Question

你好我在这里遇到问题

我有一个用于我的观点数据库的添加和编辑表单它有两个用于坐标的EditText，用于经度和纬度它有一个按钮来获取当前坐标如果我单击按钮，两个EditTexts填充坐标并且用户可以继续插入或编辑数据

我的代码返回java.nullPointerException，我不知道为什么......

这是我的代码：

btn_getkoor.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                try{

                    LocationListener gpsLocation = new MyLocationListener();
                    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, gpsLocation); //new MyLocationListener());
                    Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);

                    final TextView error_text = (TextView) findViewById(R.id.error_text);

                    if (location != null) {

                        EditText et_longitude = (EditText) findViewById(R.id.et_longitude);
                        EditText et_latitude = (EditText) findViewById(R.id.et_latitude);

                        et_longitude.setText(""+location.getLongitude());   // longitude textview
                        et_latitude.setText(""+location.getLatitude());     //latitude textview

                        locationManager.removeUpdates((LocationListener) location);
                        locationManager = null;

                    }else{
                        toastkeun("Terjadi Kesalahan dalam pengambilan koordinat");             //toast function
                        error_text.setText("Terjadi Kesalahan dalam pengambilan koordinat");    //textview for showing errors
                    }
                }catch(Exception e){
                    toastkeun(e.toString());
                }

            }
        });

任何解决方案？

我已经设置了清单文件FYI

Answer 1

很难从您的代码中说出：如果您还没有这样做，请输入以下代码：

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

Answer 2

     LocationManager locationManager;
    String bestProvider;
    String LOCATION_SERVICE="location" ; 
    locationManager = (LocationManager) this.getSystemService(LOCATION_SERVICE);
        Criteria criteria = new Criteria();
        //criteria.setAccuracy();
        criteria.setAccuracy(Criteria.ACCURACY_FINE);  // More accurate, GPS fix.
        bestProvider = locationManager.getBestProvider(criteria,true);
    location location = locationManager.getLastKnownLocation(bestProvider);
if (location != null) {

                        EditText et_longitude = (EditText) findViewById(R.id.et_longitude);
                        EditText et_latitude = (EditText) findViewById(R.id.et_latitude);

                        et_longitude.setText(""+location.getLongitude());   // longitude textview
                        et_latitude.setText(""+location.getLatitude());     //latitude textview

                       // locationManager.removeUpdates((LocationListener) location);
                        locationManager = null;

                    }else{
                        toastkeun("Terjadi Kesalahan dalam pengambilan koordinat");             //toast function
                        error_text.setText("Terjadi Kesalahan dalam pengambilan koordinat");    //textview for showing errors
                    }

如何通过单击按钮获取用户的GPS坐标？

2 个答案: