In this post, I will write on one of the ways/methods of porting JavaFX application to Android. If you have a good idea about this topic, feel free to drop some points.

To accomplish this goal, you will need the following:

- Java 7 or 8 SDK (JDK7 or JDK8)
- Android SDK
- JavaFX Dalvik SDK
- Gradle
- Ant
- Visual Studio Code
- Android Phone

my other account was just banned now.

- Download JDK 7 or 8 from oracle website and install.
Add it to your Environment Variables.

- Download Android Studio IDE, Android SDK comes with it
Add the Android Studio SDK path to your Environment Variables.
Add the Android Studio SDK/tools path to your Environment Variables.

-Download JavaFX Dalvik SDK and unpack the Zip file to a good location on your system, preferrably under C:/

- Download Gradle and unpack the Zip file to good location
add the path to your Enivironment Variables.

- Download ant and unzip to a good location
add the path to your Enivironment Variables.

Run this commands to verify if everything is ok

-Create a Simple JavaFX application:

package fxandroid;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextArea;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.text.Text;
import javafx.stage.Stage;

/**
*
* @author STEINACOZ-PC
*/
public class FXAndroid extends Application {

@Override
public void start(Stage primaryStage) {

Text text = new Text();

TextArea textArea = new TextArea();

Button btn = new Button();

Circle circle = new Circle();

VBox vb = new VBox();
vb.setPadding(new Insets(20,20,20,20));

text.setText("Testing JavaFX port with ant";

circle.setFill(Color.RED);
circle.setRadius(60);

btn.setText("PRINT";

btn.setOnAction(new EventHandler<ActionEvent>() {

@Override
public void handle(ActionEvent event) {
textArea.setText("testing JavaFX application on Android";
circle.setFill(Color.GREEN);
}
});
vb.getChildren().addAll(text,btn,textArea,circle);
ScrollPane root = new ScrollPane();
root.setContent(vb);


Scene scene = new Scene(root, 350, 550);

primaryStage.setTitle("JAVAFX PORT";
primaryStage.setScene(scene);
primaryStage.show();
}

/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}

}

Clean and build to create the jar file in the dist folder.


We will be using only JavaFX Main class for this tutorial. FXML and FXML Controller will be added in the next tutorial.

From the code and the Image, the application should explain itself.

Open the Visual Code Studio (Am using it as an Editor). Add this code to build an Android gradle project from the JavaFX project (FXANDROID).


set ANDROID_SDK=C:/Users/STEINACOZ-PC/AppData/Local/Android/sdk
set WORKDIR=C:/Users/STEINACOZ-PC/Documents/portingFX
set JFX_SDK=C:/dalvik-sdk-latest/dalvik-sdk
gradlew.bat --info --stacktrace createProject -PDEBUG -PDIR=%WORKDIR% -PPACKAGE=com.fxandroid -PNAME=FXANDROIDTUT -PANDROID_SDK=%ANDROID_SDK% -PJFX_SDK=%JFX_SDK% -PJFX_APP=C:/Users/STEINACOZ-PC/Documents/NetBeansProjects/FXAndroid/dist -PJFX_MAIN=fxandroid.FXAndroid

Name the file createFXANDROID.bat



it is actually a windows batch file.

-the first line sets the path to the android SDK installed in the system
-second line sets the output folder where the android gradle project will be created
-third line sets the path to the JavaFX dalvix SDK (where you unpacked it)
-the fourth line is the calls gradlew.bat shipped with JavaFX dalvix SDK, createProject command is called with the following parameters passed to it:
-PNAME = name of the android project and name to be created
-PPACKAGE = name of the android package to be created
-PJFX_APP = location of the JavaFX application jar file
-PJFX_MAIN = name of the JavaFX Main Class prefixed by the package name

Save the createFXANDROID.bat file in the same location JavaFX dalvix SDK, under android tools. Double click to run.


go to the output folder to see the new android gradle project

open command prompt, use cd command to enter into the new JavaFX android project.

use the command: ant debug

or

ant clean debug

This will create a debug-version (not signed) of the Android application in the bin subdirectory of the directory.

The Android application can now be transferred to a real Android device connected to your development system,
by calling $ANDROID_SDK/platform-tools/adb install -r bin/FXANDROIDTUT-debug.apk

if adb is part of the android sdk you downloaded.

if your usb port is broken like mine, transfer the apk to the android phone and install.

Be mindful of the footprint. JavaFX Desktop Applications have bigger footprints than their Android counterparts.

Wow, interesting. I have a question, What are the limitations? Why does the native development with Android SDK is better?

lekropasky:
Wow, interesting. I have a question, What are the limitations? Why does the native development with Android SDK is better?

Am back from my usual ban. Although am finding it difficult to understand your question but from the little I got.
One of the main limitations from my own point of view is the footprint i.e that is the changing from desktop size to mobile size. JavaFX yet doesn't support different screen responsiveness like html and co. It becomes a headache getting the right dimension for Android screens (mobile 720*1280 is not the same with desktop 720*1280).

Another one is that Android doesn't support Java 8 yet so you have to stay away from Java 8 specific API like lambda, stream etc but a plugin retrolambda takes care of lambda during the built.

Apart from that, other limitations should have work around like using Android specific API, you can import Android.jar from Android sdk into your project.