Question

So I have a wx.Frame to which I add a GLCanvas and some buttons. Here is the part that ads these:

self.sizer = wx.FlexGridSizer(2,2,20,20)
        self.xSize = FRAME_WIDTH - MIN_BUT_SIZE
        self.ySize = FRAME_HEIGHT - 40
        self.canvas = myGLCanvas(self, size=(self.xSize, self.ySize))
        self.panel = GLPanel(self, canvas=self.canvas)
        self.sizer.Add(self.canvas, 1, wx.EXPAND)
        self.sizer.Add(self.panel, 0, wx.EXPAND)
        self.headerSizer.DeleteWindows()
        self.centerSizer.Remove(self.headerSizer)
        self.Layout()
        self.centerSizer.Add(self.sizer)
        self.goBack = wx.Button(self, -1, str("Go Back!"))
        self.sizer.Add(self.goBack, 0, wx.ALIGN_CENTER_HORIZONTAL, 2)
        self.sizer.Add((20,20))
        self.SetSizerAndFit(self.mainGrid)
        self.Bind(wx.EVT_SIZING, self.OnSizing) 

I have to mention here that self.centerSizer is already added to self.mainGrid at this point along with another sizer that I user for some buttons. Now if I use self.SetSizer(mainGrid) instead of SetSizerAndFit(), the components I added in the above code are not positioned properly UNTIL I resize my frame manually. With SetSizerAndFit this works. But now I want my gl canvas to resize with my frame. So my approach is:

def OnSizing(self, event):
    size = self.GetSize()       
    newCanvasXSize = size.GetWidth() - MIN_BUT_SIZE
    newCanvasYSize = size.GetHeight() - 40
    self.canvas.SetSize((newCanvasXSize, newCanvasYSize))
    self.Layout()

However this doesnt work and my canvas stays the same size as before. I’ve read somewhere that SetSizerAndFit also sets the min_size and that is why resizing doesnt work with it. However, even if I leave it with SetSizer, and resize the frame so everything is positioned properly, the resizing of the canvas doesnt work. Deleting and creating the GLCanvas is not and option here since it takes quite some time to load my vertices.

EDIT

Ok using SetSizer + Layout gets the positioning done. However the Canvas still doesnt resize properly. I have a OnResize binded to EVT_SIZE in the canvas that does:

def OnResize(self, e):
    self.width, self.height = e.GetSize()
    self.SetSize((self.width, self.height))
    self.Layout()

I printed the self.width and self.height here to see what happens. The display is like this:

875 674 — (these are the values that are correct, but immediately after followed by)
640 520 — (these are the default values the Canvas was created with)

This patters repeats itself for every resize.

EDIT2

Ok the above behaviour was because I still had a SetSizerAndFit in a part of my program. If I go for a pure SetSizer + Layout approach this is what happens. The components ( my GLCanvas and 3 other buttons) are added to the frame in their corresponding locations. However:
1.The frame is not resized to the needed size so my buttons are somewhere outside the frame.
2.The GLCanvas is positioned but it doesnt display anything UNTIL I do a resize event myself.

3.Maybe not dirrectly connected but it is possible to decrease min size? I’m asking because if I use SetMinSize() in the Resize handler on the canvas it resizes ONLY WHEN the size increases. If frame size decreases the canvas remains with the old(larger) min size.

EDIT3

Ok after some tweaking I managed to get my canvas to resize with the frame. But now I have another problem, I have a flex grid sizer with one canvas, and three buttons that looks like this:

http://postimage.org/image/1cyhqqcck/

Now I’ve managed to make my canvas resize with the frame, however the Points, Triangle and Go Back buttons stay on the same position when resizing and the canvas just covers them up. I’ve called Layout() with no appearent effect.

Answer 1

As I recall, even Robin Dunn (creator of wxPython) doesn’t use SetSizerAndFit. If you can get the stuff positioned properly when you change the frame size slightly, then you only need to call the frame’s Layout() method. That might be all you need to call to solve the GLCanvas part too. To recap, skip SetSizerAndFit and just use SetSizer.