Getting the value from a custom input widget - dart

Question

I made a custom input widget by wrapping Textfield in some widgets and so on. Now I can't reach the onChanged property directly from the custom widget. I tried making a property in my custom widget but couldn't implement it properly. I googled passing variables between widgets and it seems a hard thing to do. Any simple solution?
class Input extends StatelessWidget {
final String text;
final TextInputType type;
final int maxLength;
final bool password;
final String label;
final IconData icon;
final double padding;
final Function onChanged;
final ColorSwatch color;
Input(
{this.type = TextInputType.text,
#required this.text,
this.maxLength,
this.icon,
this.padding = 0.0,
this.password = false,
#required this.onChanged,
this.label,
this.color});
final String value = '';
#override
Widget build(BuildContext context) {
return Padding(
padding: EdgeInsets.all(padding),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Padding(
padding: EdgeInsets.all(3.0),
child: Text(
text + ":",
style: TextStyle(fontSize: 15.0, color: color),
),
),
Container(
padding: EdgeInsets.all(3.0),
width: 300.0,
child: TextField(
obscureText: password,
decoration: InputDecoration(
labelText: label,
icon: Icon(icon),
),
maxLength: maxLength,
keyboardType: type,
textInputAction: TextInputAction.next,
onChanged: onChanged,
),
),
],
),
);
}
}

Answer 1

You need to provide onChanged and other events in your custom widget, even if you are just providing these to the underlying TextField. In other words, you need to pass the onChanged function down through your custom widget.
For example:
MyAwesomeTextField extends StatelessWidget {
/// Callback for being notified of changes to the text field
/// This should have a proper type, I'm just using Function for simplicity
final Function onChanged;
// Make the onChanged property settable through the constructor
MyAwesomeTextField({this.onChanged});
Widget build(BuildContext context) {
// Construct your widget tree, and pass your onChanged function through
return TextField(onChanged: this.onChanged);
}
}
Then when you're using it, your custom widget will have an onChanged event:
...
MyCustomWidget(onChanged: (value) => print(value) )
...