I define a customads and in native code ios, I have write bellow code: Code: -(void)showCustomFullscreenAd{ //PTPScreen *screen = PTPScreen::getTopScreen(); PTPScreen *screen = PTPScreen::getRunningScreen(); std::vector<PTPObjectButton*> btns = screen->getButtons("Cross1"); PTPObjectButton *btn = screen->getButton("Cross1"); if (btn != NULL) { NSLog(@"PTPObjectButton"); } } But variable *btns* size alway equals zero and *btn* alway is NULL.And in class PTPScreen, I see some methods: PTPObjectButton* getButton( const char* key ); std::vector<PTPObjectButton*> getButtons(conststd::string &key); What is *key*? If can get PTPObjectButton then can i change button image? Please help me! Thank for advance!