wxWidgets/wxPython/samples/doodle/doodle.py

# doodle.py

"""
This module contains the DoodleWindow class which is a window that you
can do simple drawings upon.
"""


from wxPython.wx import *

#----------------------------------------------------------------------

class DoodleWindow(wxWindow):
    menuColours = { 100 : 'Black',
                    101 : 'Yellow',
                    102 : 'Red',
                    103 : 'Green',
                    104 : 'Blue',
                    105 : 'Purple',
                    106 : 'Brown',
                    107 : 'Aquamarine',
                    108 : 'Forest Green',
                    109 : 'Light Blue',
                    110 : 'Goldenrod',
                    111 : 'Cyan',
                    112 : 'Orange',
                    113 : 'Navy',
                    114 : 'Dark Grey',
                    115 : 'Light Grey',
                    }
    maxThickness = 16


    def __init__(self, parent, ID):
        wxWindow.__init__(self, parent, ID)
        self.SetBackgroundColour(wxWHITE)
        self.listeners = []
        self.thickness = 1
        self.SetColour("Black")
        self.lines = []
        self.x = self.y = 0
        self.MakeMenu()

        # hook some mouse events
        EVT_LEFT_DOWN(self, self.OnLeftDown)
        EVT_LEFT_UP(self, self.OnLeftUp)
        EVT_RIGHT_UP(self, self.OnRightUp)
        EVT_MOTION(self, self.OnMotion)

        # and the refresh event
        EVT_PAINT(self, self.OnPaint)


    def __del__(self):
        self.menu.Destroy()


    def SetColour(self, colour):
        """Set a new colour and make a matching pen"""
        self.colour = colour
        self.pen = wxPen(wxNamedColour(self.colour), self.thickness, wxSOLID)
        self.Notify()


    def SetThickness(self, num):
        """Set a new line thickness and make a matching pen"""
        self.thickness = num
        self.pen = wxPen(wxNamedColour(self.colour), self.thickness, wxSOLID)
        self.Notify()


    def GetLinesData(self):
        return self.lines[:]


    def SetLinesData(self, lines):
        self.lines = lines[:]
        self.Refresh()


    def MakeMenu(self):
        """Make a menu that can be popped up later"""
        menu = wxMenu()
        keys = self.menuColours.keys()
        keys.sort()
        for k in keys:
            text = self.menuColours[k]
            menu.Append(k, text, checkable=true)
        EVT_MENU_RANGE(self, 100, 200, self.OnMenuSetColour)
        EVT_UPDATE_UI_RANGE(self, 100, 200, self.OnCheckMenuColours)
        menu.Break()

        for x in range(1, self.maxThickness+1):
            menu.Append(x, str(x), checkable=true)
        EVT_MENU_RANGE(self, 1, self.maxThickness, self.OnMenuSetThickness)
        EVT_UPDATE_UI_RANGE(self, 1, self.maxThickness, self.OnCheckMenuThickness)
        self.menu = menu


    # These two event handlers are called before the menu is displayed
    # to determine which items should be checked.
    def OnCheckMenuColours(self, event):
        text = self.menuColours[event.GetId()]
        if text == self.colour:
            event.Check(true)
        else:
            event.Check(false)
    def OnCheckMenuThickness(self, event):
        if event.GetId() == self.thickness:
            event.Check(true)
        else:
            event.Check(false)


    def OnLeftDown(self, event):
        """called when the left mouse button is pressed"""
        self.curLine = []
        self.x, self.y = event.GetPositionTuple()
        self.CaptureMouse()


    def OnLeftUp(self, event):
        """called when the left mouse button is released"""
        self.lines.append( (self.colour, self.thickness, self.curLine) )
        self.curLine = []
        self.ReleaseMouse()


    def OnRightUp(self, event):
        """called when the right mouse button is released, will popup the menu"""
        pt = event.GetPosition()
        self.PopupMenu(self.menu, pt)



    def OnMotion(self, event):
        """
        Called when the mouse is in motion.  If the left button is
        dragging then draw a line from the last event position to the
        current one.  Save the coordinants for redraws.
        """
        if event.Dragging() and event.LeftIsDown():
            dc = wxClientDC(self)
            dc.BeginDrawing()
            dc.SetPen(self.pen)
            pos = event.GetPositionTuple()
            coords = (self.x, self.y) + pos
            self.curLine.append(coords)
            dc.DrawLine(self.x, self.y, pos[0], pos[1])
            self.x, self.y = pos
            dc.EndDrawing()


    def OnPaint(self, event):
        """
        Called when the window is exposed.  Redraws all the lines that have
        been drawn already.
        """
        dc = wxPaintDC(self)
        dc.BeginDrawing()
        for colour, thickness, line in self.lines:
            pen = wxPen(wxNamedColour(colour), thickness, wxSOLID)
            dc.SetPen(pen)
            for coords in line:
                apply(dc.DrawLine, coords)
        dc.EndDrawing()


    # Event handlers for the popup menu, uses the event ID to determine
    # the colour or the thickness to set.
    def OnMenuSetColour(self, event):
        self.SetColour(self.menuColours[event.GetId()])

    def OnMenuSetThickness(self, event):
        self.SetThickness(event.GetId())


    # Observer pattern.  Listeners are registered and then notified
    # whenever doodle settings change.
    def AddListener(self, listener):
        self.listeners.append(listener)

    def Notify(self):
        for other in self.listeners:
            other.Update(self.colour, self.thickness)


#----------------------------------------------------------------------

class DoodleFrame(wxFrame):
    def __init__(self, parent):
        wxFrame.__init__(self, parent, -1, "Doodle Frame", size=(800,600))
        self.doodle = DoodleWindow(self, -1)


#----------------------------------------------------------------------

if __name__ == '__main__':
    app = wxPySimpleApp()
    frame = DoodleFrame(None)
    frame.Show(true)
    app.MainLoop()