使用Delphi FireMonkey将SQLite数据库部署到Android

Question

I am trying to deploy an application to run on the android emulator using delphi that uses an SQLite database and populates a combobox with the query results.

I Have tested all the code on a Win32 application and everything is working as intended, however when i deploy the SQLite database and try to run the application on the emulator i raise an exception with "TDBXError with message" and the ErrorMessage contains 'no such table: cars'

Below is the code for my form.

    var
  Form1: TForm1;

implementation

{$R *.fmx}

procedure TForm1.Button1Click(Sender: TObject);
begin
  // Populate Manufacturer box
  SQLConnection1.Connected := True;
  SQLQuery1.SQL.Clear;
  SQLQuery1.Close;
  SQLQuery1.SQL.Add('SELECT DISTINCT manufacturer FROM cars');
  try
    SQLQuery1.Open;
    cbManufac.Items.Clear;
    while not SQLQuery1.Eof do
    begin
      cbManufac.Items.Add(SQLQuery1.Fields[0].AsString);
      SQLQuery1.Next;
    end;
  finally
    SQLQuery1.Close;
  end;
end;

procedure TForm1.SQLConnection1BeforeConnect(Sender: TObject);
begin
  {$IF DEFINED(iOS) or DEFINED(ANDROID)}
  SQLConnection1.Params.Values['ColumnMetadataSupported'] := 'False';
  SQLConnection1.Params.Values['Database'] :=
      System.IOUtils.TPath.Combine(TPath.GetDocumentsPath, 'cars.sqlite');
  {$ENDIF}
end;

end.

I Have made sure System.IOUtils is added to uses and my database file is added under my projects deployment settings.

If i activate Win32 and test the application the combobox entries are added just fine.

On the form designer i am using TSQLConnection and TSQLQuery

Can anybody point me in the right direction.

Thanks

Answer 1

In the Deployment Manager, set your remote path for your database to assets\\external . (See the documentation here for the difference between assets\\internal and assets\\external .)

Change your BeforeConnect event code to:

procedure TForm1.SQLConnection1BeforeConnect(Sender: TObject);
begin
  {$IF DEFINED(iOS) or DEFINED(ANDROID)}
  SQLConnection1.Params.Values['ColumnMetadataSupported'] := 'False';
  SQLConnection1.Params.Values['Database'] :=
      TPath.Combine(TPath.GetSharedDocumentsPath, 'cars.sqlite');
  {$ENDIF}
end;

To see the physical location of TPath.GetSharedDocumentsPath and other locations, see Standard RTL Path Functions Across the Supported Target Platforms .