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Mobile Tutorial: Using InterBase ToGo with FireDAC (iOS and Android)

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Go Up to Mobile Tutorials: Mobile Application Development (iOS and Android)


Before starting this tutorial, you should read and perform the following tutorial session:

Tip: Following this tutorial requires a license for IBToGo or IBLite:

  • If you purchased one of the following Appmethod versions, you have received in Email a key for an unlimited development and deployment license for IBLite:
    • Appmethod XE5 Professional or higher
    • Object Pascal XE5 Professional with Mobile or higher
  • If you are a trial user, your installation includes a trial license for IBToGo. You can test InterBase on iOS and Android by selecting your test license during the deployment step, as described in this tutorial. The trial licenses are installed with your trial product, in PublicInterBaseXE3Path
Note: On Android devices, InterBase ToGo apps require specific Uses Permissions to be set, specifically:
  • Read external storage (the database is placed in the external memory)
  • Write external storage (the database is placed in the external memory)
  • Internet (you need to connect with a remote server)

This tutorial describes the basic steps to browse data managed by InterBase ToGo on your iOS and Android devices through the FireDAC framework.

iOS Android

DBDemo iPod Runtime.png

DBDemo Runtime.png

Note: You can use FireDAC, dbExpress, and Interbase Express (IBX) components to build Interbase ToGo applications. For a detailed discussion on Interbase Express components usage in a Object Pascal application, read the Getting Started with InterBase Express article. For this tutorial, we will connect to Interbase ToGo using dbExpress framework.

Using FireDAC to Connect to the Database

FireDAC is a unique set of Universal Data Access Components for developing cross-platform database applications for Object Pascal and C++. With its powerful common architecture, FireDAC enables native high-speed direct access from Object Pascal to InterBase, SQLite, MySQL, SQL Server, Oracle, PostgreSQL, IBM DB2, SQL Anywhere, Access, Firebird, Informix, and more.

  • For the mobile platforms, FireDAC supports InterBase ToGo as well as SQLite. These database products can run on iOS and Android devices.
  • For other databases, such as Oracle, you need to have at least a client library. On Windows platforms, the client library is provided as a DLL to connect to. Therefore, you need to develop applications using middle-tier technologies such as DataSnap to connect to these database products from a mobile device.
Another tutorial discusses how to connect to Enterprise Database without using a client library on a mobile device; see Mobile Tutorial: Connecting to an Enterprise Database from a Mobile Client (iOS and Android).

Design and Set Up the User Interface

This tutorial uses TListView and TPanel components as the UI elements.

To set up a ListView and a Panel component, use the following steps:

  1. To create an HD FireMonkey Mobile Application, select either of the following:
    • File > New > FireMonkey Mobile Application - Object Pascal > Blank Application
    • File > New > FireMonkey Mobile Application - C++ > Blank Application
  2. Drop a TListView component on the form.
  3. In the Object Inspector, set the following properties of the ListView:
    • Set the Align property to Client, so that the ListView component uses the entire form.
    • Set the ItemAppearance to ListItemRightDetail.
    • Set the SearchVisible to true.
  4. Add a TPanel component to the form, and set the following properties in the Object Inspector:
    • Set the Align property for the TPanel component to Top.
  5. Add a TLabel component to the Panel, and set the following properties in the Object Inspector:

Connecting to the Data

Following are the basic steps to connect to data in a database using FireDAC:

  1. On the Tool Palette, double-click the TFDConnection component.
    FDConnectionComp.png
  2. Right-click the TFDConnection component and choose Connection Editor.
  3. In the FireDAC Connection Editor, set the following parameters of the TFDConnection:
    1. Set the Driver ID property to IB.
    2. Set the Database parameter to:
      C:\Users\Public\Documents\Embarcadero\Studio\14.0\Samples\Data\dbdemos.gdb (location of the database)
      and click Open in the File Open dialog box.
    3. Set the User_name parameter to sysdba.
    4. Set the Password parameter to masterkey.
      FDConnectionEditor.png

    5. Click the Test button to test the connection.
    6. Click OK to close the Connection Editor.
  4. In the Object Inspector, set the following properties of TFDConnection:
    1. Set the LoginPrompt property to False, so that the user is not prompted for a login.
    2. Set the Connected property to True.
      Note: If you get an error ("unavailable database") in the development environment, this means you do not have a current license for InterBase. The license of InterBase Developer Edition is included as part of the product for some product editions. For more information, see Troubleshooting.
  5. Add a TFDQuery component to the form.
  6. Right-click the TFDQuery component and choose Query Editor.
    1. Write in the SQL Command Text editor select COMMON_NAME, SPECIES_NAME from BIOLIFE order by COMMON_NAME.
    2. Click the Execute button to see the command results.
      FDQueryCommandDBDemo.png

    3. Click OK to close the Query Editor.
  7. In the Object Inspector, set the Active property of the TFDQuery component to True.
  8. Open the LiveBindings Designer and connect the data and the user interface as follows:
    1. Click COMMON_NAME in FDQuery1, and drag the mouse cursor to Item.Text in ListView1.
      LiveBindingsDesignerCommon Name.png

      At this point, TBindSourceDB and TBindingsList components were added to the form.
    2. Click SPECIES_NAME in BindSourceDB1, and drag the mouse cursor to Item.Detail in ListView1.
      DBDemoDesignTime.png
  9. Add a TFDPhysIBDriverLink component to the form.
  10. Add a TFDGUIxWaitCursor component to the form.
Note: The Preparing a FireDAC Application for Run Time topic explains the use of the TFDGUIxWaitCursor and TFDPhysIBDriverLink components in a FireDAC application.

Deploying your Application to Mobile

Up to this point, you have used InterBase on your desktop. This means that the actual database is located at your local hard disk drive (for example, C:\Users\Public\Documents\Embarcadero\Studio\14.0\Samples\Data\dbdemos.gdb). On the mobile Device, the application is sand-boxed, and typically you can only read and write data that is located in the Documents folder (for iOS device) and internal storage (for Android device) under your application folder.

To connect to a local database on mobile, you need to perform the following actions:

  • Deploy the database to the mobile device.
  • Change the configuration (to connect to the database file) to a local file under the Documents folder (for iOS device) or internal storage (for Android device).

Deploying InterBase ToGo and the Database File to Mobile

To execute your application on mobile, you need to deploy the following files:

  • Interbase ToGo
  • The database file (dbdemos.gdb)
  1. Open the Deployment Manager by selecting Project > Deployment.
  2. Select All-Configurations - iOS Device platform or All-Configurations - Android platform from the drop-down list of target platforms at the top of the Deployment Manager.
  3. Select Add Featured Files (DMgrAddFeatFiles.png):
    AddingFeaturedFiles.png

  4. Select the following database modules, and then click OK to close the Featured Files dialog box:
    • InterBase ToGo. You need to select the license to be used when deploying the application on the device.
      • The Tip at the beginning of this tutorial describes how to activate an InterBase license.
      • The suggested names for the license files available are listed in the Featured Files dialog, under the following name pattern: reg_*.txt.
        As you can see in the image below, the reg_ibtogo.txt license file is selected for this tutorial.
      • You might have received from Embarcadero a license file for IBToGo or IBLite that has a pattern of reg_nnnnnnn.txt, where nnnnnnn is a generated number:
        • If you have saved that file over reg_ibtogo.txt or reg_iblite.txt in the location below (for example, C:\Users\Public\Documents\Embarcadero\InterBase\redist\InterBaseXE3), you can just select the desired license.
        • If you have saved the file with its original name, then select Add Files (shown in the next step) and include the license file in the list of files that need to be deployed with the application.
    FeaturedFilesiOSAndroidDB.png

  5. Select Add Files and select the database file (for example, C:\Users\Public\Documents\Embarcadero\Studio\14.0\Samples\Data\dbdemos.gdb).
    AddingDatabaseFile.png

  6. Select dbdemos.gdb and change Remote Path to StartUp\Documents\ (for iOS platform) or assets\internal\ (for Android platform).
    RemotePath on iOS device platform
    ChangeToStartUpDocuments.png

    RemotePath on Android platform
    AddDBforAndroidAssets.png

  7. Select the Platforms column (double-click the ellipsis [...] in the row for dbdemos.gdb):
    1. Ensure that iOS Simulator and iOS Device or Android are present for dbdemos.gdb.
    2. Remove Win32 from the list if it is present (you do not have to copy database files to the Win32 platform).
  8. Select All-Configurations - iOS Device platform or All-Configurations - Android platform, and make sure dbdemos.gdb is set to be deployed to StartUp\Documents\ or assets\internal.

As you just configured, when you run the app on the mobile device, the database file (dbdemos.gdb) is to be deployed to the Documents folder (for iOS platform) or internal storage (for Android platform) in the sandbox area of your mobile app.

Object Pascal:

procedure TForm1.FDConnection1BeforeConnect(Sender: TObject);
begin
  {$IF DEFINED(iOS) or DEFINED(ANDROID)}
   FDConnection1.Params.Values['Database'] := 
      TPath.Combine(TPath.GetDocumentsPath, 'dbdemos.gdb');
  {$ENDIF}
end;

The TPath record is declared in System.IOUtils unit, so you need to add System.IOUtils in the uses clause.

C++:

void __fastcall TForm1::SQLConnection1BeforeConnect(TObject *Sender)
{
  #if ((defined(__arm__) && defined(__APPLE__)) || defined(__ANDROID__))
      FDConnection1->Params->Values["Database"] =
          System::Ioutils::TPath::Combine(System::Ioutils::TPath::GetDocumentsPath(), "dbdemos.gdb");
  #endif
}

You need to add #include <System.IOUtils.hpp>.

Run Your Application on a Simulator or on a Mobile Device

Now your application is ready to run. You should be able to browse data just as you can in the IDE. You can narrow down the list using the Search Box.

iOS Android

IPodSearchDBDemo.png

Screenshot 2013-11-02-03-34-10.png

Troubleshooting

InterBase License Issues

If you get an error ("unavailabale database") when you connect to the database in the development environment, this means you forgot to deploy the Interbase ToGo license.

  • To execute your application on mobile, deploy the reg_ibtogo.txt or reg_iblite.txt license files.
  • The license files are located in PublicInterBaseXE3Path directory.

Exception Handling Issues

If your application raises an exception without having proper exception handling code, your mobile app simply crashes (disappears) at run time.

If you encounter a crash, you might want to connect manually to the database while you troubleshoot the issue using the following steps:
  1. Select the FDConnection1 component, and change the Connected property to False.
  2. Drop a button on the form, and create the following event handler to manually connect to the database:

Object Pascal:

procedure TForm1.Button1Click(Sender: TObject);
begin
  try
    FDConnection1.Connected := True;
    FDQuery1.Active := True;
  except
    on e: Exception do
    begin
      ShowMessage(e.Message);
    end;
  end;
end;

C++:

void __fastcall TForm1::Button1Click(TObject *Sender) {
    try {
        FDConnection1->Connected = true;
        FDQuery1->Active = true;
    }
    catch(Exception &e) {
        ShowMessage(e.Message);
    }
}

Typical Errors and Resolutions

Following are typical errors that you might encounter when you connect to the database, and suggestions for resolving the issues:

Error on mobile Suggestion
GDBFileNotFound.PNG Check whether the dataBase file (dbdemos.gdb) is delivered to 'StartUp\Documents\' (for iOS) or 'assets\internal\' (for Android).
LicenseIssueFD.png Check whether the license file is delivered for InterBase ToGo.
NeedToPointLocalFile.PNG Check whether you pointed to the local file (add an event handler for the OnBeforeConnect event of the FDConnection1 component).

See Also

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