title: Update fragment from activity
body: <p>I do not understand how can I transfer data from fragmentactivity to fragment, i have:</p>
  
  <p>MainScreen.class</p>
  
  <pre><code>public class MainScreen extends FragmentActivity {
  CollectionPagerAdapter mCollectionPagerAdapter;
  ViewPager mViewPager;
  
  public static String currentCityId;
  
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.tabs_collection);
  
      mCollectionPagerAdapter = new CollectionPagerAdapter(getSupportFragmentManager());
  
      final ActionBar actionBar = getActionBar();
  
      actionBar.setDisplayHomeAsUpEnabled(false);
      actionBar.setTitle(getString(R.string.app_name));
      actionBar.setIcon(R.drawable.device_access_brightness_high);
  
      mViewPager = (ViewPager) findViewById(R.id.pager);
      mViewPager.setAdapter(mCollectionPagerAdapter);
  }
  
  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
      MenuInflater inflater = getMenuInflater();
      inflater.inflate(R.menu.mainmenu, menu);
      return true;
  }
  
  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
      switch (item.getItemId()) {
          case R.id.action_refresh:
              Log.w("Refresh", "refresh");
  
              break;
          case R.id.action_options:
  
              break;
          case R.id.submenu_about:
  
              break;
          case R.id.submenu_help:
  
              break;
          case R.id.submenu_buy:
  
              break;
          case R.id.submenu_settings:
  
              break;
          case R.id.submenu_share:
  
              break;
          default:
              break;
      }
  
      return true;
  }
  
  public class CollectionPagerAdapter extends FragmentStatePagerAdapter {
      FragmentManager fm;
  
      public CollectionPagerAdapter(FragmentManager fm) {
          super(fm);
          this.fm = fm;
      }
  
      @Override
      public Fragment getItem(int position) {
          switch (position) {
              case 0:
                  return new FragmentDay();
              case 1:
                  return new FragmentHour();
              case 2:
                  return new FragmentDaily();
              default:
                  return new FragmentDay();
          }
      }
  
      @Override
      public int getCount() {
          return 3;
      }
  
      @Override
      public CharSequence getPageTitle(int position) {
          switch (position) {
              case 0:
                  return getString(R.string.tab_day);
              case 1:
                  return getString(R.string.tab_hour);
              case 2:
                  return getString(R.string.tab_daily);
              default:
                  return getString(R.string.tab_day);
          }
      }
  }
  </code></pre>
  
  <p>FragmentDay.class</p>
  
  <pre><code>public class FragmentDay extends Fragment {
  TextView currentTemp;
  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
      View rootView = inflater.inflate(R.layout.hour_screen, container, false);
      Bundle args = getArguments();
      currentTemp = (TextView)rootView.findViewById(R.id.day_current_temp);
      return rootView;
  }
  </code></pre>
  
  <p>}</p>
  
  <p>main.xml</p>
  
  <pre><code>&lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
              android:layout_height="match_parent"
              android:layout_width="match_parent"
              android:background="@drawable/bk_new"&gt;
  
  &lt;android.support.v4.view.ViewPager
          android:id="@+id/pager"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"&gt;
  
      &lt;android.support.v4.view.PagerTitleStrip
              android:id="@+id/pager_title_strip"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:layout_gravity="top"
              android:background="#33b5e5"
              android:textColor="#fff"
              android:paddingTop="4dp"
              android:paddingBottom="4dp"/&gt;
  &lt;/android.support.v4.view.ViewPager&gt;
  </code></pre>
  
  <p></p>
  
  <p>and fragment.xml:</p>
  
  <pre><code>&lt;RelativeLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/dayScreen"
      android:orientation="vertical"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="@drawable/bk_new"&gt;
  
  &lt;TextView
          android:id="@+id/day_current_temp"
          android:layout_height="wrap_content"
          android:layout_width="wrap_content"
          android:layout_centerHorizontal="true"
          android:text="22 C"
          android:textColor="#FFFFFF"
          android:textSize="38dp"
          android:layout_marginTop="270dp"/&gt;
  </code></pre>
  
  <p></p>
  
  <p>Read these articles (<a href="https://stackoverflow.com/questions/8956803/viewpager-activity-to-notify-a-fragment-of-a-specific-event">ViewPager Activity to notify a Fragment of a specific event</a>, <a href="https://stackoverflow.com/questions/12341591/updating-fragments-from-activity-in-a-viewpager">Updating fragments from Activity in a ViewPager</a>, <a href="https://stackoverflow.com/questions/15662721/viewpager-update-fragment-from-activity">ViewPager - Update fragment from activity</a>) and do not understand what to do!
  I will be very grateful for the help!</p>