First are obsolete classes. Quotes from the Flutter documentation: FlatButton, RaisedButton, and OutlineButton have been replaced by TextButton, ElevatedButton, and OutlinedButton respectively.
Read moreHow do you increase outlined button size in flutter?
We can control the size of an outlined button by using the fixedSize option of the styleFrom static method .
Read moreHow do you change the height and width of an ElevatedButton in flutter?
“how to define height width for elevatedbutton in flutter” Code Answer’s
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