ImageTk.Photoimage not displayed

2008-08-28 Thread harryos
hi
i am trying to display an image on a canvas in a gui made with Tkinter
widgets


class PhotoDisplay:
def __init__(self,parent):
self.mainframe = Frame(parent,background=grey)
.
#added a subframe to hold canvas and button

   self.canvFrame=Frame(self.mainframe,...)
   
   self.mycanvas=Canvas(self.canvFrame,...)
   ...

def okbuttonClick(self):
self.mycanvas.delete(ALL)
myimagename=...#get an imagefilename from somewhere..
self.showSelectedImage(myimagename)

def showSelectedImage(self,imageName):
myimg=ImageTk.PhotoImage(file=imageName)
imgtag=self.mycanvas.create_image(70,100,image=myimg)
self.mycanvas.update_idletasks()


when i click the button ,the image is displayed for a fraction of a
second on the canvas and disappears.I couldn't figure out why this is
happening.I am quite new to Tkinter and still going  thru Fredrik
Lundh's intro to tkinter..can someone tell me if i am doing sthing
wrong here?
thanks in advance
harry
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Re: ImageTk.Photoimage not displayed

2008-08-28 Thread Guilherme Polo
On Thu, Aug 28, 2008 at 4:07 PM, harryos [EMAIL PROTECTED] wrote:
 hi
 i am trying to display an image on a canvas in a gui made with Tkinter
 widgets


 class PhotoDisplay:
def __init__(self,parent):
self.mainframe = Frame(parent,background=grey)
.
#added a subframe to hold canvas and button

   self.canvFrame=Frame(self.mainframe,...)
   
   self.mycanvas=Canvas(self.canvFrame,...)
   ...

def okbuttonClick(self):
self.mycanvas.delete(ALL)
myimagename=...#get an imagefilename from somewhere..
self.showSelectedImage(myimagename)

def showSelectedImage(self,imageName):
myimg=ImageTk.PhotoImage(file=imageName)
imgtag=self.mycanvas.create_image(70,100,image=myimg)
self.mycanvas.update_idletasks()


 when i click the button ,the image is displayed for a fraction of a
 second on the canvas and disappears.I couldn't figure out why this is
 happening.I am quite new to Tkinter and still going  thru Fredrik
 Lundh's intro to tkinter..can someone tell me if i am doing sthing
 wrong here?

You have to keep a reference to these images you are creating,
otherwise as soon as those methods finishes they are gone.

 thanks in advance
 harry
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 http://mail.python.org/mailman/listinfo/python-list




-- 
-- Guilherme H. Polo Goncalves
--
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