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Issue with Display of wxFrame

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Englishuk:

--- Quote from: seb_seb0 on May 01, 2010, 11:16:42 am ---Well, your topic will be locked because it is a wxWidgets question, and not a CodeBlocks question

Your problem comes certainly from the panel paint handler

--- Code: ---void MainFrame::OnPanel1Paint(wxPaintEvent& event)
--- End code ---

and from the event connector:

--- Code: ---Panel1->Connect(ID_PANEL1,wxEVT_PAINT,(wxObjectEventFunction)&MainFrame::OnPanel1Paint,0,this);
--- End code ---

There are 2 mistakes in these 2 lines:
  1 - the wxEVT_PAINT handling is not needed - wxPanel manages it internally
  2 - you are doing nothing in the event handler (empty function). On windows (I assume you are on Windows, seeing your screenshots), you MUST create a wxPaintDC object in the paint handler, even if you do not use it. Otherwise, Windows will keep asking to update the panel, making an infinite loop. I bet that when you run your program, your CPU usage is near 100%
       this infinite loop prevents the child window from the panel being repainted - hence you have 4 nice black rectangles on your window.

Everything is in the wxWidgets doc. You should read them.

Regards,

Sebastien

--- End quote ---

You Sir are a star!

I installed code::blocks on Ubuntu, got a helloworld app going with wxsmith. Setup code::blocks for cross compile for win32 using mingw32 (which I must say is not easy to do for a newbie).

Compiled my program for win32, and was seeing 100% cpu usage using wine and also on native Windows.

For anyone else who is using the wxsmith helloworld tutorial, I commented out the following line:

//Panel1->Connect(wxEVT_PAINT,(wxObjectEventFunction)&HelloApp2Frame::OnPanel1Paint,0,this);

Located in Main.cpp

Further down, I commented out the following block of code:

//void HelloApp2Frame::OnPanel1Paint(wxPaintEvent& event)
//{
 //   wxPaintDC dc(this);
//}

Many thanks to the original poster for asking the question and for Sebastien who correctly identified how this issue presents itsself in Windows.

The only issue now is every time I change by frame/panel, the first line above is uncommented and I have to re-comment it before compiling.

Why am I posting? Just in case it helps someone else resolve the same issue...........

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