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Text : Picker_unity.txt

using UnityEngine;

public class PickAudio : MonoBehaviour {

private string selectedFilePath;

public void PickFile () {
        AndroidJavaClass intentClass = new AndroidJavaClass("android.content.Intent");
        AndroidJavaObject intentObject = new AndroidJavaObject("android.content.Intent");

intentObject.Call<AndroidJavaObject>("setType", "audio/*");
        intentObject.Call<AndroidJavaObject>("setAction", intentClass.GetStatic<string>("ACTION_GET_CONTENT"));

AndroidJavaClass unity = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
        AndroidJavaObject currentActivity = unity.GetStatic<AndroidJavaObject>("currentActivity");

currentActivity.Call("startActivityForResult", intentObject, 0);
    }

public void OnActivityResult (string data) {
        selectedFilePath = data;
    }

public string GetSelectedFilePath () {
        return selectedFilePath;
    }

}

// Permission

using UnityEngine;

public class RequestPermissions : MonoBehaviour {

private const int REQUEST_CODE = 123;

public void RequestStoragePermission () {
        AndroidJavaObject activity = new AndroidJavaClass("com.unity3d.player.UnityPlayer").GetStatic<AndroidJavaObject>("currentActivity");

string[] permissions = { "android.permission.READ_EXTERNAL_STORAGE", "android.permission.WRITE_EXTERNAL_STORAGE" };
        AndroidJavaObject permissionObj = new AndroidJavaObject("android.Manifest$permission");
        AndroidJavaObject permissionArray = new AndroidJavaObject("java.util.ArrayList");

for (int i = 0; i < permissions.Length; i++) {
            permissionArray.Call<bool>("add", permissionObj.GetStatic<string>(permissions[i]));
        }

AndroidJavaClass permissionClass = new AndroidJavaClass("com.unity3d.player.PermissionHelper");
        permissionClass.CallStatic("requestPermissions", activity, permissionArray, REQUEST_CODE);
    }

public void OnRequestPermissionsResult (string result) {
        // Handle permission result
    }

}

//// Check permission

using UnityEngine;

public class CheckPermissions : MonoBehaviour {

public bool IsStoragePermissionGranted () {
        AndroidJavaObject activity = new AndroidJavaClass("com.unity3d.player.UnityPlayer").GetStatic<AndroidJavaObject>("currentActivity");
        AndroidJavaObject context = activity.Call<AndroidJavaObject>("getApplicationContext");

string permission = "android.permission.READ_EXTERNAL_STORAGE";
        int result = context.Call<int>("checkSelfPermission", permission);

return result == AndroidJavaObject.GetStatic<int>("PackageManager.PERMISSION_GRANTED");
    }

}