Facebook Unity SDK on Android crashes when fb.init is called

Question

I'm working facebook unity SDK, everything is fine on unity editor, but doesn't work on android device. "App stopped" when fb.init called.

I use unity 5.5.1 version and facebook sdk version is 7.9.4

here is code :

public void teststr()
    {
        if (!FB.IsInitialized) {
            // Initialize the Facebook SDK
            FB.Init(InitCallback, OnHideUnity);
        } else {

            // Already initialized, signal an app activation App Event

        }
    }
    private void InitCallback ()
    {
        if (FB.IsInitialized) {
            // ...

        } else {

        }
    }
private void OnHideUnity (bool isGameShown)
    {
        if (!isGameShown) {

            // Pause the game - we will need to hide
            Time.timeScale = 0;
        } else {

            // Resume the game - we're getting focus again
            Time.timeScale = 1;
        }
    }

teststr function fires when I clicked button

Answer 1

I've solved!

I use FB.Init(this.InitCallback, this.OnHideUnity);

instead of FB.Init(InitCallback, OnHideUnity);