1 # Advanced GUI example

     2 

     3 # This nonfunctional sample code is based on a simple application for

     4 # accessing a to-do list.  The details of that particular application

     5 # have been edited out.

     6 #

     7 # Copyright (c) 2005 Nokia Corporation

     8 #

     9 # Licensed under the Apache License, Version 2.0 (the "License");

    10 # you may not use this file except in compliance with the License.

    11 # You may obtain a copy of the License at

    12 #

    13 #     http://www.apache.org/licenses/LICENSE-2.0

    14 #

    15 # Unless required by applicable law or agreed to in writing, software

    16 # distributed under the License is distributed on an "AS IS" BASIS,

    17 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

    18 # See the License for the specific language governing permissions and

    19 # limitations under the License.

    20 

    21 

    22 import e32

    23 import appuifw

    24 

    25 from MyDataAccess import MyDataAccess

    26 

    27 e32.ao_yield()

    28 

    29 def format(item):

    30     # Format the item as a short unicode string.

    31     return u""                          # omitted

    32 

    33 class MyApp:

    34     def __init__(self):

    35         self.lock = e32.Ao_lock()

    36 

    37         self.old_title = appuifw.app.title

    38         appuifw.app.title = u"My Application"

    39 

    40         self.exit_flag = False

    41         appuifw.app.exit_key_handler = self.abort

    42 

    43         self.data = []

    44         appuifw.app.body = appuifw.Listbox([u"Loading..."], self.handle_modify)

    45 

    46         self.menu_add = (u"Add", self.handle_add)

    47         self.menu_del = (u"Delete", self.handle_delete)

    48         appuifw.app.menu = [] # First call to refresh() will fill in the menu.

    49 

    50     def connect(self, host):

    51         self.db = MyDataAccess(host)

    52         self.db.listen(self.notify) # Set up callback for change notifications.

    53 

    54     def loop(self):

    55         try:

    56             self.lock.wait()

    57             while not self.exit_flag:

    58                 self.refresh()

    59                 self.lock.wait()

    60         finally:

    61             self.db.close()

    62 

    63     def close(self):

    64         appuifw.app.menu = []

    65         appuifw.app.body = None

    66         appuifw.app.exit_key_handler = None

    67         appuifw.app.title = self.old_title

    68 

    69     def abort(self):

    70         # Exit-key handler.

    71         self.exit_flag = True

    72         self.lock.signal()

    73 

    74     def notify(self, in_sync):

    75         # Handler for database change notifications.

    76         if in_sync:

    77             self.lock.signal()

    78 

    79     def refresh(self):

    80         # Note selected item.

    81         current_item = self.get_current_item()

    82 

    83         # Get updated data.

    84         self.data = self.db.get_data()

    85 

    86         if not self.data:

    87             content = [u"(Empty)"]

    88         else:

    89             content = [format(item) for item in self.data]

    90 

    91         if current_item in self.data:

    92             # Update the displayed data, retaining the previous selection.

    93             index = self.data.index(current_item)

    94             appuifw.app.body.set_list(content, index)

    95         else:

    96             # Previously selected item is no longer present, so allow

    97             # the selection to be reset.

    98             appuifw.app.body.set_list(content)

    99 

   100         if not self.data:

   101             appuifw.app.menu = [self.menu_add]

   102         else:

   103             appuifw.app.menu = [self.menu_add, self.menu_del]

   104 

   105     def handle_modify(self):

   106         item = self.get_current_item()

   107         if item is not None:

   108             # Display data in Form for user to edit.

   109             # Save modified record in database.

   110             pass                        # omitted

   111 

   112     def handle_add(self):

   113         new_item = self.edit_item(ToDoItem())

   114         if new_item is not None:

   115             # User enters new data into Form.

   116             # Save new record in database.

   117             pass                        # omitted

   118 

   119     def handle_delete(self):

   120         item = self.get_current_item()

   121         if item is not None:

   122             # Remove record from database.

   123             pass                        # omitted

   124 

   125     def get_current_item(self):

   126         # Return currently selected item, or None if the list is empty.

   127         if not self.data:

   128             return None

   129         else:

   130             current = appuifw.app.body.current()

   131             return self.data[current]

   132 

   133 def main():

   134     app = MyApp()

   135     try:

   136         hosts = [u"some.foo.com", u"other.foo.com"]

   137         i = appuifw.popup_menu(hosts, u"Select server:")

   138         if i is not None:

   139             app.connect(hosts[i])

   140             app.loop()

   141     finally:

   142         app.close()

   143 

   144 if __name__ == "__main__":

   145     main()