I am trying to calculate the distance between the first GPS point stored in a SQLite database and the last GPs point stored.
My code so far is this:
private double Distance()
{
SQLiteDatabase db1 = waypoints.getWritableDatab开发者_StackOverflow社区ase();
Cursor cursor = db1.query(TABLE_NAME, FROM, null, null, null, null,ORDER_BY);
Cursor cursor1 = db1.query(TABLE_NAME, FROM, null, null, null, null,ORDER_BY);
Double lat = cursor.getDouble(2);
Double lon = cursor.getDouble(1);
cursor.moveToFirst();
cursor.moveToLast();
cursor.close();
distance = cursor.distanceTo(cursor1);
}
I realise I need to return a value but the error I am receiving is for the distanceTo
method:
"The method distanceTo(Cursor) is undefined for the type Cursor
As the error message says, the method distanceTo()
doesn't exist on the type Cursor: https://developer.android.com/reference/android/database/Cursor.html
The method distanceTo(Location)
is available on the Location class:
https://developer.android.com/reference/android/location/Location.html
You'll need to create Location objects from your longitude/latitude values in your DB before you attempt to call distanceTo()
.
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