Initial commit.

.gitignore

+.idea

main.py

+from enum import Enum
+
+from kivy.app import App
+from kivy.properties import StringProperty
+
+
+class Classification(Enum):
+    INVALID = 'Invalid'
+    EQUILATERAL = 'Equilateral'
+    ISOSCELES = 'Isosceles'
+    RIGHT = 'Right'
+    SCALENE = 'Scalene'
+
+
+class TriangleApp(App):
+    classification = StringProperty()
+
+    def update(self):
+        ids = self.root.ids
+        try:
+            a = int(ids.a.text)
+            b = int(ids.b.text)
+            c = int(ids.c.text)
+            if a + b + c != 180:
+                self.classification = Classification.INVALID.value
+            else:
+                angles = frozenset((a, b, c))
+                if any(not 0 < angle < 180 for angle in angles):
+                    self.classification = Classification.INVALID.value
+                elif 90 in angles:
+                    self.classification = Classification.RIGHT.value
+                else:
+                    self.classification = {
+                        1: Classification.EQUILATERAL.value,
+                        2: Classification.ISOSCELES.value,
+                        3: Classification.SCALENE.value,
+                    }[len(angles)]
+        except ValueError:
+            self.classification = f'{Classification.INVALID.value} (non-integer angles)'
+
+    def on_start(self):
+        self.update()
+
+
+if __name__ == '__main__':
+    app = TriangleApp()
+    app.run()

triangle.kv

+BoxLayout:
+    orientation: 'vertical'
+    Widget:
+    BoxLayout:
+        orientation: 'horizontal'
+        size_hint: (1, 0)
+        height: 40
+        Widget:
+            size_hint: (0.25, 0)
+        Label:
+            text: 'Angle A (degrees):'
+            font_size: 36
+        TextInput:
+            id: a
+            multiline: False
+            write_tab: False
+            text: ''
+            font_size: 24
+            on_text: app.update()
+        Widget:
+            size_hint: (0.25, 0)
+    BoxLayout:
+        orientation: 'horizontal'
+        size_hint: (1, 0)
+        height: 40
+        Widget:
+            size_hint: (0.25, 0)
+        Label:
+            text: 'Angle B (degrees):'
+            font_size: 36
+        TextInput:
+            id: b
+            multiline: False
+            write_tab: False
+            text: ''
+            font_size: 24
+            on_text: app.update()
+        Widget:
+            size_hint: (0.25, 0)
+    BoxLayout:
+        orientation: 'horizontal'
+        size_hint: (1, 0)
+        height: 40
+        Widget:
+            size_hint: (0.25, 0)
+        Label:
+            text: 'Angle C (degrees):'
+            font_size: 36
+        TextInput:
+            id: c
+            multiline: False
+            write_tab: False
+            text: ''
+            font_size: 24
+            on_text: app.update()
+        Widget:
+            size_hint: (0.25, 0)
+    Widget:
+        size_hint: (1, 0)
+        height: 40
+    BoxLayout:
+        orientation: 'horizontal'
+        size_hint: (1, 0)
+        height: 40
+        Widget:
+        Label:
+            text: app.classification
+            font_size: 36
+        Widget:
+    Widget: