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final code = 'constrainedbox(\n'
' constraints: BoxConstraints(\n'
' minWidth: 70, minHeight: 70,\n'
' maxWidth: 150, maxHeight: 150),\n'
' child: container(color: red, width: 10, height: 10)))';
@override
final string explanation =
'you might guess that the container has to be between 70 and 150 pixels, but you would be wrong. '
'the ConstrainedBox only imposes ADDITIONAL constraints from those it receives from its parent.'
'\n\n'
'here, the screen forces the ConstrainedBox to be exactly the same size as the screen, '
'so it tells its child container to also assume the size of the screen, '
'thus ignoring its \'constraints\' parameter.';
@override
widget build(BuildContext context) {
return ConstrainedBox(
constraints: const BoxConstraints(
minWidth: 70,
minHeight: 70,
maxWidth: 150,
maxHeight: 150,
),
child: container(color: red, width: 10, height: 10),
);
}
}
//////////////////////////////////////////////////
class example10 extends example {
const example10({super.key});
@override
final code = 'center(\n'
' child: ConstrainedBox(\n'
' constraints: BoxConstraints(\n'
' minWidth: 70, minHeight: 70,\n'
' maxWidth: 150, maxHeight: 150),\n'
' child: container(color: red, width: 10, height: 10))))';
@override
final string explanation =
'now, center allows ConstrainedBox to be any size up to the screen size.'
'\n\n'
'the ConstrainedBox imposes ADDITIONAL constraints from its \'constraints\' parameter onto its child.'
'\n\n'
'the container must be between 70 and 150 pixels. it wants to have 10 pixels, so it will end up having 70 (the MINIMUM).';
@override
widget build(BuildContext context) {
return center(
child: ConstrainedBox(
constraints: const BoxConstraints(
minWidth: 70,
minHeight: 70,
maxWidth: 150,
maxHeight: 150,
),
child: container(color: red, width: 10, height: 10),
),
);
}
}
//////////////////////////////////////////////////
class example11 extends example {
const example11({super.key});
@override
final code = 'center(\n'
' child: ConstrainedBox(\n'
' constraints: BoxConstraints(\n'
' minWidth: 70, minHeight: 70,\n'
' maxWidth: 150, maxHeight: 150),\n'
' child: container(color: red, width: 1000, height: 1000))))';
@override
final string explanation =
'center allows ConstrainedBox to be any size up to the screen size.'
'the ConstrainedBox imposes ADDITIONAL constraints from its \'constraints\' parameter onto its child'
'\n\n'
'the container must be between 70 and 150 pixels. it wants to have 1000 pixels, so it ends up having 150 (the MAXIMUM).';
@override
widget build(BuildContext context) {
return center(
child: ConstrainedBox(
constraints: const BoxConstraints(
minWidth: 70,
minHeight: 70,
maxWidth: 150,
maxHeight: 150,
),
child: container(color: red, width: 1000, height: 1000),
),
);
}
}
//////////////////////////////////////////////////
class example12 extends example {
const example12({super.key});
@override
final code = 'center(\n'
' child: ConstrainedBox(\n'
' constraints: BoxConstraints(\n'
' minWidth: 70, minHeight: 70,\n'
' maxWidth: 150, maxHeight: 150),\n'
' child: container(color: red, width: 100, height: 100))))';
@override