我设置了项目，以便点击地图并添加标记，我现在想尝试将该标记的坐标发送到下一个活动，我可以填写更多有关位置的详细信息发送我的数据库。如果有人可以提供任何帮助，我将非常感激。但是，每当我尝试将LatLn坐标发送到下一个活动时，我都会收到错误：
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.homescreen/com.homescreen.ClubForm}: java.lang.NullPointerException
继承我的代码，将标记添加到地图中，工作正常：
public class Map extends ActionBarActivity{
private GoogleMap myMap;
String c_name;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.map);
myMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
.getMap();
// Initializing
// Getting reference to Button
Button btnDraw = (Button) findViewById(R.id.btn_route);
Button btnAddClub = (Button) findViewById(R.id.btn_add_club);
btnDraw.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// if club button is pressed start ClubLogin Activity
Intent i = new Intent(getApplicationContext(), DrawRoute.class);
startActivity(i);
}
});
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
Location location = locationManager.getLastKnownLocation(locationManager.getBestProvider(criteria, false));
if (location != null)
{
myMap.setMyLocationEnabled(true);
myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(location.getLatitude(), location.getLongitude()), 13));
CameraPosition cameraPosition = new CameraPosition.Builder()
.target(new LatLng(location.getLatitude(), location.getLongitude())) // Sets the center of the map to location user
.zoom(6) // Sets the zoom
.bearing(0) // Sets the orientation of the camera to east
.tilt(40) // Sets the tilt of the camera to 30 degrees
.build(); // Creates a CameraPosition from the builder
myMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
}
btnAddClub.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
myMap.setOnMapClickListener(new OnMapClickListener() {
@Override
public void onMapClick(LatLng latlng) {
addMarker(latlng, c_name);
Intent c = new Intent(getApplicationContext(), ClubForm.class);
c.putExtra("latlng", latlng);
startActivity(c);
}
});
}
});
}
// Adding marker on the GoogleMaps
private void addMarker(LatLng latlng, String c_name) {
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latlng);
markerOptions.title(c_name);
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.club_marker));
myMap.addMarker(markerOptions);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
下面是我试图将latlng坐标发送到编辑文本框的表单的下一个活动：
public class ClubForm extends ActionBarActivity {
String c_name;
String c_email;
String c_address;
String c_phno;
String c_size;
InputStream is = null;
String result = null;
String line = null;
int code;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.club_form);
Bundle bundle = getIntent().getExtras();
if(bundle != null){
LatLng = new GeoPoint((int)(bundle.getDouble("lat") / 1E6),(int)(bundle.getDouble("long")/1E6));
animateToCurrentPoint(currentGeoPoint);
}
final EditText e_name = (EditText) findViewById(R.id.editbox2);
final EditText e_email = (EditText) findViewById(R.id.editbox7);
final EditText e_address = (EditText) findViewById(R.id.editbox3);
final EditText e_phno = (EditText) findViewById(R.id.editbox6);
final EditText e_size = (EditText) findViewById(R.id.editbox4);
final EditText e_latlng = (EditText) findViewById(R.id.editbox8);
Button submit = (Button) findViewById(R.id.btn_submit);
submit.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
c_name = e_name.getText().toString();
c_email = e_email.getText().toString();
c_address = e_address.getText().toString();
c_phno = e_phno.getText().toString();
c_size = e_size.getText().toString();
//latlng = e_latlng.getText().toString();
//submit();
}
});
}
/*public void submit() {
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("c_name", c_name));
nameValuePairs.add(new BasicNameValuePair("c_email", c_email));
nameValuePairs.add(new BasicNameValuePair("c_address", c_address));
nameValuePairs.add(new BasicNameValuePair("c_phno", c_phno));
nameValuePairs.add(new BasicNameValuePair("c_size", c_size));
nameValuePairs.add(new BasicNameValuePair("latlng", latlng));
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("purposely wrong");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
Log.e("pass 1", "connection success ");
} catch (Exception e) {
Log.e("Fail 1", e.toString());
Toast.makeText(getApplicationContext(), "Invalid IP Address",
Toast.LENGTH_LONG).show();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
Log.e("pass 2", "connection success ");
} catch (Exception e) {
Log.e("Fail 2", e.toString());
}
try {
JSONObject json_data = new JSONObject(result);
code = (json_data.getInt("code"));
if (code == 1) {
Toast.makeText(getBaseContext(), "Inserted Successfully",
Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getBaseContext(), "Sorry, Try Again",
Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
Log.e("Fail 3", e.toString());
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}*/
}
答案 0 :(得分：0)
下面
LatLng = new GeoPoint（（int）（bundle.getDouble（＆＃34; lat＆＃34;）/ 1E6），（INT）（bundle.getDouble（＆＃34;长＆＃34;）/ 1E6））;
NPE因为bundle不包含lat和long个密钥。
意图发送LatLng个对象。使用Intent.getParcelable来获取onCreate方法中的接收意图：
Intent intent = getIntent().getExtras();
if(intent !=null)
LatLng latlng = intent.getParcelable("latlng");