Сделал экраны Проведения покупки

lib/main.dart

@@ -31,6 +31,7 @@ const Color textBorderColor = const Color(0xffcfd8dc);
 const Color textFieldBackground = const Color(0xffefefef);
 const Color tokenActiveTextColor = const Color(0xff1f5a1f);
 const Color tokenActivateTextColor = const Color(0xff4e3a19);
+const Color greenBackground = const Color(0xff8ae28a);
 
 // Margins
 const double verticalMargin = 28.0;
@@ -71,6 +72,7 @@ startScanner(BuildContext context) async {
 
   });
   
+  Navigator.of(context).pop();
   await platform.invokeMethod('startScanner');
 }
 

lib/purchase.dart

@@ -32,7 +32,7 @@ class PurchaseScreenState<T> extends BaseState<T> {
   }
 
   @override Widget getScreenContent() {
-    return new Container(height: 398.0,
+    return new Container(height: 412.0,
         child: new ListView(reverse: true, children: <Widget>[
           new Column(children: <Widget>[
             getValueWithTitle('ФИО', 'Знаменитый Рокер Паук'),
@@ -40,38 +40,33 @@ class PurchaseScreenState<T> extends BaseState<T> {
             getValueWithTitle('Вознаграждение', '100%'),
             getHintLabel(),
             getDecoratedTextWidget(),
-            getApprovePurchaseButton(context),
+            buildButton(new EdgeInsets.only(top: 36.0, left: 70.0, right: 70.0), buildRaisedButton(context, 'ЗАВЕРШИТЬ ПОКУПКУ', () => _purchase(context))),
-            buildScanButton(context)])
+            buildButton(new EdgeInsets.only(top: 24.0, left: 70.0, right: 70.0), buildFlatButton(context, 'СКАНИРОВАТЬ', primaryColor))])
         ].reversed.toList()));
   }
 
   Widget getValueWithTitle(String title, String value) {
-  	return new Container(padding: new EdgeInsets.only(left: verticalMargin, right: verticalMargin, top: 12.0),
+  	return new Container(padding: new EdgeInsets.only(left: verticalMargin, right: verticalMargin, top: 18.0),
      child: new Column(children: <Widget>[
   		new Row(crossAxisAlignment: CrossAxisAlignment.start, children: <Widget>[new Text(title, textAlign: TextAlign.left, style: new TextStyle(color: greyTextColor, fontSize: 14.0))]),
   		new Row(crossAxisAlignment: CrossAxisAlignment.start, children: <Widget>[new Text(value, textAlign: TextAlign.left, style: new TextStyle(color: Colors.black, fontSize: 20.0))])
   	]));
   }
 
-  Widget getApprovePurchaseButton(BuildContext context) {
+  Widget buildButton(EdgeInsets margin, Widget widget) {
-    return new Container(margin: new EdgeInsets.only(top: 36.0), height: 44.0,
+    return new Container(margin: margin, height: 48.0, child: new Row(children: <Widget>[new Expanded(child: widget)]));
-            child: new RaisedButton(child: new Text('ЗАВЕРШИТЬ ПОКУПКУ',
+  }
+ 
+  Widget buildRaisedButton(BuildContext context, String text, VoidCallback onPressed) {
+    return new RaisedButton(child: new Text(text,
                 style: new TextStyle(color: Colors.white)),
-                onPressed: () => _purchase(context),
+                onPressed: onPressed,
-                color: primaryColor));
+                color: primaryColor);
   }
 
-  Widget buildScanButton(BuildContext context) {
+  Widget buildFlatButton(BuildContext context, String title, Color textColor) {
-    return new Container(margin: new EdgeInsets.only(top: 24.0, left: 70.0, right: 70.0), child: _getScanButtonRow(context));
+    return new Container(height: 48.0, child: new FlatButton(child: new Text(title,
-  }
+        style: new TextStyle(color: textColor)),
-
-  Widget _getScanButtonRow(BuildContext context) {
-    return new Row(children: <Widget>[new Expanded(child: _getScanButton(context))]);
-  }
-
-  Widget _getScanButton(BuildContext context) {
-    return new Container(height: 44.0, child: new FlatButton(child: new Text('СКАНИРОВАТЬ',
-        style: new TextStyle(color: primaryColor)),
         onPressed: () => startScanner(context)),
         decoration: _getDecoraionForScanButton());
   }

lib/purchase_success.dart

@@ -27,12 +27,16 @@ class _PurchaseSuccessScreenState<T> extends PurchaseScreenState<T> {
     return new Column(children: <Widget>[
             getValueWithTitle('Покупатель', 'Знаменитый Рокер Паук'),
             _getSuccessMessage(),
-            getApprovePurchaseButton(context)
+            new Expanded(child: new Center()),
+            buildButton(new EdgeInsets.only(bottom: 74.0, left: 70.0, right: 70.0), buildRaisedButton(context, 'СКАНИРОВАТЬ', () => startScanner(context)))
         ]);
   }
 
   _getSuccessMessage() {
-  	return new Container(height: 64.0, decoration: new BoxDecoration(color: const Color(0x8ae28aff)), child: new Text('Покупка на сумму 1234.00 руб. проведена', style: new TextStyle(color: tokenActiveTextColor)));
+  	return new Row(children: <Widget>[new Expanded(child: new Container(margin: new EdgeInsets.only(top: 20.0), height: 64.0,
+      decoration: new BoxDecoration(color: greenBackground),
+      child: new Center(child: new Text('Покупка на сумму 1234.00 руб. проведена', textAlign: TextAlign.center,
+        style: new TextStyle(fontWeight: FontWeight.bold, color: tokenActiveTextColor)))))]);
   }
 
 }