安卓传递变量到另一个Java文件

Question

如何传递latLongString到elhActivity并显示在屏幕上....这两个Java文件都是同一个包com.elh.whereami;

下这是whereami.java代码

package com.elh.whereami; 
    import android.app.Activity; 
    import android.content.Context; 
    import android.location.Criteria; 
    import android.location.Location; 
    import android.location.LocationListener; 
    import android.location.LocationManager; 
    import android.os.Bundle; 
    import android.widget.TextView; 

    public class whereami extends Activity { 

     @Override 
     public void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.main); 

      LocationManager locationManager; 
      String context = Context.LOCATION_SERVICE; 
      locationManager = (LocationManager) getSystemService(context); 

      Criteria criteria = new Criteria(); 
      criteria.setAccuracy(Criteria.ACCURACY_FINE); 
      criteria.setAltitudeRequired(false); 
      criteria.setBearingRequired(false); 
      criteria.setCostAllowed(true); 
      criteria.setPowerRequirement(Criteria.POWER_LOW); 
      String provider = locationManager.getBestProvider(criteria, true); 

      Location location = locationManager.getLastKnownLocation(provider); 
      updateWithNewLocation(location); 

      locationManager.requestLocationUpdates(provider, 2000, 10, locationListener); 
     } 

     private final LocationListener locationListener = new LocationListener() { 
      public void onLocationChanged(Location location) { 
       updateWithNewLocation(location); 
      } 

      public void onProviderDisabled(String provider) { 
       updateWithNewLocation(null); 
      } 

      public void onProviderEnabled(String provider) { 
      } 

      public void onStatusChanged(String provider, int status, Bundle extras) { 
      } 
     }; 

     public void updateWithNewLocation(Location location) { 
      String latLongString; 
      if (location != null) { 
       double lat = location.getLatitude(); 
       double lng = location.getLongitude(); 
       latLongString = "Lat:" + lat + "\nLong:" + lng; 
    } 
} 
} 

，这是elhActivity.java文件

package com.elh.whereami; 
import android.app.Activity; 
import android.widget.TextView; 

public class elhActivity extends Activity { 
    /** Called when the activity is first created. */ 
    public String Locationinfo = whereami.latLongString; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     TextView tv = new TextView(this); 
     tv.setText(Locationinfo); 
     setContentView(tv); 
} 
} 

Answer 1

首先，你必须从第一级开始elhActivity：

Intent intent = new Intent(this, elhActivity.class); 
intent.putExtra("the_latLongString", latLongString); 
startActivity(intent); 

然后，里面elhActivity你可以做这样的事情在onCreate方法：

String latLon = getIntent().getStringExtra("the_latLongString"); 
TextView tv = new TextView(this); 
tv.setText(latLon); 
setContentView(tv); 

Answer 2

Intent myintent=new Intent(Info.this, elhActivity.class).putExtra("latlon", value); startActivity(myintent);

获取数据
String s= getIntent().getStringExtra("latlong");

捆绑类可能会感兴趣

Answer 3

B如果使用putExtra和getExtars方法，则可以在两个活动之间传递数据。例如See this post。