Introduction
This recipe provides a small app that demonstrates some of the basics of using a wx.StaticBitmap, particularly how to change the bitmap displayed.
What Objects are Involved
wx.StaticBitmap
- The main point of this recipe
wx.Image
- Used to load images of various types: JPEG etc.
wx.Bitmap
The native bitmap type used to draw stuff to the screen: needed to put a bitmap on wx.StaticBitmap
Process Overview
The recipe puts a wx.StaticBitmap on a wx.Frame and provides a wx.Button that changes the image.
Special Concerns
- Tested on OS-X with Python2.5 and wxPython 2.8, but it is little changed form older versions that worked on 2.5.*
- NOTE: There have been reports that it works on Linux and Windows as well.
- You need to create a directory called "Images" with at least one jpeg in it.
Code Sample
"""
Simple app that demonstrates how to use a wx.StaticBitmap, specifically
replacing bitmap dynamically.
Note: there needs to be an "Images" directory with one or more jpegs in it in the
current working directory for this to work
Test most recently on OS-X wxPython 2.9.3.1
But it been reported to work on lots of other platforms/versions
"""
import wx, os
class TestFrame(wx.Frame):
def __init__(self, *args, **kwargs):
wx.Frame.__init__(self, *args, **kwargs)
# there needs to be an "Images" directory with one or more jpegs in it in the
# current working directory for this to work
self.jpgs = GetJpgList("./Images") # get all the jpegs in the Images directory
self.CurrentJpg = 0
self.MaxImageSize = 200
b = wx.Button(self, -1, "Display next")
b.Bind(wx.EVT_BUTTON, self.DisplayNext)
# starting with an EmptyBitmap, the real one will get put there
# by the call to .DisplayNext()
self.Image = wx.StaticBitmap(self, bitmap=wx.EmptyBitmap(self.MaxImageSize, self.MaxImageSize))
self.DisplayNext()
# Using a Sizer to handle the layout: I never use absolute positioning
box = wx.BoxSizer(wx.VERTICAL)
box.Add(b, 0, wx.CENTER | wx.ALL,10)
# adding stretchable space before and after centers the image.
box.Add((1,1),1)
box.Add(self.Image, 0, wx.ALIGN_CENTER_HORIZONTAL | wx.ALL | wx.ADJUST_MINSIZE, 10)
box.Add((1,1),1)
self.SetSizerAndFit(box)
wx.EVT_CLOSE(self, self.OnCloseWindow)
def DisplayNext(self, event=None):
# load the image
Img = wx.Image(self.jpgs[self.CurrentJpg], wx.BITMAP_TYPE_JPEG)
# scale the image, preserving the aspect ratio
W = Img.GetWidth()
H = Img.GetHeight()
if W > H:
NewW = self.MaxImageSize
NewH = self.MaxImageSize * H / W
else:
NewH = self.MaxImageSize
NewW = self.MaxImageSize * W / H
Img = Img.Scale(NewW,NewH)
# convert it to a wx.Bitmap, and put it on the wx.StaticBitmap
self.Image.SetBitmap(wx.BitmapFromImage(Img))
# You can fit the frame to the image, if you want.
#self.Fit()
#self.Layout()
self.Refresh()
self.CurrentJpg += 1
if self.CurrentJpg > len(self.jpgs) -1:
self.CurrentJpg = 0
def OnCloseWindow(self, event):
self.Destroy()
def GetJpgList(dir):
jpgs = [f for f in os.listdir(dir) if f[-4:] == ".jpg"]
# print "JPGS are:", jpgs
return [os.path.join(dir, f) for f in jpgs]
class App(wx.App):
def OnInit(self):
frame = TestFrame(None, -1, "wxBitmap Test", wx.DefaultPosition,(550,200))
self.SetTopWindow(frame)
frame.Show(True)
return True
if __name__ == "__main__":
app = App(0)
app.MainLoop()
Comments
Please test this out on other platforms and/versions. If it doesn't work find a fix and correct it here, or send me a note:
Acknowledgments
Change due to wx API( newer wxPython include a wx.Window.MaxSize attribute. Found and corrected by Ross Marsden
Tested Platfroms/Versions
OS-X: wxPython 2.9.3.1 (Cocoa)
- wxPython 2.8.12.1 (Carbon)
Windows:
WindowsXP: wxPython 2.8.12.1