Android Programming

Go back to Android Interface

Knowing general Android programming can be very useful to help developing the Lazarus Android Interface.

Creating a new Java Android Application

See here: http://developer.android.com/guide/developing/other-ide.html

Android API Hello World in Pascal

Here is an example Pascal application written for Android.

<delphi> program pascalnotes4android;

{$mode objfpc}{$H+}

uses

 Classes, androidpipescomm, androidui, javalang;

{$R *.res}

var

 layout: TAbsoluteLayout;
 params: TAbsoluteLayout_LayoutParams;
 tv: TTextView;
 et: TTextView;
 btn: TButton;

begin

 // Here add any initialization.
 // Any initialization code will be run inside Activity.onCreate,
 // so keep it as short as possible!
 // It should mostly contain GUI initialization
 // User interface

 // Prepares the UI of the program
 layout := TAbsoluteLayout.Create;

 tv := TTextView.Create;
 tv.setText('The first Pascal Android application =)');
 params := TAbsoluteLayout_LayoutParams.Create(320, 300, 0, 120);
 layout.addView(tv, params);
 params.Free;

 et := TEditText.Create;
 et.setText('edit me please');
 params := TAbsoluteLayout_LayoutParams.Create(320, 50, 0, 0);
 layout.addView(et, params);
 params.Free;

 btn := TButton.Create;
 btn.setText('Go!');

{ btn.setOnClickListener(buttonClickCallback);}

 params := TAbsoluteLayout_LayoutParams.Create(320, 50, 0, 60);
 layout.addView(btn, params);
 params.Free;

 Activity.setContentView(layout);

 // Now tell Java that the initialization has finished
 myAndroidPipesComm := TAndroidPipesComm.Create;
 myAndroidPipesComm.InitializationFinished();
 // Here you can add any other initialization,
 // specially non-GUI code

 // Now we block our execution waiting for callbacks from Java
 myAndroidPipesComm.MessageLoop();

end. </delphi>

Compiling the example project in Linux

1> Get a working arm-linux cross-compiler which generates ARMv5 eabi with softfloat (as many phones like HTC Wildfire have no FPU)

To do this one can download an unofficial build from here:

http://members.yline.com/~tom_at_work/fpc-2.4.2.UNOFFICIAL.arm-linux.tar . Again ARMv5 eabi with softfloat.

Or build your own.

2> Install the Android SDK

3> Install ant, for example:

urpmi ant

4> Open the project PascalNotes4Android/pascalsrc/pascalnotes4android.lpi in Lazarus and build it's build mode Android

5> Copy the generate executable

 cp pascalsrc/pascalnotes4android libs/armeabi/libpascalnotes4android.so 

if the directory libs/armeabi doesn't exist, create it

6> Build the APK file in debug mode

 ant debug

7> Connect your phone and make sure you can connect to it via ADB

8> Install the APK file in your phone via ADB or whatever other method you prefer:

 ../android-sdk-linux_x86/tools/adb install bin/PascalNotes4Android-debug.apk

If the package is already installed you need need to do this instead:

 ../android-sdk-linux_x86/tools/adb uninstall com.pascalnotes
 ../android-sdk-linux_x86/tools/adb install bin/PascalNotes4Android-debug.apk

References

• http://developer.android.com/guide/developing/other-ide.html