Split out controllers/views, add additional UI utilities

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>

bin/subiquity

@@ -19,7 +19,7 @@ import sys
 import urwid
 import urwid.curses_display
 from subiquity.palette import STYLES
-from subiquity.views import StartView
+from subiquity.controllers.welcome import WelcomeController
 
 
 def parse_options(argv):
@@ -45,7 +45,7 @@ def main():
     def unhandled_input(key):
         if key in ('Q', 'q', 'esc'):
             raise urwid.ExitMainLoop()
-    urwid.MainLoop(StartView(), screen=screen,
+    urwid.MainLoop(WelcomeController().show(), screen=screen,
                    unhandled_input=unhandled_input).run()
 
 if __name__ == '__main__':

subiquity/controllers/__init__.py

@@ -0,0 +1,43 @@
+# Copyright 2015 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from abc import ABCMeta, abstractmethod
+
+
+class BaseController(metaclass=ABCMeta):
+    controller_name = None
+
+    @classmethod
+    def name(cls):
+        if cls.controller_name:
+            return cls.controller_name
+        return cls.__name__.lower()
+
+    @abstractmethod
+    def show(self):
+        """ Implements show action for the controller
+
+        Renders the View for controller.
+        """
+        pass
+
+    @abstractmethod
+    def finish(self):
+        """ Implements finish action for controller.
+
+        This handles any callback data/procedures required
+        to move to the next controller or end the install.
+        """
+        pass

subiquity/controllers/welcome.py

@@ -0,0 +1,28 @@
+# Copyright 2015 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from subiquity.controllers import BaseController
+from subiquity.views.welcome import WelcomeView
+
+
+class WelcomeController(BaseController):
+    """WelcomeController"""
+    controller_name = "Welcome to Ubuntu"
+
+    def show(self):
+        return WelcomeView(self.finish)
+
+    def finish(self, code, val):
+        raise SystemExit("Saw res: {}, val: {}".format(code, val))

subiquity/palette.py

@@ -18,7 +18,7 @@
 
 def apply_default_colors(cls):
     color_map = {'orange': '#d51',
-                 'light_orange': '#d81',
+                 'light_orange': '#d31',
                  'white': 'white',
                  'black': 'black',
                  'light_aubergine': '#77216F',

subiquity/ui/utils.py

@@ -19,6 +19,40 @@ from urwid import Padding as _Padding
 from functools import partialmethod
 
 
+def apply_padders(cls):
+    """ Decorator for generating useful padding methods
+
+    Loops through and generates methods like:
+
+      Padding.push_1(Widget)
+
+      Sets the left padding attribute by 1
+
+      Padding.pull_24(Widget)
+
+      Sets right padding attribute by 24.
+
+      Padding.center_50(Widget)
+
+      Provides center padding with a relative width of 50
+    """
+    padding_count = 100
+
+    for i in range(1, padding_count):
+        setattr(cls, 'push_{}'.format(i), partialmethod(_Padding, left=i))
+        setattr(cls, 'pull_{}'.format(i), partialmethod(_Padding, right=i))
+        setattr(cls, 'center_{}'.format(i),
+                partialmethod(_Padding, align='center',
+                              width=('relative', i)))
+        setattr(cls, 'left_{}'.format(i),
+                partialmethod(_Padding, align='left',
+                              width=('relative', i)))
+        setattr(cls, 'right_{}'.format(i),
+                partialmethod(_Padding, align='right',
+                              width=('relative', i)))
+    return cls
+
+
+@apply_padders
 class Padding:
-    center = partialmethod(_Padding, align='center',
-                           width=('relative', 50))
+    pass

subiquity/views/__init__.py

@@ -0,0 +1,14 @@
+# Copyright 2015 Canonical, Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

subiquity/views/welcome.py

@@ -13,25 +13,21 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from urwid import (WidgetWrap, ListBox, AttrWrap, Columns, Text,
-                   # emitters
-                   signals, emit_signal)
+from urwid import (WidgetWrap, ListBox, AttrWrap, Columns, Text)
 from subiquity.ui.anchors import Header, Footer, Body  # NOQA
 from subiquity.ui.buttons import confirm_btn, cancel_btn
 from subiquity.ui.utils import Padding
 
 
-class StartView(WidgetWrap):
-    __metaclass__ = signals.MetaSignals
-    signals = ['done']
-
-    def __init__(self):
+class WelcomeView(WidgetWrap):
+    def __init__(self, cb=None):
         Header.title = "SUbiquity - Ubiquity for Servers"
+        self.cb = cb
         self.layout = [
             Header(),
             Text(""),
             Text("Begin the installation", align='center'),
-            Padding.center(self._build_buttons()),
+            Padding.center_50(self._build_buttons()),
             Footer()
         ]
         super().__init__(ListBox(self.layout))
@@ -46,7 +42,11 @@ class StartView(WidgetWrap):
         return Columns(self.buttons)
 
     def confirm(self, button):
-        emit_signal(self, 'done', True)
+        if self.cb is not None:
+            return self.cb(True, 'Moving to next controller.')
 
     def cancel(self, button):
-        emit_signal(self, 'done', False)
+        if self.cb is None:
+            raise SystemExit('Cancelled.')
+        else:
+            return self.cb(False, 'Cancelled with callback.')