Simple Example Android API Code..

I’d like to write a simple example code of Android API but failed. Please give me some ideas.

The python code which is in “py_test.py” of “test1” python package folder :

from java import *

class py_print():
    def __init__(self, name):
        name="Chaquopy"
        print(name)

The Java code:

import com.chaquo.python.*;

public class MainActivity extends AppCompatActivity {
    protected Python py;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        py = Python.getInstance();
        PyObject py_test = py.getModule("test1.py_test");
        stream= py_test.py_print.call("Chaquopy");
        System.out.println(stream)

Plan to send a string to python from Java, and python return a string to Java. python can print the string from Java and Java can printh the string from python, to confirm if it works. Thanks.

[hushanhsiang]

It’s great to have your words. I modify my code to the three condition as below: Python code which is in “py_test.py” of “test1” python package folder:

from java import *


class py_class():
    def __init__(self, name):
        print( name)
    @property
    def py_return1(self):
        return("Return form py_return-1")

    @classmethod
    def py_return2(self):
        return("Return form py_return-2")

    def py_return3(self):
        return("Return form py_return-3")

Java side:

public class MainActivity extends AppCompatActivity {
    protected Python py;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        py = Python.getInstance();
        PyObject py_test = py.getModule("test1.py_test");

        PyObject stream =py_test.callAttr("py_class", "Oscar").get("py_return1");
        System.out.println(stream.toString());

        stream = py_test.get("py_class").callAttr("py_return2");
        System.out.println(stream.toString());

        stream = py_test.callAttr("py_class", "Chaquopy").callAttr("py_return3");
        System.out.println(stream.toString());

    }
}

There’s no any problem and the Logcat result:

01-30 08:03:34.014 4400-4400/com.oscarhu.python.java_call_py1 I/python.stdout: Oscar
01-30 08:03:34.014 4400-4400/com.oscarhu.python.java_call_py1 I/python.stdout:  
01-30 08:03:34.016 4400-4400/com.oscarhu.python.java_call_py1 I/System.out: Return form py_return-1
01-30 08:03:34.017 4400-4400/com.oscarhu.python.java_call_py1 I/System.out: Return form py_return-2
01-30 08:03:34.018 4400-4400/com.oscarhu.python.java_call_py1 I/python.stdout: Chaquopy
01-30 08:03:34.019 4400-4400/com.oscarhu.python.java_call_py1 I/python.stdout:  
01-30 08:03:34.020 4400-4400/com.oscarhu.python.java_call_py1 I/System.out: Return form py_return-3
01-30 08:03:34.037 4400-4642/com.oscarhu.python.java_call_py1 D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true

This simple example of Java API will be no problem with simple argument transmission. Thank you very much.

[hushanhsiang]

Ok, I knew above code will generate Grandle error, previously, I need your correction to let it work.

Is there a document to descript how Java can call the method of Python’s class or Python’s function? And I need a simple example.

Below modified code without Grandle error but Logcat generate: No module named 'test1.py_test.py_print'; 'test1.py_test' is not a package

package com.oscarhu.python.java_call_py1;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import com.chaquo.python.*;
public class MainActivity extends AppCompatActivity {
    protected Python py;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        py = Python.getInstance();
        PyObject py_test = py.getModule("test1.py_test.py_print");
        PyObject stream= py_test.call("Chaquopy");
        System.out.println(stream);

I need a way for Java call Python’s method and function with return a string. Thanks.