RaisedButton is not deifined

[hadimajidi]

Failure Logs

[{
"resource": "/c:/src/argon-flutter-master/lib/screens/elements.dart",
"owner": "generated_diagnostic_collection_name#1",
"code": {
"value": "undefined_method",
"target": {
"$mid": 1,
"external": "https://dart.dev/diagnostics/undefined_method",
"path": "/diagnostics/undefined_method",
"scheme": "https",
"authority": "dart.dev"
}
},
"severity": 8,
"message": "The method 'RaisedButton' isn't defined for the type '_ElementsState'.\nTry correcting the name to the name of an existing method, or defining a method named 'RaisedButton'.",
"source": "dart",
"startLineNumber": 58,
"startColumn": 26,
"endLineNumber": 58,
"endColumn": 38
}]

[{
"resource": "/c:/src/argon-flutter-master/lib/screens/onboarding.dart",
"owner": "generated_diagnostic_collection_name#1",
"code": {
"value": "undefined_method",
"target": {
"$mid": 1,
"external": "https://dart.dev/diagnostics/undefined_method",
"path": "/diagnostics/undefined_method",
"scheme": "https",
"authority": "dart.dev"
}
},
"severity": 8,
"message": "The method 'FlatButton' isn't defined for the type 'Onboarding'.\nTry correcting the name to the name of an existing method, or defining a method named 'FlatButton'.",
"source": "dart",
"startLineNumber": 54,
"startColumn": 28,
"endLineNumber": 54,
"endColumn": 38
}]

[robert-stevens]

RaisedButton is now deprecated and replaced by ElevatedButton.