Hook Crash with makeText method of Toast

[TheKop]

Hi
I'm trying to hook method makeText of class android/widget/Toast
But it crash.
Please let me know code is wrong or current your library still not support?

////////Code Start

void do_patch()
{
dalvik_hook_setup(&sb1, "Landroid/widget/Toast;", "makeText", "(Landroid/content/Context;Ljava/lang/CharSequence;I)Landroid/widget/Toast;", 4, makeText);
dalvik_hook(&d, &sb1);

}

// patches
static void* makeText(JNIEnv *env, jobject context ,jobject txt, jint time)
{
log("Prepare Hook Toast\n")
dalvik_prepare(&d, &sb1, env);
jclass Toast = NULL;
jobject toast = NULL;
jmethodID makeText = NULL;

log("FindClass Toast\n")
Toast = (*env)->FindClass(env, "android/widget/Toast");
if(NULL == Toast)
{
    log("FindClass failed")
    return;
}
log("Method name = %s\n",sb1.method_name)

log("Get parameters\n")

jmethodID mid = (*env)->GetMethodID(env, (*env)->GetObjectClass(env, txt), "toString", "()Ljava/lang/String;");
jstring string = (jstring)((*env)->CallObjectMethod(env, txt, mid));
const char* utf = (*env)->GetStringUTFChars(env, string, 0);
if (utf) {
    log("txt : %s , time = %d\n", utf,time)
    (*env)->ReleaseStringUTFChars(env, string, utf);
}

log("Prepare CallStaticObjectMethod\n")
toast = (*env)->CallStaticObjectMethod(env, Toast, sb1.mid, context,txt,time);  //Crash at this line of code
if ( NULL == toast) 
{
    log("CALLSTATICOBJECT FAILED")
    return;
}

log("dalvik_postcall\n")
dalvik_postcall(&d, &sb1);

//Just test
return NULL;

}

/////Code End
Thanks you very much