auto buttt = ui::Button::create();
buttt->setPosition(Vec2(windowSize.width/2, windowSize.height/2));
buttt->setColor(Color3B::GREEN);
buttt->setTitleText(“heeee”);
this->addChild(buttt);
but button is not display anywhere 
auto buttt = ui::Button::create();
buttt->setPosition(Vec2(windowSize.width/2, windowSize.height/2));
buttt->setColor(Color3B::GREEN);
buttt->setTitleText(“heeee”);
this->addChild(buttt);
but button is not display anywhere 
try giving it a size?
yes i have give it content size
I don’t see that in the code you provided.