Android Google地图使用存储的Sqlite数据库添加标记

当我在Autocompletetextview中键入“Fair”时，我的应用程序停止

当我在Autocompletetextview中键入nothing（即空）时，它会显示我存储在sqlite中的地图中的所有位置

当我在Autocompletetextview中键入“优秀”时。它只显示了地图上的“最佳”位置

但是，当我在Autocompletetextview中键入“Fair”时。它不存储在sqlite中的任何位置。它停止了我的应用程序。我希望它显示“数据不可用”，而不是停止我的应用程序。如何更改我的以下代码

错误是：

Process: com.example.bharat.plantnow, PID: 15807
android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
        at android.database.AbstractCursor.checkPosition(AbstractCursor.java:426)
        at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:136)
        at android.database.AbstractWindowedCursor.getDouble(AbstractWindowedCursor.java:86)
        at com.example.bharat.plantnow.MapsActivity$1.onClick(MapsActivity.java:149)

我的SQLITE数据库列包括：

    //Table Columns names
private static final String KEY_TID = "id";
public static final String KEY_TreeID = "treeid";
public static final String KEY_TCONDITION = "condition";
public static final String KEY_TLATITUDE = "latitude";
public static final String KEY_TLONGITUDE = "longitude";

我的sqlite数据库：我存储了“优秀”和“良好”的值。不存储“公平”的任何值

我的地图活动：

 btMap.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String search = inputSearch.getText().toString();

            if(search.equals("")) {
                double latitude = 0;
                double longitude = 0;
                String mark;

                // SQLite database handler
                db = new TreeData(getApplicationContext());



                Cursor locationCursor = db.getLocations();

                locationCursor.moveToFirst();

                do {
                    latitude = locationCursor.getDouble(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TLATITUDE));
                    longitude = locationCursor.getDouble(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TLONGITUDE));

                    mark = locationCursor.getString(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TreeID));

                    LatLng location = new LatLng(latitude, longitude);

                    mMap.addMarker(new MarkerOptions().position(location).title(mark));


                } while (locationCursor.moveToNext());

            }


            if(search.length()>0){

                //float zoom = 0;
                mMap.clear();

                // SQLite database handler
                db = new TreeData(getApplicationContext());


                Cursor c = db.getSelectedLocations(search);


                c.moveToFirst();

                do {

                   double latitude1 = c.getDouble(c
                            .getColumnIndex(SQLiteHandler.KEY_TLATITUDE));
                    double longitude1 = c.getDouble(c
                            .getColumnIndex(SQLiteHandler.KEY_TLONGITUDE));

                    String marker = c.getString(c
                            .getColumnIndex(SQLiteHandler.KEY_TreeID));

                    LatLng location = new LatLng(latitude1, longitude1);

                    mMap.addMarker(new MarkerOptions().position(location).title(marker));

                    // Moving CameraPosition to last clicked position
                    mMap.moveCamera(CameraUpdateFactory.newLatLng(location));

                    // Setting the zoom level in the map on last position is clicked
                     mMap.animateCamera(CameraUpdateFactory.newLatLng(location));


                } while (c.moveToNext());
                Toast.makeText(getApplicationContext(), "All is Well", Toast.LENGTH_LONG).show();
        }
            else{

                Toast.makeText(getApplicationContext(), "Invalid", Toast.LENGTH_LONG).show();
            }
    }
});}

---

您有一个emtpy光标。不要检查它是否为null，而是尝试检查（mCursor.getCount（）>0）{//do stuff}谢谢Sasikumar。现在它的工作很好。。

 btMap.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String search = inputSearch.getText().toString();

            if(search.equals("")) {
                double latitude = 0;
                double longitude = 0;
                String mark;

                // SQLite database handler
                db = new TreeData(getApplicationContext());



                Cursor locationCursor = db.getLocations();

                locationCursor.moveToFirst();

                do {
                    latitude = locationCursor.getDouble(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TLATITUDE));
                    longitude = locationCursor.getDouble(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TLONGITUDE));

                    mark = locationCursor.getString(locationCursor
                            .getColumnIndex(SQLiteHandler.KEY_TreeID));

                    LatLng location = new LatLng(latitude, longitude);

                    mMap.addMarker(new MarkerOptions().position(location).title(mark));


                } while (locationCursor.moveToNext());

            }


            if(search.length()>0){

                //float zoom = 0;
                mMap.clear();

                // SQLite database handler
                db = new TreeData(getApplicationContext());


                Cursor c = db.getSelectedLocations(search);


                c.moveToFirst();

                do {

                   double latitude1 = c.getDouble(c
                            .getColumnIndex(SQLiteHandler.KEY_TLATITUDE));
                    double longitude1 = c.getDouble(c
                            .getColumnIndex(SQLiteHandler.KEY_TLONGITUDE));

                    String marker = c.getString(c
                            .getColumnIndex(SQLiteHandler.KEY_TreeID));

                    LatLng location = new LatLng(latitude1, longitude1);

                    mMap.addMarker(new MarkerOptions().position(location).title(marker));

                    // Moving CameraPosition to last clicked position
                    mMap.moveCamera(CameraUpdateFactory.newLatLng(location));

                    // Setting the zoom level in the map on last position is clicked
                     mMap.animateCamera(CameraUpdateFactory.newLatLng(location));


                } while (c.moveToNext());
                Toast.makeText(getApplicationContext(), "All is Well", Toast.LENGTH_LONG).show();
        }
            else{

                Toast.makeText(getApplicationContext(), "Invalid", Toast.LENGTH_LONG).show();
            }
    }
});}