How to change the onPressed elevation in ElevatedButton Flutter - flutter

Question

Before version 2.0.1 of flutter I was using the RaisedButton and there was a property called focusElevation to change the elevation of the button for when it was pressed. So after deprecating it by Flutter and according to the documentations we should use the ElevatedButton instead. But now I can't find a way to change it with the style: property.
I know how to change the elevation but I want to change the onPressed elevation for when user presses it. As comes from its documentations there are some default values for it:
The button's elevations are defined relative to the elevation parameter. The disabled elevation is the same as the parameter value, elevation + 2 is used when the button is hovered or focused, and elevation + 6 is used when the button is pressed.
So any idea how to customize the onPressed elevation in ElevatedButton?

Answer 1

You can do it using the style property.
ElevatedButton(
style: ButtonStyle(
elevation: MaterialStateProperty.resolveWith<double>(
(Set<MaterialState> states) {
// if the button is pressed the elevation is 10.0, if not
// it is 5.0
if (states.contains(MaterialState.pressed))
return 10.0;
return 5.0;
},
),
),
)
Or you can combine it with the new ElevatedButton.styleFrom() property, by usign the merge method. Like this:
ElevatedButton.styleFrom(primary: Colors.red).merge(
ButtonStyle(
elevation: MaterialStateProperty.resolveWith<double>(
(Set<MaterialState> states) {
if (states.contains(MaterialState.pressed))
return 10.0;
return 5.0;
},
),
),
),
),

Answer 2

final ButtonStyle raisedButtonStyle = ElevatedButton.styleFrom(
onPrimary: Colors.transparent,
primary: Colors.transparent, // transparent
padding: EdgeInsets.symmetric(horizontal: 16),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.all(Radius.circular(25)),
),
).merge(
ButtonStyle(elevation: MaterialStateProperty.resolveWith<double>((Set<MaterialState> states) {
if (states.contains(MaterialState.pressed)) return 16; // 点击时阴影隐藏
return 0; // 正常时阴影隐藏
})),
);
ElevatedButton(
style: raisedButtonStyle,
onPressed: () {
},
child: Text("click"),
)