title: onClick button to another activity crashes emulator
body: <p>I am completely new to Android studio. I have been trying to create a list of buttons which take the user to the different activities ("movieShowings" in this instance).</p>
  
  <p>When I click on the button however the app crashes on the emulator.</p>
  
  <p>Main Activity</p>
  
  <pre><code>import android.content.Intent;
  import android.support.v7.app.AppCompatActivity;
  import android.os.Bundle;
  import android.view.View;
  
  
  public class MainActivity extends AppCompatActivity {
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
  
  
  }
  
  public void MovieShowings(View view) {
  
      Intent intent = new Intent(this, MovieShowings.class);
      startActivity(intent);
  }
  </code></pre>
  
  <p>}</p>
  
  <p>layout Button</p>
  
  <pre><code>&lt;Button
          android:id="@+id/showingTimes"
          android:layout_width="0dp"
          android:layout_height="48dp"
          android:layout_marginTop="124dp"
          android:text="Movie Showings"
          android:textColor="#0000ff"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent"
          android:onClick="MovieShowings"/&gt;
  </code></pre>
  
  <p>activity_Main</p>
  
  <pre><code>public class MovieShowings extends Activity {
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
  
      String[] foods = {"Bad Boys", "Purge", "Interstellar", "7 Pounds"};
      ListAdapter Adapter = new ArrayAdapter&lt;String&gt;(this, android.R.layout.simple_list_item_1, foods);
      ListView movieList = (ListView) findViewById(R.id.movieList);
      movieList.setAdapter(Adapter);
  
      movieList.setOnItemClickListener(
              new AdapterView.OnItemClickListener(){
                  @Override
                  public void onItemClick(AdapterView&lt;?&gt; parent, View view, int position, long id) {
                      String food = String.valueOf(parent.getItemAtPosition(position));
                      Toast.makeText(MovieShowings.this, food, Toast.LENGTH_LONG).show();
                  }
              }
      );
  }
  </code></pre>
  
  <p>}</p>
  
  <p>Error message</p>
  
  <p>FATAL EXCEPTION: main
                                                                                  Process: com.example.niallgrace.cinemaapp, PID: 6200
                                                                                  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.niallgrace.cinemaapp/com.example.niallgrace.cinemaapp.MovieShowings}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
                                                                                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
                                                                                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
                                                                                      at android.app.ActivityThread.-wrap11(Unknown Source:0)
                                                                                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
                                                                                      at android.os.Handler.dispatchMessage(Handler.java:105)
                                                                                      at android.os.Looper.loop(Looper.java:164)
                                                                                      at android.app.ActivityThread.main(ActivityThread.java:6541)
                                                                                      at java.lang.reflect.Method.invoke(Native Method)
                                                                                      at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
                                                                                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
                                                                                   Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
                                                                                      at com.example.niallgrace.cinemaapp.MovieShowings.onCreate(MovieShowings.java:22)
                                                                                      at android.app.Activity.performCreate(Activity.java:6975)
                                                                                      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
                                                                                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)</p>