outlines MVC
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waldek
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@ -2744,6 +2744,576 @@ if __name__ == "__main__":
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## MVC design pattern
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A simple console only MVC.
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We'll add the GUI view in a bit.
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```python
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import wx
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class ConsoleView(object):
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"""A view for console."""
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def select_task(self):
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"""Asks which index to look up."""
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idx = input("which task do you want to see? ")
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return idx
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def show(self, task):
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"""Displays the task to the console. This method is called from the
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controller."""
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print("your task: {}".format(task))
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def error(self, msg):
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"""Prints error messages coming from the controller."""
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print("error: {}".format(msg))
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class WxView(wx.Dialog):
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pass
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class Model(object):
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"""The model houses add data and should implement all methods related to
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adding, modifying and deleting tasks."""
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db = ["go to the shops", "dryhop beer", "drop of motorbike"]
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def get_task(self, idx):
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"""Performs a task lookun into the database and returns it when found.
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If no task is found, it returns an error message that will be displayed
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in the view (via the controller)."""
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try:
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task = Model.db[idx]
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except IndexError:
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task = "task with {} not found!".format(idx)
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return task
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class Controller(object):
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"""Binds the model and the view together."""
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def __init__(self, view):
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self.model = Model()
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self.view = view
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def run(self):
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"""The controller's main function. Depending on what type of view is
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selected, a different event loop is setup. Do note that the ConsoleView
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is not a real event loop, just a basic flow of action."""
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if self.view is ConsoleView:
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self.view = self.view()
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self._run_console_view()
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elif self.view is WxView:
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app = wx.App()
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self.view = self.view()
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self.view._set_controller(self)
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app.MainLoop()
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def get_task_from_model(self, idx):
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"""Needed for the WxView to communicate with the controller."""
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task = self.model.get_task(idx)
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self.view.show_task(task)
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def _run_console_view(self):
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"""Super simple event loop."""
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while True:
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try:
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idx = self.view.select_task()
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idx = int(idx)
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except Exception as e:
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self.view.error(e)
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continue
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task = self.model.get_task(idx)
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self.view.show(task)
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if __name__ == "__main__":
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view = ConsoleView
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# view = WxView
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app = Controller(view)
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app.run()
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```
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And now with the implemented `WxView` class.
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```python
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import wx
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class ConsoleView(object):
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"""A view for console."""
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def select_task(self):
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"""Asks which index to look up."""
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idx = input("which task do you want to see? ")
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return idx
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def show(self, task):
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"""Displays the task to the console. This method is called from the
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controller."""
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print("your task: {}".format(task))
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def error(self, msg):
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"""Prints error messages coming from the controller."""
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print("error: {}".format(msg))
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class WxView(wx.Dialog):
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"""A view using a wx.Dialog window"""
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def __init__(self):
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wx.Dialog.__init__(self, None, title="Task Manager")
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self.panel = wx.Panel(self)
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self.box = wx.BoxSizer(wx.VERTICAL)
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self.task = wx.StaticText(self.panel, label="your task")
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self.idx = wx.SpinCtrl(self.panel)
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self.button = wx.Button(self.panel, label="submit")
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self.button.Bind(wx.EVT_BUTTON, self.select_task)
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self.box.Add(self.task, 0, wx.EXPAND, 1)
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self.box.Add(self.idx, 0, wx.EXPAND, 1)
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self.box.Add(self.button, 0, wx.EXPAND, 1)
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self.panel.SetSizer(self.box)
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self.Show()
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def _set_controller(self, controller):
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"""Set the controller so the view can communicate it's requests to it
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and update it's values too."""
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self.controller = controller
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def select_task(self, event):
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"""Gets the index to look up in the model and submits the request to
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the controller."""
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idx = self.idx.GetValue()
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self.controller.get_task_from_model(idx)
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def show_task(self, task):
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"""Updates the visual label in the view with the task. This method is
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called from the controller."""
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self.task.SetLabel(task)
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class Model(object):
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"""The model houses add data and should implement all methods related to
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adding, modifying and deleting tasks."""
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db = ["go to the shops", "dryhop beer", "drop of motorbike"]
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def get_task(self, idx):
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"""Performs a task lookun into the database and returns it when found.
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If no task is found, it returns an error message that will be displayed
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in the view (via the controller)."""
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try:
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task = Model.db[idx]
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except IndexError:
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task = "task with {} not found!".format(idx)
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return task
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class Controller(object):
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"""Binds the model and the view together."""
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def __init__(self, view):
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self.model = Model()
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self.view = view
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def run(self):
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"""The controller's main function. Depending on what type of view is
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selected, a different event loop is setup. Do note that the ConsoleView
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is not a real event loop, just a basic flow of action."""
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if self.view is ConsoleView:
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self.view = self.view()
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self._run_console_view()
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elif self.view is WxView:
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app = wx.App()
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self.view = self.view()
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self.view._set_controller(self)
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app.MainLoop()
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def get_task_from_model(self, idx):
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"""Needed for the WxView to communicate with the controller."""
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task = self.model.get_task(idx)
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self.view.show_task(task)
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def _run_console_view(self):
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"""Super simple event loop."""
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while True:
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try:
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idx = self.view.select_task()
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idx = int(idx)
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except Exception as e:
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self.view.error(e)
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continue
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task = self.model.get_task(idx)
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self.view.show(task)
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if __name__ == "__main__":
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view = WxView
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app = Controller(view)
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app.run()
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```
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For a GUI only login generator an implementation without MVC could look a bit like this.
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Note that the actual calculation is done inside the window itself.
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This is not a good idea because we should separate responsibilities into classes!
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```python
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import wx
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import login_generator
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class MainWindow(wx.Dialog):
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def __init__(self):
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wx.Dialog.__init__(self, None, title="Login Generator")
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self.full_window = wx.Panel(self)
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self.full_window_sizer = wx.BoxSizer(wx.VERTICAL)
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self.full_window_sizer.Add(self.create_top_panel(), 0, wx.EXPAND | wx.ALL, 20)
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self.full_window_sizer.Add(self.create_bottom_panel(), 0, wx.EXPAND, 0)
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self.full_window.SetSizer(self.full_window_sizer)
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self.Show()
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def create_bottom_panel(self):
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bottom_panel = wx.Panel(self.full_window)
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bottom_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
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self.login_list = wx.ListCtrl(bottom_panel, style=wx.LC_REPORT)
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self.login_list.Bind(wx.EVT_RIGHT_UP, self.show_popup)
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self.login_list.InsertColumn(0, 'username', width=200)
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self.login_list.InsertColumn(1, 'password', width=200)
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bottom_panel_sizer.Add(self.login_list, 0, wx.EXPAND | wx.ALL, 200)
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return bottom_panel
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def create_top_panel(self):
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top_panel = wx.Panel(self.full_window)
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top_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
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self.login_amount = wx.TextCtrl(top_panel)
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self.login_complex = wx.CheckBox(top_panel, label="complex")
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self.login_create = wx.Button(top_panel, label="Create")
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self.login_create.Bind(wx.EVT_BUTTON, self.add_login)
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top_panel_sizer.Add(self.login_amount, 1, wx.EXPAND|wx.ALL,0)
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top_panel_sizer.Add(self.login_complex, 1, wx.EXPAND|wx.ALL,0)
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top_panel_sizer.Add(self.login_create, 1, wx.EXPAND|wx.ALL,0)
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top_panel.SetSizer(top_panel_sizer)
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return top_panel
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def show_popup(self, event):
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menu = wx.Menu()
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menu.Append(1, "Copy selected items")
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menu.Bind(wx.EVT_MENU, self.copy_items, id=1)
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self.PopupMenu(menu)
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def copy_items(self, event):
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selected_items = []
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for i in range(self.login_list.GetItemCount()):
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if self.login_list.IsSelected(i):
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username = selected_items.append(
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self.login_list.GetItem(i, 0).GetText()
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)
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password = selected_items.append(
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self.login_list.GetItem(i, 1).GetText()
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)
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clipdata = wx.TextDataObject()
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clipdata.SetText("\n".join(selected_items))
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wx.TheClipboard.Open()
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wx.TheClipboard.SetData(clipdata)
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wx.TheClipboard.Close()
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def add_login(self, event):
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amount = self.login_amount.GetValue()
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complex = self.login_complex.GetValue()
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try:
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amount = int(amount)
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except:
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amount = 1
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for i in range(0, amount):
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username = login_generator.generate_username()
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password = login_generator.generate_password(12, complex)
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index = self.login_list.InsertItem(0, username)
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self.login_list.SetItem(index, 1, password)
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if __name__ == "__main__":
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app = wx.App()
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win = MainWindow()
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app.MainLoop()
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```
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Now let's assume the generate username and password function take some calculation time.
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We'll add in a fake `time.sleep` to simulate.
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```python
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import wx
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import login_generator
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import time
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class MainWindow(wx.Dialog):
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def __init__(self):
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wx.Dialog.__init__(self, None, title="Login Generator")
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self.full_window = wx.Panel(self)
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self.full_window_sizer = wx.BoxSizer(wx.VERTICAL)
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self.full_window_sizer.Add(self.create_top_panel(), 0, wx.EXPAND | wx.ALL, 20)
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self.full_window_sizer.Add(self.create_bottom_panel(), 0, wx.EXPAND, 0)
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self.full_window.SetSizer(self.full_window_sizer)
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self.Show()
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def create_bottom_panel(self):
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bottom_panel = wx.Panel(self.full_window)
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bottom_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
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self.login_list = wx.ListCtrl(bottom_panel, style=wx.LC_REPORT)
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self.login_list.Bind(wx.EVT_RIGHT_UP, self.show_popup)
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self.login_list.InsertColumn(0, 'username', width=200)
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self.login_list.InsertColumn(1, 'password', width=200)
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bottom_panel_sizer.Add(self.login_list, 0, wx.EXPAND | wx.ALL, 200)
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return bottom_panel
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def create_top_panel(self):
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top_panel = wx.Panel(self.full_window)
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top_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
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self.login_amount = wx.TextCtrl(top_panel)
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self.login_complex = wx.CheckBox(top_panel, label="complex")
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self.login_create = wx.Button(top_panel, label="Create")
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self.login_create.Bind(wx.EVT_BUTTON, self.add_login)
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top_panel_sizer.Add(self.login_amount, 1, wx.EXPAND|wx.ALL,0)
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top_panel_sizer.Add(self.login_complex, 1, wx.EXPAND|wx.ALL,0)
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top_panel_sizer.Add(self.login_create, 1, wx.EXPAND|wx.ALL,0)
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top_panel.SetSizer(top_panel_sizer)
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return top_panel
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def show_popup(self, event):
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menu = wx.Menu()
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menu.Append(1, "Copy selected items")
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menu.Bind(wx.EVT_MENU, self.copy_items, id=1)
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self.PopupMenu(menu)
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def copy_items(self, event):
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selected_items = []
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for i in range(self.login_list.GetItemCount()):
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if self.login_list.IsSelected(i):
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username = selected_items.append(
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self.login_list.GetItem(i, 0).GetText()
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)
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password = selected_items.append(
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self.login_list.GetItem(i, 1).GetText()
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)
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clipdata = wx.TextDataObject()
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clipdata.SetText("\n".join(selected_items))
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wx.TheClipboard.Open()
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wx.TheClipboard.SetData(clipdata)
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wx.TheClipboard.Close()
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def add_login(self, event):
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amount = self.login_amount.GetValue()
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complex_bool = self.login_complex.GetValue()
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try:
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amount = int(amount)
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except:
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amount = 1
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for i in range(0, amount):
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username = login_generator.generate_username()
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password = login_generator.generate_password(12, complex_bool)
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time.sleep(1)
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index = self.login_list.InsertItem(0, username)
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self.login_list.SetItem(index, 1, password)
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if __name__ == "__main__":
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app = wx.App()
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win = MainWindow()
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app.MainLoop()
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```
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A clear separation of responsabilities can be acchieved via an MVC pattern and a login *library*.
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The library code is quite straightforward and goes as follows.
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It's basically the same code we did before but with added `try except` blocks.
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Can you tell me why I added those?
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```python
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import random
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import string
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def load_file(filename):
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"""
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We load a file and make a list out of it. Note that the same function is
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used for both files (both adjectives and subjects). Functions should be
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made as generic as possible.
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There IS a problem you can fix, some logins will have spaces in them. Try
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to remove them in this function!
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"""
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words = []
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with open(filename, "r") as fp:
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lines = fp.readlines()
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for line in lines:
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words.append(line.strip()) # what does strip() do, what does append() do? remember CTRL+Q!
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return words
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def generate_username():
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"""
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We'll generate a random pair of adjectives and subjects from two wordlists.
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You NEED to have both files in you python project for this to work! Note
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the capitalize method call to make it all prettier...
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"""
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try:
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adjectives = load_file("./adjectives.txt")
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except:
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adjectives = ["big", "funny", "normal", "red"]
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try:
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subjects = load_file("./subjects.txt")
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except:
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subjects = ["giraffe", "elephant", "cougar", "tiger"]
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adjective = random.choice(adjectives)
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subject = random.choice(subjects)
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username = adjective.capitalize() + subject.capitalize()
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return username
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def generate_password(length=10, complictated=True):
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"""
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We generate a password with default settings. You can overide these by
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changing the arguments in the function call.
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"""
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password = ""
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if complictated:
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chars = string.ascii_letters + string.digits + string.punctuation
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else:
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chars = string.ascii_letters
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for i in range(0, length):
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password += random.choice(chars)
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return password
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if __name__ == "__main__":
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# let's do some testing!
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username_test = generate_username()
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print(username_test)
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password_test = generate_password()
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print(password_test)
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```
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And now the GUI code nicely split up in a **model**, **controller** and a **view**.
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The overhead is quite large but it makes the code a lot more scalable.
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```python
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import wx
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import login_generator
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import time
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import threading
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import queue
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class View(wx.Dialog):
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def __init__(self, controller):
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wx.Dialog.__init__(self, None, title="Login Generator")
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self.controller = controller
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self.full_window = wx.Panel(self)
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self.full_window_sizer = wx.BoxSizer(wx.VERTICAL)
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self.full_window_sizer.Add(self.create_top_panel(), 0, wx.EXPAND | wx.ALL, 20)
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self.full_window_sizer.Add(self.create_bottom_panel(), 0, wx.EXPAND, 0)
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self.full_window.SetSizer(self.full_window_sizer)
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self.Show()
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def create_bottom_panel(self):
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bottom_panel = wx.Panel(self.full_window)
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bottom_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
|
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self.login_list = wx.ListCtrl(bottom_panel, style=wx.LC_REPORT)
|
||||
self.login_list.Bind(wx.EVT_RIGHT_UP, self.show_popup)
|
||||
self.login_list.InsertColumn(0, 'username', width=200)
|
||||
self.login_list.InsertColumn(1, 'password', width=200)
|
||||
bottom_panel_sizer.Add(self.login_list, 0, wx.EXPAND | wx.ALL, 200)
|
||||
return bottom_panel
|
||||
|
||||
def create_top_panel(self):
|
||||
top_panel = wx.Panel(self.full_window)
|
||||
top_panel_sizer = wx.BoxSizer(wx.HORIZONTAL)
|
||||
self.login_amount = wx.TextCtrl(top_panel)
|
||||
self.login_complex = wx.CheckBox(top_panel, label="complex")
|
||||
self.login_create = wx.Button(top_panel, label="Create")
|
||||
self.login_create.Bind(wx.EVT_BUTTON, self.submit_request)
|
||||
top_panel_sizer.Add(self.login_amount, 1, wx.EXPAND|wx.ALL,0)
|
||||
top_panel_sizer.Add(self.login_complex, 1, wx.EXPAND|wx.ALL,0)
|
||||
top_panel_sizer.Add(self.login_create, 1, wx.EXPAND|wx.ALL,0)
|
||||
top_panel.SetSizer(top_panel_sizer)
|
||||
return top_panel
|
||||
|
||||
def show_popup(self, event):
|
||||
menu = wx.Menu()
|
||||
menu.Append(1, "Copy selected items")
|
||||
menu.Bind(wx.EVT_MENU, self.copy_items, id=1)
|
||||
self.PopupMenu(menu)
|
||||
|
||||
def copy_items(self, event):
|
||||
selected_items = []
|
||||
for i in range(self.login_list.GetItemCount()):
|
||||
if self.login_list.IsSelected(i):
|
||||
username = selected_items.append(
|
||||
self.login_list.GetItem(i, 0).GetText()
|
||||
)
|
||||
password = selected_items.append(
|
||||
self.login_list.GetItem(i, 1).GetText()
|
||||
)
|
||||
clipdata = wx.TextDataObject()
|
||||
clipdata.SetText("\n".join(selected_items))
|
||||
wx.TheClipboard.Open()
|
||||
wx.TheClipboard.SetData(clipdata)
|
||||
wx.TheClipboard.Close()
|
||||
|
||||
def submit_request(self, event):
|
||||
amount = self.login_amount.GetValue()
|
||||
complex_bool = self.login_complex.GetValue()
|
||||
try:
|
||||
amount = int(amount)
|
||||
except:
|
||||
amount = 1
|
||||
self.controller.get_new_logins(amount, complex_bool)
|
||||
|
||||
def update_logins(self, login):
|
||||
username, password = login
|
||||
index = self.login_list.InsertItem(0, username)
|
||||
self.login_list.SetItem(index, 1, password)
|
||||
|
||||
|
||||
class Controller(object):
|
||||
def __init__(self):
|
||||
self.app = wx.App()
|
||||
self.view = View(self)
|
||||
self.model = Model(self)
|
||||
|
||||
def get_new_logins(self, amount, complex_bool):
|
||||
self.model.generate_login(amount, complex_bool)
|
||||
|
||||
def set_new_logins(self, logins):
|
||||
self.view.update_logins(logins)
|
||||
|
||||
|
||||
class Model(threading.Thread):
|
||||
def __init__(self, controller):
|
||||
threading.Thread.__init__(self, target=self.main)
|
||||
self.controller = controller
|
||||
self.queue = queue.Queue()
|
||||
self.start()
|
||||
|
||||
def main(self):
|
||||
while True:
|
||||
amount, complex_bool = self.queue.get()
|
||||
username = login_generator.generate_username()
|
||||
password = login_generator.generate_password(12, complex_bool)
|
||||
logins = (username, password)
|
||||
self.controller.set_new_logins(logins)
|
||||
time.sleep(1)
|
||||
|
||||
def generate_login(self, amount, complex_bool):
|
||||
for i in range(0, amount):
|
||||
self.queue.put((amount, complex_bool))
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
mvc = Controller()
|
||||
mvc.app.MainLoop()
|
||||
```
|
||||
|
||||
# Coding challenge - Login generator with GUI
|
||||
|
||||
# Coding challenge - Trivial pursuit with GUI
|
||||
|
|
|
|||
Loading…
Reference in New Issue