rework purchase sum parsing (was broken on Flutter revision f2af347363, Dart version 1.25.0-dev.7.0, refs #9991

lib/purchase.dart

@@ -24,8 +24,6 @@ class PurchaseScreen extends StatefulWidget {
 
 class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
 
-  RegExp moneyRegexp = new RegExp(r'''^(?!0\.00)\d{1,11}(\.\d{0,2})?$''');
-
   PurchaseScreenState(String userString, String card) {
     this.user = JSON.decode(userString);
     this.card = card;
@@ -34,7 +32,6 @@ class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
 
   Map user;
   String card = '';
-  String integerPart = '', fractionalPart = '';
   String loyality = '';
 
   @override Widget getScreenContent() {
@@ -66,39 +63,22 @@ class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
     return Colors.white;
   }
 
-  /// Смена состояния экрана при изменении текста в поле ввода.
-  @override handleUserInput(String tmpString) {
-
-    setState(() {
-
-      if (tmpString.length == 0 || moneyRegexp.hasMatch(tmpString)) {
-        if (tmpString.contains('.')) {
-          int dotIndex = tmpString.indexOf('.');
-          integerPart = tmpString.substring(0, dotIndex);
-          fractionalPart = tmpString.substring(dotIndex + 1, tmpString.length);
-          if (fractionalPart.length > 2) {
-            fractionalPart = fractionalPart.substring(0, 2);
-          }
-          controller.text = '${integerPart}.${fractionalPart}';
-        } else {
-          integerPart = tmpString;
-          controller.text = tmpString;
-        }
-        textFieldValue = tmpString;
-
-      } else {
-        tmpString = tmpString.substring(0, tmpString.length - 1);
-        controller.text = tmpString.replaceAll('a', '');
-        textFieldValue = tmpString;
-      }
-    });
-  }
-
   @override getTextWidget() {
-    return new TextField(keyboardType: TextInputType.number, decoration: new InputDecoration.collapsed(hintText: getHint(),
-      hintStyle: new TextStyle(color: greyTextColor, fontSize: 16.0)),
+    return new TextField(
+        keyboardType: TextInputType.number,
+        decoration: new InputDecoration.collapsed(
+          hintText: getHint(),
+          hintStyle: new TextStyle(color: greyTextColor, fontSize: 16.0)
+        ),
         controller: controller,
-      onChanged: (text) => handleUserInput(text));
+        onSubmitted: (String text) {
+          setState(() {
+            controller.text = _parseSum(text);
+          });
+        },
+        textAlign: TextAlign.center,
+        autofocus: true,
+    );
   }
 
   getLoyality(String url) async {
@@ -131,24 +111,44 @@ class PurchaseScreenState<T> extends BaseState<PurchaseScreen> {
     }
   }
 
-  _buildSum() {
-    String temporaryInteger = integerPart;
-    String temporaryFractional = fractionalPart;
+  String _cleanupNumber(String text){
+    String tmp = text
+      .replaceAll(' ', '')
+      .replaceAll('-', '')
+      .replaceAll(',', '.')
+      .replaceAll('..', '.');
 
-    while (temporaryFractional.length < 2) {
-      temporaryFractional = temporaryFractional + '0';
+    while(tmp.indexOf('..') != -1){
+      tmp = tmp.replaceAll('..', '.');
+    }
+    return tmp;
   }
 
-    if (temporaryInteger.length == 0) {
-      temporaryInteger = '0';
-    }
+  _parseSum(String input) {
+    num sumTotal = 0.0;
+    String text = _cleanupNumber(input);
 
-    return temporaryInteger + '.' + temporaryFractional;
+    try {
+      sumTotal = num.parse(text);
+    } catch(exception, stacktrace) {
+      print(exception);
+      try {
+        int idx = text.indexOf('.');
+        String integerPart = text.substring(0, idx);
+        String fractionalPart = text.substring(idx + 1, text.length);
+        if(fractionalPart.length > 2) {
+          fractionalPart = fractionalPart.substring(0, 2);
+        }
+        return '${integerPart}.${fractionalPart}';
+      } catch(exception, stacktrace){
+        print(exception);
+      }
+    }
+    return sumTotal.toStringAsFixed(2);
   }
 
   onPurchaseClick(BuildContext context) {
-    String val = _buildSum();
-    print(val);
+    String val = _parseSum(controller.text);
     showDialog(context: context, child: new AlertDialog(
       title: new Text('Подтверждение'),
       content: new Text('Вы подтверждаете покупку на ${val} руб?'),