kivy: use RecycleView in OutputList

gui/kivy/main.kv

@@ -114,17 +114,26 @@
 
 
 <OutputList>
-    height: self.minimum_height
-    size_hint_y: None
-    cols: 1
-    spacing: '10dp'
-    padding: '10dp'
-    canvas.before:
-        Color:
-            rgb: .3, .3, .3
-        Rectangle:
-            size: self.size
-            pos: self.pos
+    viewclass: 'OutputItem'
+    size_hint: 1, None
+    height: min(output_list_layout.minimum_height, dp(144))
+    scroll_type: ['bars', 'content']
+    bar_width: dp(15)
+    RecycleBoxLayout:
+        orientation: 'vertical'
+        default_size: None, pt(6)
+        default_size_hint: 1, None
+        size_hint: 1, None
+        height: self.minimum_height
+        id: output_list_layout
+        spacing: '10dp'
+        padding: '10dp'
+        canvas.before:
+            Color:
+                rgb: .3, .3, .3
+            Rectangle:
+                size: self.size
+                pos: self.pos
 
 <RefLabel>
     font_size: '6pt'

gui/kivy/uix/dialogs/__init__.py

@@ -3,6 +3,8 @@ from kivy.clock import Clock
 from kivy.factory import Factory
 from kivy.properties import NumericProperty, StringProperty, BooleanProperty
 from kivy.core.window import Window
+from kivy.uix.recycleview import RecycleView
+from kivy.uix.boxlayout import BoxLayout
 
 from electrum_gui.kivy.i18n import _
 
@@ -193,25 +195,21 @@ class InfoBubble(Factory.Bubble):
 
 
 
-class OutputItem(Factory.BoxLayout):
+class OutputItem(BoxLayout):
     pass
 
-class OutputList(Factory.GridLayout):
+class OutputList(RecycleView):
 
     def __init__(self, **kwargs):
-        super(Factory.GridLayout, self).__init__(**kwargs)
+        super(OutputList, self).__init__(**kwargs)
         self.app = App.get_running_app()
 
     def update(self, outputs):
-        self.clear_widgets()
+        res = []
         for (type, address, amount) in outputs:
-            self.add_output(address, amount)
-
-    def add_output(self, address, amount):
-        b = Factory.OutputItem()
-        b.address = address
-        b.value = self.app.format_amount_and_units(amount)
-        self.add_widget(b)
+            value = self.app.format_amount_and_units(amount)
+            res.append({'address': address, 'value': value})
+        self.data = res
 
 
 class TopLabel(Factory.Label):

gui/kivy/uix/dialogs/tx_dialog.py

@@ -57,17 +57,15 @@ Builder.load_string('''
                     BoxLabel:
                         text: _('Transaction fee') if root.fee_str else ''
                         value: root.fee_str
-                TopLabel:
-                    text: _('Outputs') + ':'
-                OutputList:
-                    height: self.minimum_height
-                    size_hint: 1, None
-                    id: output_list
                 TopLabel:
                     text: _('Transaction ID') + ':' if root.tx_hash else ''
                 TxHashLabel:
                     data: root.tx_hash
                     name: _('Transaction ID')
+                TopLabel:
+                    text: _('Outputs') + ':'
+                OutputList:
+                    id: output_list
         Widget:
             size_hint: 1, 0.1