Added spaces to initial string for card number field

Author: wilburx9

lib/src/common/card_utils.dart

@@ -78,6 +78,7 @@ class CardUtils {
     return year;
   }
 
+  /// Removes non numerical characters from the string
   static String getCleanedNumber(String text) {
     if (text == null) {
       return '';

lib/src/common/utils.dart

@@ -51,4 +51,17 @@ class Utils {
       throw new InvalidEmailException(charge.email);
     }
   }
+
+  /// Add double spaces after every 4th character
+  static String addSpaces(String text) {
+    var buffer = new StringBuffer();
+    for (int i = 0; i < text.length; i++) {
+      buffer.write(text[i]);
+      var nonZeroIndex = i + 1;
+      if (nonZeroIndex % 4 == 0 && nonZeroIndex != text.length) {
+        buffer.write('  '); // Add double spaces.
+      }
+    }
+    return buffer.toString();
+  }
 }

lib/src/widgets/common/input_formatters.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+import 'package:flutter_paystack/src/common/utils.dart';
 
 class CardMonthInputFormatter extends TextInputFormatter {
   String previousText;
@@ -42,16 +43,7 @@ class CardNumberInputFormatter extends TextInputFormatter {
       return newValue;
     }
 
-    var buffer = new StringBuffer();
-    for (int i = 0; i < text.length; i++) {
-      buffer.write(text[i]);
-      var nonZeroIndex = i + 1;
-      if (nonZeroIndex % 4 == 0 && nonZeroIndex != text.length) {
-        buffer.write('  '); // Add double spaces.
-      }
-    }
-
-    var string = buffer.toString();
+    var string = Utils.addSpaces(text);
     return newValue.copyWith(
         text: string,
         selection: new TextSelection.collapsed(offset: string.length));

lib/src/widgets/input/card_input.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_paystack/src/common/card_utils.dart';
+import 'package:flutter_paystack/src/common/utils.dart';
 import 'package:flutter_paystack/src/models/card.dart';
 import 'package:flutter_paystack/src/widgets/buttons.dart';
 import 'package:flutter_paystack/src/widgets/input/cvc_field.dart';
@@ -36,8 +37,9 @@ class _CardInputState extends State<CardInput> {
     super.initState();
     numberController = new TextEditingController();
     numberController.addListener(_getCardTypeFrmNumber);
-    numberController.text =
-        _card != null && _card.number != null ? _card.number : null;
+    if (_card?.number != null) {
+      numberController.text = Utils.addSpaces(_card.number);
+    }
   }
 
   @override