problem accessing android jar in unity

[jainam]

hello developers!

I have an android project for camera flashlight, which when deployed from eclipse works fine. I am trying to access the flashlight function from my C# code in unity3d but it doesn’t work. To verify if I am calling the android method correctly, I created a string function in the same activity and it is returning the string correctly. I am not familiar to native android coding. It would be great if you could have a look at the code and help me out.

I know there are some threads in unity forums and stackoverflow, I tried to find a solution in almost all the links I could find but no luck!

Below is android MainActivity.java (which I converted into a jar file from eclipse and copied in unity project, ~Assets/Plugins/Android/bin/),

package com.example.newflash;

import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.Bundle;
import android.app.Activity;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {

	private static Camera camera;
    private static Parameters parameters;
	
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
        //Hide the window title.
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
	}
	
	public static String dummyString()
	{
		return "dummy string";
	}
	
	public static void setFlashOn()
	{
		if (camera == null)
			camera = Camera.open();
		parameters = camera.getParameters();
		parameters.setFlashMode(Parameters.FLASH_MODE_TORCH);
		camera.setParameters(parameters);
	}
	
	public static void setFlashOff()
	{
		parameters = camera.getParameters();
		parameters.setFlashMode(Parameters.FLASH_MODE_OFF);		
		camera.setParameters(parameters);
	}
}

Below is my unity C# code,

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System;

public class testJar : MonoBehaviour
{
	bool torchon;
	AndroidJavaClass testClasslight;
	
	void Start ()
	{
		torchon = false;
	}
	
	void OnGUI ()
	{
        string teststring = "empty";

		AndroidJavaClass testClass = new AndroidJavaClass("com.example.glassplaces.MainActivity");
		teststring = testClass.CallStatic<string>("dummyString");

        GUI.Label (new Rect (20, 20, 100, 60), teststring);
		
		if(GUI.Button(new Rect (20, 100, 100, 60), "ON"))
		{
			torchon = true;
		}
		
		if(torchon == true)
		{
			GUI.Label(new Rect(200, 20,100,60), "torch ON");
			testClass.CallStatic<AndroidJavaObject>("setFlashOn");
		}
    }
}

The permissions to access camera in AndroidManifest.xml when added, the app doesn’t start at all. On excluding the xml file from the project, the “dummyString” method still returns the string.

Below is the AndroidManifest.xml,

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.newflash"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />

    <uses-permission android:name="android.permission.CAMERA" />
    <uses-feature android:name="android.hardware.camera" />
    <uses-feature android:name="android.hardware.camera.autofocus" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/app_icon"
        android:label="@string/app_name">
        <activity
            android:name="com.example.newflash.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Below is the warning which unity shows in console with the above xml included during Build & Run,

Unable to find unity activity in manifest. You need to make sure orientation attribut is set to sensor manually.
UnityEditor.BuildPlayerWindow:BuildPlayerAndRun()

It would be great if someone could help me out. Any help is much appreciated.

Thank you in advance!

Jainam

[stevethorne]

Your activity in Java has to be an activity that extends “UnityPlayerActivity”, not your conventional “Activity”. That is, com.unity3d.player.UnityPlayerActivity. You can do a search here for UnityPlayerActivity to find out more about this.

[jainam]

I asked this question on the forum as my code didn’t work. So if you are using the above code, it won’t work Here is the working code…hope it helps

Create the package with the name “com.unity3d.player” in Android SDK.

Below is android MainActivity.java (which I converted into a jar file from eclipse and copied in unity project, ~Assets/Plugins/Android/bin/),

package com.unity3d.player;

import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.Bundle;
import android.view.WindowManager;
import android.content.Context;
import android.content.pm.PackageManager;

public class MainActivity extends UnityPlayerActivity {

	private static Camera camera;
    private static Parameters parameters;
    static boolean s;
    
	@Override
	protected void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        
        Context context = this;
		PackageManager packageManager = context.getPackageManager();
 
		// if device support camera?
		if (packageManager.hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)){
			//yes
			s = true;
		}else{
			//no
			s = false;
		}
    }
	
	public static String dummyString()
	{
		return "dummy string";
	}
	
	public static String sendFlashStatus()
	{
		if(s==true)
		{
			return "has flash";
		}
		else
		{
			return "no flash";
		}
	}
	
	public static String setFlashOn()
	{
		if (camera == null)
			camera = Camera.open();
		parameters = camera.getParameters();
		parameters.setFlashMode(Parameters.FLASH_MODE_TORCH);
		camera.setParameters(parameters);
		
		return "";
	}
	
	public static String setFlashOff()
	{
		parameters = camera.getParameters();
		parameters.setFlashMode(Parameters.FLASH_MODE_OFF);
		camera.setParameters(parameters);
		
		return "";
	}
}

Below is my unity C# code,

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System;

public class testJar : MonoBehaviour
{
	AndroidJavaClass testClass;
	string toggleMethod, somestring, hasFlash;
	bool callOnce;
	
	void Start ()
	{
		testClass = new AndroidJavaClass("com.unity3d.player.MainActivity");
		hasFlash = testClass.CallStatic<String>("sendFlashStatus");
		
		toggleMethod = "setFlashOff";
	}
	
	void Update ()
	{
		if(Input.GetKeyDown(KeyCode.Escape))
			Application.Quit();
	}
	
	void OnGUI ()
	{
		somestring = testClass.CallStatic<string>("dummyString");
        GUI.Label (new Rect (20, 20, 100, 60), somestring);
		
		
		GUI.Label (new Rect (150, 20, 100, 60), ""+hasFlash);
		
		if(GUI.Button(new Rect (Screen.width/2-50, Screen.height-120, 100, 60), "Toggle torch"))
		{
			callOnce = true;
			if(toggleMethod == "setFlashOff")
			{
				toggleMethod = "setFlashOn";
			}
			else
			{
				toggleMethod = "setFlashOff";
			}
		}

		if(callOnce)
		{
			testClass.CallStatic<AndroidJavaObject>(""+toggleMethod);
			callOnce = false;
		}
    }
}

Below is the AndroidManifest.xml,

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.unity3d.player"
	android:installLocation="preferExternal"
    android:versionCode="1"
    android:versionName="1.0">

	<supports-screens
        android:smallScreens="true"
        android:normalScreens="true"
        android:largeScreens="true"
        android:xlargeScreens="true"
        android:anyDensity="true"/>
	
	<uses-permission android:name="android.permission.CAMERA" />
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
	<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
	
	<application
		android:icon="@drawable/app_icon"
        android:label="@string/app_name"
        android:debuggable="true">
	<activity android:name="com.unity3d.player.MainActivity"
                  android:label="@string/app_name"
                  android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen">
		<intent-filter>
			<action android:name="android.intent.action.MAIN" />
			<category android:name="android.intent.category.LAUNCHER" />
		</intent-filter>
	</activity>
	
  </application>
</manifest>