMatcher.matches(view);

        if (isIdle && resourceCallback != null) {
            resourceCallback.onTransitionToIdle();
        }

        return isIdle;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void registerIdleTransitionCallback(ResourceCallback resourceCallback) {
        this.resourceCallback = resourceCallback;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getName() {
        return this + viewMatcher.toString();
    }

    /**
     * Tries to find the view associated with the given {@link Matcher<View>}.
     */
    private static View getView(Matcher<View> viewMatcher) {
        try {
            ViewInteraction viewInteraction = onView(viewMatcher);
            Field finderField = viewInteraction.getClass().getDeclaredField("viewFinder");
            finderField.setAccessible(true);
            ViewFinder finder = (ViewFinder) finderField.get(viewInteraction);
            return finder.getView();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}

private void waitUntilViewIsDisplayed(Matcher<View> matcher) {
        IdlingResource idlingResource = new ViewIdlingResource(matcher, isDisplayed());
        try {
            IdlingRegistry.getInstance().register(idlingResource);
            // First call to onView is to trigger the idler.
            onView(withId(0)).check(doesNotExist());
        } finally {
            IdlingRegistry.getInstance().unregister(idlingResource);
        }
    }

    private const val sleepTime = 1000L
    private const val maximumWaitedTime = 10000L // maximum waited time in milliseconds to wait a view visible

    fun waitViewVisible(viewInteraction: ViewInteraction?, block: (() -> Unit)? = null) {
        waitAssertView(viewInteraction, ViewAssertions.matches(isDisplayed()), block)
    }

    fun waitViewGone(viewInteraction: ViewInteraction?, block: (() -> Unit)? = null) {
        waitAssertView(viewInteraction, ViewAssertions.matches(not(isDisplayed())), block)
    }

    fun waitAssertView(viewInteraction: ViewInteraction?, assertion: ViewAssertion?, block: (() -> Unit)? = null) {
            if (viewInteraction == null || assertion == null) throw NullPointerException()
            val startedTime: Long = System.currentTimeMillis()
            var elapsedTime: Long = 0
            var isVisible = false
            do {
                isVisible = runCatching {
                    viewInteraction.check(assertion)
                }.isSuccess
                if (isVisible) break
                Thread.sleep(sleepTime)
                elapsedTime = System.currentTimeMillis() - startedTime
            } while (elapsedTime <= maximumWaitedTime)
            if (!isVisible) throw TimeoutException("Waited time exceed the maximum waited time")

            block?.invoke()
        }