从xampp下载数据库文件并使用SQLite保存在模拟器中

Question

我正在尝试用一个按钮更新AndroidStudio中的应用数据库。当您按下它时，程序会从xampp下载URL为http://IP:Port/user/bdcortes.db的文件“ bdcortes.db”，并覆盖以下路径中的现有文件：/data/data/com.example.user.app/databases/

自从数据库文件出现最后一个问题以来，我已修复了xampp中的一些错误，如ip和相应URL的端口。但是现在我有另一个问题。当我处理微调器中的数据时，我的程序无法正确读取数据库（一旦我在模拟器中有了新的db文件）。我不知道在完成下载文件或向另一个 TestAdapter 收费后，我是否必须停止Thread，我在其中对数据库文件进行所有查询。

谢谢！

public class Notas extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

    Spinner spinnerUni, spinnerGrad, spinnerAnio;
    TextView textView;
    Context myContext = this;
    ProgressDialog dialog;
    String fileDownloadPath = "http://localhost:4432/mario/bdcortes";
    String fileSavePath = "/data/data/com.example.mariorg.app/databases/";

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_notas);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);

        TestAdapter mDbHelper = new TestAdapter(this);
        mDbHelper.createDatabase();
        mDbHelper.open();

        dialog = null;

        // Inicialización de los elementos layout
        textView = findViewById(R.id.tvResultado);
        spinnerUni = findViewById(R.id.spUniversidad);
        spinnerGrad = findViewById(R.id.spGrado);
        spinnerAnio = findViewById(R.id.spAnio);

        spinnerUni.setOnItemSelectedListener(this);
        spinnerGrad.setOnItemSelectedListener(this);
        spinnerAnio.setOnItemSelectedListener(this);

        loadAllSpinners();

        spinnerUni.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                loadGrades(spinnerUni.getSelectedItem().toString(), spinnerAnio.getSelectedItem().toString());
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
    }

public void actualizar(View view){
        DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                switch (which){
                    case DialogInterface.BUTTON_POSITIVE:
                    //    dialog = ProgressDialog.show(Notas.this, "", "Actualizando...", true);
                        new Thread(new Runnable(){
                            @Override
                            public void run(){
                                downloadFile(fileDownloadPath, fileSavePath);
                            }
                        }).start();
                        break;

                    case DialogInterface.BUTTON_NEGATIVE:
                        Toast toast1 = Toast.makeText(getApplicationContext(), "ERROR AL DESCARGAR BD", Toast.LENGTH_SHORT);
                        toast1.show();
                        break;
                }
            }
        };

        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("Esto descargará los años previos a 2018. ¿Está seguro?").setPositiveButton("Sí", dialogClickListener)
                .setNegativeButton("No", dialogClickListener).show();

    }

    public void downloadFile(String fileDownloadPath, String fileSavePath){
        try{
            File saveFile = new File(fileSavePath);
            URL u = new URL(fileDownloadPath);
            URLConnection con = u.openConnection();// abrir conexion
            int lenghtofContent = con.getContentLength();

            DataInputStream DIStream = new DataInputStream(u.openStream());
            byte[] buffer = new byte[lenghtofContent];
            DIStream.readFully(buffer);
            DIStream.close();
            Log.e("HOLA", DIStream.toString());

            DataOutputStream DOStream = new DataOutputStream(new FileOutputStream(saveFile));
            DOStream.write(buffer);
            DOStream.flush();
            DOStream.close();

            Toast toast1 = Toast.makeText(Notas.this, "ACTUALIZADO", Toast.LENGTH_SHORT);
            toast1.show();

            //hideProgressIndicator();

        }catch (FileNotFoundException e){
            //hideProgressIndicator();
        }catch (IOException e){
            //hideProgressIndicator();
        }catch (Exception e){

        }
    }

    private void hideProgressIndicator() {

        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                dialog.dismiss();
            }
        });

    }

我已经测试了应用程序可以正确下载数据库文件，但是当您按下一个微调器时，不会在微调器中收费数据。