button

UIButton

buttonWithType

UIButtonTypeCustom

];

button

addTarget

self

action:

@selector

showFlutter

forControlEvents:

UIControlEventTouchUpInside

];

button

setTitle

@"Show Flutter!"

forState

UIControlStateNormal

];

button

backgroundColor

UIColor

blueColor

button

frame

CGRectMake

80

210

160

40

);

self

view

addSubview