# Advanced GUI example

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

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

# have been edited out.

#

# Copyright (c) 2005 Nokia Corporation

#

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

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

# You may obtain a copy of the License at

#

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

#

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

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

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

# See the License for the specific language governing permissions and

# limitations under the License.

import e32

import appuifw

from MyDataAccess import MyDataAccess

e32.ao_yield()

def format(item):

    # Format the item as a short unicode string.

    return u""                          # omitted

class MyApp:

    def __init__(self):

        self.lock = e32.Ao_lock()

        self.old_title = appuifw.app.title

        appuifw.app.title = u"My Application"

        self.exit_flag = False

        appuifw.app.exit_key_handler = self.abort

        self.data = []

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

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

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

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

    def connect(self, host):

        self.db = MyDataAccess(host)

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

    def loop(self):

        try:

            self.lock.wait()

            while not self.exit_flag:

                self.refresh()

                self.lock.wait()

        finally:

            self.db.close()

    def close(self):

        appuifw.app.menu = []

        appuifw.app.body = None

        appuifw.app.exit_key_handler = None

        appuifw.app.title = self.old_title

    def abort(self):

        # Exit-key handler.

        self.exit_flag = True

        self.lock.signal()

    def notify(self, in_sync):

        # Handler for database change notifications.

        if in_sync:

            self.lock.signal()

    def refresh(self):

        # Note selected item.

        current_item = self.get_current_item()

        # Get updated data.

        self.data = self.db.get_data()

        if not self.data:

            content = [u"(Empty)"]

        else:

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

        if current_item in self.data:

            # Update the displayed data, retaining the previous selection.

            index = self.data.index(current_item)

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

        else:

            # Previously selected item is no longer present, so allow

            # the selection to be reset.

            appuifw.app.body.set_list(content)

        if not self.data:

            appuifw.app.menu = [self.menu_add]

        else:

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

    def handle_modify(self):

        item = self.get_current_item()

        if item is not None:

            # Display data in Form for user to edit.

            # Save modified record in database.

            pass                        # omitted

    def handle_add(self):

        new_item = self.edit_item(ToDoItem())

        if new_item is not None:

            # User enters new data into Form.

            # Save new record in database.

            pass                        # omitted

    def handle_delete(self):

        item = self.get_current_item()

        if item is not None:

            # Remove record from database.

            pass                        # omitted

    def get_current_item(self):

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

        if not self.data:

            return None

        else:

            current = appuifw.app.body.current()

            return self.data[current]

def main():

    app = MyApp()

    try:

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

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

        if i is not None:

            app.connect(hosts[i])

            app.loop()

    finally:

        app.close()

if __name__ == "__main__":

    main()