add examples and more migrations

Author: ArturAssisComp

doc/migration.md

@@ -965,8 +965,33 @@ Validators.ip(
 );
 ```
 
-- `FormBuilderValidators.latitude()` - requires the field's to be a valid latitude.
-- `FormBuilderValidators.longitude()` - requires the field's to be a valid longitude.
+- `FormBuilderValidators.latitude()`: there is no equivalent to [this validator](https://github.com/flutter-form-builder-ecosystem/form_builder_validators/blob/17e982bb849dc68365f8fbc93d5a2323ee891c89/lib/src/network/latitude_validator.dart#L40). But something close would be: 
+```dart
+// Old API:
+FormBuilderValidators.latitude();
+
+// New API:
+Validators.transformAndValidate(
+  (String input) => input.replaceAll(',', '.'),
+  next: Validators.double(Validators.between(-90, 90)),
+);
+
+```
+
+- `FormBuilderValidators.longitude()`: there is no equivalent to [this validator](https://github.com/flutter-form-builder-ecosystem/form_builder_validators/blob/17e982bb849dc68365f8fbc93d5a2323ee891c89/lib/src/network/longitude_validator.dart#L40). But something close would be:
+```dart
+// Old API:
+FormBuilderValidators.longitude();
+
+// New API:
+Validators.transformAndValidate(
+  (String input) => input.replaceAll(',', '.'),
+  next: Validators.double(Validators.between(-180, 180)),
+);
+
+```
+
+TODO continue from here...
 - `FormBuilderValidators.macAddress()` - requires the field's to be a valid MAC address.
 - `FormBuilderValidators.phoneNumber()` - requires the field's value to be a valid phone number.
 - `FormBuilderValidators.portNumber()` - requires the field's to be a valid port number.

example/lib/generic_examples.dart

@@ -273,6 +273,28 @@ class GenericExamplesPage extends StatelessWidget {
                 textInputAction: TextInputAction.done,
                 autovalidateMode: AutovalidateMode.always,
               ),
+              TextFormField(
+                decoration: const InputDecoration(
+                  labelText: 'Latitude',
+                  prefixIcon: Icon(Icons.add_location),
+                ),
+                validator: V.required(V.transformAndValidate(
+                    (String input) => input.replaceAll(',', '.'),
+                    next: V.double(V.between(-90, 90)))),
+                textInputAction: TextInputAction.done,
+                autovalidateMode: AutovalidateMode.always,
+              ),
+              TextFormField(
+                decoration: const InputDecoration(
+                  labelText: 'Longitude',
+                  prefixIcon: Icon(Icons.add_location),
+                ),
+                validator: V.required(V.transformAndValidate(
+                    (String input) => input.replaceAll(',', '.'),
+                    next: V.double(V.between(-180, 180)))),
+                textInputAction: TextInputAction.done,
+                autovalidateMode: AutovalidateMode.always,
+              ),
             ],
           ),
         ),