Question

我正在使用C ++（特别是使用wxWidget）来调用用wxPython编写的一些代码或模块。我的工具是Visual Studio 2010，Python2.7和wxPython2.8.11。

但我遇到两个问题。第一个问题是无法找到相关的教程。第二个问题是我找到了一些代码，在这段代码中（代码如下），使用了一个名为wxPyMake_wxObject()的函数。但是当调用该函数时，会发生异常并且错误消息是

0x00ea7a35处有未经处理的异常：0xC0000005：读取位置0x00000000时发生访问冲突

（英文是：TestWxWidget2.exe中的0x00ea7a35中的未处理异常：0xC0000005：访问冲突读取位置0x00000000）。 The screenshot of the error messages

我希望有人能够帮我解决这个问题。因为我被这个例外困惑了两个星期。非常感谢你！我在找你的回复！

#include <Python.h>
// For compilers that support precompilation, includes "wx/wx.h".
#include <wx/wxprec.h>
#ifdef __BORLANDC__
#pragma hdrstop
#endif

#ifndef WX_PRECOMP
#include <wx/wx.h>
#endif
#include <wx/splitter.h>
#if defined(__WXGTK__) || defined(__WXMOTIF__) || defined(__WXMAC__) || defined(__WXMGL__)
#include "mondrian.xpm"
#endif
// Import Python and wxPython headers
#include <wx/wxPython/wxPython.h>
#pragma comment(linker, "\"/manifestdependency:type='win32' name='Microsoft.VC90.CRT' version='9.0.21022.8' processorArchitecture='x86' publicKeyToken='1fc8b3b9a1e18e3b' language='*'\"")
#ifdef _DEBGU
#pragma comment(lib, "python27_d.lib")
#else
#pragma comment(lib, "python27.lib")
#endif
// Class definitions
class MyApp : public wxApp
{
public:
    virtual bool OnInit();
    virtual int OnExit();
    bool Init_wxPython();
private:
    PyThreadState* m_mainTState;
};
class MyFrame : public wxFrame
{
public:
    MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
    void RedirectStdio();
    wxWindow* DoPythonStuff(wxWindow* parent);
    void OnExit(wxCommandEvent& event);
    void OnPyFrame(wxCommandEvent& event);
private:
    DECLARE_EVENT_TABLE()
};
//----------------------------------------------------------------------
// MyApp methods
bool MyApp::OnInit()
{
    if ( !Init_wxPython() )
        // don't start the app if we can't initialize wxPython.
        return false;
    MyFrame *frame = new MyFrame(_T("Embedded wxPython Test"), wxDefaultPosition, wxSize(700, 600));
    frame->Show(true);
    return true;
}
bool MyApp::Init_wxPython()
{
    // Initialize Python
    Py_Initialize();
    PyEval_InitThreads();
    // Load the wxPython core API. Imports the wx._core_ module and sets a local pointer to a function table
    // located there. The pointer is used internally by the rest of the API functions.
    if ( ! wxPyCoreAPI_IMPORT() ) {
        wxLogError(wxT("***** Error importing the wxPython API! *****"));
        PyErr_Print();
        Py_Finalize();
        return false;
    }       
    // Save the current Python thread state and release the Global Interpreter Lock.
    m_mainTState = wxPyBeginAllowThreads();
    return true;
}
int MyApp::OnExit()
{
    // Restore the thread state and tell Python to cleanup after itself. wxPython will do its own cleanup as part
    // of that process. This is done in OnExit instead of ~MyApp because OnExit is only called if OnInit is successful.
    wxPyEndAllowThreads(m_mainTState);
    Py_Finalize();
    return 0;   
}
IMPLEMENT_APP(MyApp)
    //----------------------------------------------------------------------
enum{
    ID_EXIT=1001,
    ID_PYFRAME
};
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
    EVT_MENU(ID_EXIT,      MyFrame::OnExit)
    EVT_MENU(ID_PYFRAME,   MyFrame::OnPyFrame)
END_EVENT_TABLE()
MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
    : wxFrame(NULL, -1, title, pos, size, wxDEFAULT_FRAME_STYLE|wxNO_FULL_REPAINT_ON_RESIZE)
{
    SetIcon(wxICON(mondrian));
    wxMenuBar* mbar = new wxMenuBar;
    wxMenu*    menu = new wxMenu;
    menu->Append(ID_PYFRAME, _T("Make wx&Python frame"));
    menu->AppendSeparator();
    menu->Append(ID_EXIT, _T("&Close Frame\tAlt-X"));
    mbar->Append(menu, _T("&File"));
    SetMenuBar(mbar);
    CreateStatusBar();
    RedirectStdio();
    // Make some child windows from C++
    wxSplitterWindow* sp = new wxSplitterWindow(this, -1);
    wxPanel* p1 = new wxPanel(sp, -1, wxDefaultPosition, wxDefaultSize, wxSUNKEN_BORDER);
    new wxStaticText(p1, -1, _T("The frame, menu, splitter, this panel and this text were created in C++..."),
        wxPoint(10,10));
    // And get a panel from Python
    wxWindow* p2 = DoPythonStuff(sp);
    if (p2)
        sp->SplitHorizontally(p1, p2, GetClientSize().y/4);
}
void MyFrame::OnExit(wxCommandEvent& event)
{
    Close();
}
// This is where the fun begins...
char* python_code1 = "\
                     import wx\n\
                     f = wx.Frame(None, -1, 'Hello from wxPython!', size=(250, 150))\n\
                     f.Show()\n";
void MyFrame::OnPyFrame(wxCommandEvent& event)
{
    // For simple Python code that doesn't have to interact with the C++ code in any way, you can execute it
    // with PyRun_SimpleString. First, whenever you do anything with Python objects or code, you *MUST*
    // aquire the Global Interpreter Lock and block other Python threads from running.
    wxPyBlock_t blocked = wxPyBeginBlockThreads();
    // Execute the code in the __main__ module
    //PyRun_SimpleString(python_code1);
    PyObject* pModule = PyImport_ImportModule("showFrame");
    PyObject* pDict = PyModule_GetDict(pModule);
    PyObject* pFun = PyDict_GetItemString(pDict, "show");
    if(PyCallable_Check(pFun)){
        PyEval_CallObject(pFun, NULL);
    }

    // Finally, release the GIL and let other Python threads run.
    wxPyEndBlockThreads(blocked);
}
void MyFrame::RedirectStdio()
{
    // This is a helpful little tidbit to help debugging and such. It redirects Python's stdout and stderr to a
    // window that will popup only on demand when something is printed, like a traceback.
    char* python_redirect = "\
                            import sys\n\
                            import wx\n\
                            output = wx.PyOnDemandOutputWindow()\n\
                            sys.stdin = sys.stderr = output\n";
    wxPyBlock_t blocked = wxPyBeginBlockThreads();
    PyRun_SimpleString(python_redirect);
    wxPyEndBlockThreads(blocked);
}
char* python_code2 = "import sys\n"
    "sys.path.append('.')\n"
    "import embedded_sample\n"
    "def makeWindow(parent):\n"
    "\twin = embedded_sample.MyPanel(parent)\n"
    "\treturn win\n";
wxWindow* MyFrame::DoPythonStuff(wxWindow* parent)
{
    // More complex embedded situations will require passing C++ objects to Python and/or returning objects
    // from Python to be used in C++. This sample shows one way to do it. NOTE: The above code could just
    // have easily come from a file, or the whole thing could be in the Python module that is imported and
    // manipulated directly in this C++ code. See the Python API for more details.
    wxWindow* window = NULL;
    PyObject* result;
    // As always, first grab the GIL
    wxPyBlock_t blocked = wxPyBeginBlockThreads();
    // Now make a dictionary to serve as the global namespace when the code is executed. Put a reference to
    //the builtins module in it. (Yes, the names are supposed to be different, I don't know why...)
    PyObject* globals = PyDict_New();
    PyObject* builtins = PyImport_ImportModule("__builtin__");
    PyDict_SetItemString(globals, "__builtins__", builtins);
    Py_DECREF(builtins);
    // Execute the code to make the makeWindow function
    result = PyRun_String(python_code2, Py_file_input, globals, globals);
    // Was there an exception?
    if (! result) {
        PyErr_Print();
        wxPyEndBlockThreads(blocked);
        return NULL;
    }
    Py_DECREF(result);
    // Now there should be an object named 'makeWindow' in the dictionary that we can grab a pointer to:
    PyObject* func = PyDict_GetItemString(globals, "makeWindow");
    wxASSERT(PyCallable_Check(func));
    // Now build an argument tuple and call the Python function. Notice the use of another wxPython API to
    // take a wxWindows object and build a wxPython object that wraps it.
    PyObject* arg = wxPyMake_wxObject(parent, false);
    wxASSERT(arg != NULL);
    PyObject* tuple = PyTuple_New(1);
    PyTuple_SET_ITEM(tuple, 0, arg);
    result = PyEval_CallObject(func, tuple);
    // Was there an exception?
    if (! result)
        PyErr_Print();
    else {
        // Otherwise, get the returned window out of Python-land and into C++-ville...
        bool success = wxPyConvertSwigPtr(result, (void**)&window, _T("wxWindow"));
        wxASSERT_MSG(success, _T("Returned object was not a wxWindow!"));
        Py_DECREF(result);
    }
    // Release the python objects we still have
    Py_DECREF(globals);
    Py_DECREF(tuple);
    // Finally, after all Python stuff is done, release the GIL
    wxPyEndBlockThreads(blocked);
    return window;
}
//----------------------------------------------------------------------

嵌入在C ++中的wxPython

0 个答案: