tying to launch SMS app from fragment

i use this code in my activity class :

 public void Sms(String s){
        Intent intent=new Intent(Intent.ACTION_VIEW, Uri.fromParts("sms", s, null));
        PackageManager packageManager = getPackageManager();
        List activities = packageManager.queryIntentActivities(intent,
                PackageManager.MATCH_DEFAULT_ONLY);
        boolean isIntentSafe = activities.size() > 0;
        if(isIntentSafe)
        {  startActivity(intent);
        }else{
            Toast.makeText(MainActivity.context,getString(R.string.actionNonSupportee),Toast.LENGTH_LONG).show();
        }
    }

it works very well

but when i use the same code in my fragment class

 public void Sms(String s){
        Intent intent=new Intent(Intent.ACTION_VIEW, Uri.fromParts("sms", s, null));
        PackageManager packageManager = getActivity().getPackageManager();
        List activities = packageManager.queryIntentActivities(intent,
                PackageManager.MATCH_DEFAULT_ONLY);
        boolean isIntentSafe = activities.size() > 0;
        if(isIntentSafe)
        {  startActivity(intent);
        }else{
            Toast.makeText(MainActivity.context,getString(R.string.actionNonSupportee),Toast.LENGTH_LONG).show();
        }
    }

the app crashes.

The only line I changed is :

    PackageManager packageManager = getActivity().getPackageManager();