title: Espresso - Custom find view got uncaught NoMatchingViewException - without IdlingResource
body: <p>Here, I want a custom find view function: if with a given Matcher can NOT found the view in 10 seconds, return a boolean false, otherwise return the view. Note, I dont want use IdlingResource. My code is as below:</p>
  
  <p><strong>AiFinder.java</strong></p>
  
  <pre><code>package BaseOpration;
  import android.support.test.espresso.NoMatchingViewException;
  import android.support.test.espresso.ViewAssertion;
  import android.support.test.espresso.ViewInteraction;
  import android.view.View;
  
  import org.hamcrest.Matcher;
  import static android.support.test.espresso.Espresso.onView;
  
  /**
   * Created by Real on 2018/3/14.
   */
  
  public class AiFinder {
  
      public static Object findElement(Matcher&lt;View&gt; matcher){
          int times = 0;
          while(times &lt; Configer.timeOut){
              try{
                  return onView(matcher);
              }
              catch (NoMatchingViewException ex){
                  try {
                      System.out.printf("Retrying...");
                      Thread.sleep(1000);
                  } catch (Exception e) {
  //                    e.printStackTrace();
                      System.out.printf("111");
                  }
                  times += 1;
              }
          }
          return false;
      }
  
      public static void checkMatch(Object element, ViewAssertion assertion){
          if(element instanceof Boolean){
              try {
                  throw new Exception("Can not find the view");
              } catch (Exception e) {
                  e.printStackTrace();
              }
          }
          else{
              ViewInteraction e = (ViewInteraction) element;
              e.check(assertion);
          }
      }
  }
  </code></pre>
  
  <p>and my test code:</p>
  
  <pre><code>    @Test
      public void testLogin() throws Exception{
          onView(withId(R.id.tv_main_username)).perform(click());
          onView(withId(R.id.et_username)).perform(clearText(), replaceText("xxx"), closeSoftKeyboard());
          onView(withId(R.id.et_password)).perform(clearText(), replaceText("xxxx"), closeSoftKeyboard());
          onView(withId(R.id.bt_user_login)).perform(click());
          Object userName = AiFinder.findElement(withId(R.id.tv_main_username));
          AiFinder.checkMatch(userName, matches(withText("Hello")));
      }
  </code></pre>
  
  <p>Actually, I see it enters the username and password and after click the login button it gives the output:</p>
  
  <pre><code>$ adb shell am instrument -w -r   -e debug false -e class **.**.AutomationEspressoTest#testLogin **.**.test/android.support.test.runner.AndroidJUnitRunner
  Client not ready yet..
  Started running tests
  
  android.support.test.espresso.NoMatchingViewException: No views in hierarchy found matching: with id: **.**:id/tv_main_username
  
  View Hierarchy:
  .............
  
  at dalvik.system.VMStack.getThreadStackTrace(Native Method)
  at java.lang.Thread.getStackTrace(Thread.java:595)
  at android.support.test.espresso.base.DefaultFailureHandler.getUserFriendlyError(DefaultFailureHandler.java:92)
  at android.support.test.espresso.base.DefaultFailureHandler.handle(DefaultFailureHandler.java:56)
  at android.support.test.espresso.ViewInteraction.runSynchronouslyOnUiThread(ViewInteraction.java:184)
  at android.support.test.espresso.ViewInteraction.check(ViewInteraction.java:158)
  at BaseOpration.AiFinder.checkMatch(AiFinder.java:49)
  at com.hongfans.rearview.AutomationEspressoTest.testLogin(AutomationEspressoTest.java:63)
  at java.lang.reflect.Method.invoke(Native Method)
  at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
  at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
  at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
  at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
  at android.support.test.internal.statement.UiThreadStatement.evaluate(UiThreadStatement.java:55)
  at android.support.test.rule.ActivityTestRule$ActivityStatement.evaluate(ActivityTestRule.java:270)
  at org.junit.rules.RunRules.evaluate(RunRules.java:20)
  at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
  at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
  at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
  at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
  at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
  at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
  at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
  at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
  at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
  at org.junit.runners.Suite.runChild(Suite.java:128)
  at org.junit.runners.Suite.runChild(Suite.java:27)
  at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
  at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
  at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
  at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
  at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
  at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
  at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
  at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
  at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:59)
  at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:262)
  at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1904)
  
  Tests ran to completion.
  </code></pre>
  
  <p>Shouldn't it try to find the view every 1 second? And if failed(because I shut down the network), give me a tag false, and raise the Exception("Can not find the view")? Hope someone can help me out(if I have made any code mistaken). Much Appreciate in advance.:)</p>