Calling Android NDK function from Unity Script

Question

So I\'m creating an Android app that uses Unity ... I am getting some assetbundle from Unity but I do not know the url before Unity starts. Thus Unity needs to call a funct

Answer 1

You could likely send the 'dynamic' url in your call to getURL. Do something like:

return plugin.Call<string>("getURL", new object[] {"http://thisIsMyUrl.com"});

and then your java looking like this:

public String getURL(Object newUrl) {
    return newUrl.ToString();
}

Answer 2

I suggest ditch the NDK. Use the Android java plugin.

In YourPlugin.cs:

using UnityEngine;
using System.Collections;
using System.IO;

#if UNITY_ANDROID
public class UnityUrlPlugin {

  // Logs the user out and invalidates the token
  public static string getUrl() {
    if( Application.platform != RuntimePlatform.Android )
      return;

    var pluginClass = new AndroidJavaClass("com.you.UnityUrlPlugin") ;
    AndroidJavaObject plugin = pluginClass.CallStatic<AndroidJavaObject>("instance");
    return plugin.Call<string>("getURL");
  } 
}
#endif

Then, in UnityUrlPlugin.java:

package com.you;

import android.content.ContentValues;
import android.content.Intent;
import android.os.Environment;

public class UnityUrlPlugin {

  private static UnityUrlPlugin m_instance;

  public static UnityUrlPlugin instance() {
    if(m_instance == null)
      m_instance = new UnityUrlPlugin();
    return m_instance;
  }

  private UnityUrlPlugin(){
  }

  public String getURL() {
    return "http://blah.com";
  }
}

And throw UnityUrlPlugin.jar in to Assets/Plugins/Android folder.

No need for NDK!