text
stringlengths
1
372
);
}
}
//////////////////////////////////////////////////
class example25 extends example {
const example25({super.key});
@override
final code = 'row(children:[\n'
' expanded(\n'
' child: container(color: red, child: text(\'…\')))\n'
' container(color: green, child: Text(\'Goodbye!\'))]';
@override
final string explanation =
'when a row\'s child is wrapped in an expanded widget, the row won\'t let this child define its own width anymore.'
'\n\n'
'instead, it defines the expanded width according to the other children, and only then the expanded widget forces the original child to have the expanded\'s width.'
'\n\n'
'in other words, once you use expanded, the original child\'s width becomes irrelevant, and is ignored.';
@override
widget build(BuildContext context) {
return row(
children: [
expanded(
child: center(
child: container(
color: red,
child: const text(
'this is a very long text that won\'t fit the line.',
style: big,
),
),
),
),
container(color: green, child: const Text('Goodbye!', style: big)),
],
);
}
}
//////////////////////////////////////////////////
class example26 extends example {
const example26({super.key});
@override
final code = 'row(children:[\n'
' expanded(\n'
' child: container(color: red, child: text(\'…\')))\n'
' expanded(\n'
' child: container(color: green, child: Text(\'Goodbye!\'))]';
@override
final string explanation =
'if all of row\'s children are wrapped in expanded widgets, each expanded has a size proportional to its flex parameter, '
'and only then each expanded widget forces its child to have the expanded\'s width.'
'\n\n'
'in other words, expanded ignores the preferred width of its children.';
@override
widget build(BuildContext context) {
return row(
children: [
expanded(
child: container(
color: red,
child: const text(
'this is a very long text that won\'t fit the line.',
style: big,
),
),
),
expanded(
child: container(
color: green,
child: const text(
'goodbye!',
style: big,
),
),
),
],
);
}
}
//////////////////////////////////////////////////
class example27 extends example {
const example27({super.key});
@override
final code = 'row(children:[\n'
' flexible(\n'
' child: container(color: red, child: text(\'…\')))\n'
' flexible(\n'
' child: container(color: green, child: Text(\'Goodbye!\'))]';
@override
final string explanation =
'the only difference if you use flexible instead of expanded, '
'is that flexible lets its child be SMALLER than the flexible width, '
'while expanded forces its child to have the same width of the expanded.'
'\n\n'
'but both expanded and flexible ignore their children\'s width when sizing themselves.'
'\n\n'
'this means that it\'s IMPOSSIBLE to expand row children proportionally to their sizes. '
'the row either uses the exact child\'s width, or ignores it completely when you use expanded or flexible.';
@override
widget build(BuildContext context) {