Android TextView Timer aktualisieren und Karteninhalt aktualisieren?

Question

Ich habe die folgende Layoutdatei. Grundsätzlich habe ich Google Map und oben links habe ich eine TextView, wo ich Zähler alle 15 Sekunden sagen muss, um die Karte zu aktualisieren. Das Layout ist in Ordnung.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" > 

    <fragment xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    xmlns:map="http://schemas.android.com/apk/res-auto" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:id="@+id/map" 
    tools:context="com.example.ns.appversion1.MapActivityFragment1" 
    android:name="com.google.android.gms.maps.SupportMapFragment"/> 

    <FrameLayout 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_alignParentTop="true" > 

     <LinearLayout 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:orientation="vertical" 
      android:weightSum="2" > 

      <TextView 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_weight="1" 
       android:gravity="left" 
       android:padding="3dp" 
       android:id="@+id/textRefresh" 
       android:background="@drawable/border" 
       android:text="Refreshing 1" 
       android:textColor="#03A9FA" 
       android:textSize="12sp" /> 


     </LinearLayout> 
    </FrameLayout> 
</RelativeLayout> 

Unten sind meine Codes. In der View-Funktion versuche ich eine Handler Funktion zu implementieren um den Zähler zu halten. Daher möchte ich alle 15 Sekunden die Funktion JSON aufrufen, um die letzten lat-Werte abzurufen und entsprechend auf der Karte zu plotten. Ich bin jetzt im ersten Schritt hier stecken, wo es mir Fehler sagt, cant zugreifen Variable timeleft, m_handlerTask und m_handler von innerhalb der inneren Klasse? Ich möchte den Countdown anzeigen, damit der Benutzer in den nächsten 15 Sekunden weiß, dass die Karte aktualisiert wird?

public class MapActivityFragment1 extends Fragment implements OnMapReadyCallback { 
    private GoogleMap mMap; 
    TextView tv; 
    // TODO: Rename parameter arguments, choose names that match 
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER 
    private static final String ARG_PARAM1 = "param1"; 
    private static final String ARG_PARAM2 = "param2"; 

    // TODO: Rename and change types of parameters 
    private String mParam1; 
    private String mParam2; 

    private OnFragmentInteractionListener mListener; 

    public MapActivityFragment1() { 
     // Required empty public constructor 
    } 

    // TODO: Rename and change types and number of parameters 
    public static MapActivityFragment1 newInstance(String param1, String param2) { 
     MapActivityFragment1 fragment = new MapActivityFragment1(); 
     Bundle args = new Bundle(); 
     args.putString(ARG_PARAM1, param1); 
     args.putString(ARG_PARAM2, param2); 
     fragment.setArguments(args); 
     return fragment; 
    } 
    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
     View view = inflater.inflate(R.layout.fragment_map_activity_fragment1, null, false); 

     SupportMapFragment mapFragment = (SupportMapFragment) this.getChildFragmentManager() 
       .findFragmentById(R.id.map); 
     mapFragment.getMapAsync(this); 
     tv = (TextView) getActivity().findViewById(R.id.textRefresh); 
     Handler m_handler; 
     Runnable m_handlerTask ; 
     final int timeleft=15000; 
     final m_handler = new Handler(); 
     final m_handlerTask = new Runnable() 
     { 
      @Override 
      public void run() { 
       if(timeleft>=0) 
       { 
        // do stuff 
        Log.i("timeleft",""+timeleft); 
        timeleft--; 
        tv.setText("Refreshing in "+timeleft); 

       } 
       else 
       { 
        m_handler.removeCallbacks(m_handlerTask); // cancel run 
       } 
       m_handler.postDelayed(m_handlerTask, 1000); 
      } 
     }; 
     m_handlerTask.run(); 

     return view; 
    } 
    @Override 
    public void onMapReady(GoogleMap googleMap) { 
     mMap = googleMap; 
     // Add a marker in Sydney and move the camera 
     LatLng sydney = new LatLng(-34, 151); 
     mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney")); 
     mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney)); 
    } 

    // TODO: Rename method, update argument and hook method into UI event 
    public void onButtonPressed(Uri uri) { 
     if (mListener != null) { 
      mListener.onFragmentInteraction(uri); 
     } 
    } 


    public void onAttach(Context context) { 
     super.onAttach(context); 
    } 

    @Override 
    public void onDetach() { 
     super.onDetach(); 
     mListener = null; 
    } 

    public interface OnFragmentInteractionListener { 
     // TODO: Update argument type and name 
     void onFragmentInteraction(Uri uri); 
    } 
} 

Ich habe Charus Lösung wie folgt versucht.

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
     View view = inflater.inflate(R.layout.fragment_map_activity_fragment1, null, false); 

     SupportMapFragment mapFragment = (SupportMapFragment) this.getChildFragmentManager() 
       .findFragmentById(R.id.map); 
     mapFragment.getMapAsync(this); 
     tv = (TextView) getActivity().findViewById(R.id.textRefresh); 
     MyCount counter = new MyCount(15000, 1000); 
     counter.start(); 

     return view; 
    } 

Answer 1

Dies wird einen Countdown von 15 bis 0 (-1 pro Sekunde) demonstrieren, und diese Aufgabe wird alle 15 Sekunden wiederholt!

public class YourActivity extends Activity { 


    TextView textView; 
    android.os.Handler customHandler; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 

     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_home); 
     textView = (TextView) findViewById(R.id.text); 


     customHandler = new android.os.Handler(); 
     customHandler.postDelayed(updateTimerThread, 0); 
    } 


    // count down timer is an abstract class, so extend it and fill in methods 
    public class MyCount extends CountDownTimer { 

     public MyCount(long millisInFuture, long countDownInterval) { 
      super(millisInFuture, countDownInterval); 
     } 

     @Override 
     public void onFinish() { 
      textView.setText("done!"); 
     } 

     @Override 
     public void onTick(long millisUntilFinished) { 
      textView.setText("Left: " + millisUntilFinished/1000); 
     } 
    } 

    private Runnable updateTimerThread = new Runnable() 
    { 
     public void run() 
     { 

      // 10000 is the starting number (in milliseconds) 
      // 1000 is the number to count down each time (in milliseconds) 
      MyCount counter = new MyCount(15000, 1000); 
      counter.start(); 
      customHandler.postDelayed(this, 15000); // repeat body after 15 seconds 
     } 
    }; 
}