wxWidgets在编译时包含图像

Question

I've been trying to make a simple wxWidgets program with just a button with a picture on it. I've been able to make the button with the image on it easily enough, but my problem arises when including it.

So far, I've only been able to fetch the image during run-time (the image has to be in the same folder as the .exe file; otherwise, I get error 2: the system cannot find the file specified). With this method, I have no problems -- the program works just fine. What I'm trying to do, however, is to #include the file so that it is embedded during compile-time, so that it doesn't need to be available during run-time.

I've tried #including the file (both as .png and as .xpm), and I've also tried adding it to the resource includes (this is on Visual Studio 2017). Neither of these worked -- the first method still required the image to be in the same folder, and the second failed during compilation (as far as I can tell, it wasn't able to read the .xpm file).

Here is the relevant code, if it helps:

/*relevant includes*/
#include "happyFace.png" //this isn't working. the file is still needed
||
#include "happyFace.xpm" //ditto
/*I have also tried putting these lines in the resource includes.*/


/*code*/
wxInitAllImageHandlers();
wxBitmap bitmap("happyFace.xpm", wxBITMAP_TYPE_XPM); //only works in same directory at run-time
||
wxBitmap bitmap("happyFace.png", wxBITMAP_TYPE_PNG); //ditto

wxButton *button = new wxButton(this, ID_BMP_BUTTON);
button->SetBitmap(bitmap);
//the rest of the button programming and stuff

Sorry if I haven't provided enough information; I can provide more if necessary. I would really appreciate any help. Thanks!

Answer 1

Two possibilities... Number 1 is simplest. It's been a long time since I wrote the code I'm looking at, so the details are fuzzy.

1. In Visual Studio, Solution Explorer, add the image into the resource files . Assume the name of the resourse is sample.rc . Then it can be used like so to set the main icon...

    SetIcon(wxICON(sample)); 

Method 1 must be used in order for MS Windows Explorer to display the main icon. I do not remember how to use .rc resources for other things, but it should be easy to figure out.

2. I did it this way before I discovered VS resource (.rc) files. Compile the file-image into the program "by hand." In other words, write a program that will read an image file and produce bit-for-bit copy in a .cpp file. Then compile that .cpp into the program. Here I have the file-image in memory as an object named dj::main_cursor. Note that the in-memory version is a bit-for-bit copy of a .cur file.

    dj::captured_file &c1file(dj::main_cursor); wxMemoryInputStream cistr(c1file.contents, c1file.size); cursor1 = wxCursor(wxImage(cistr, wxBITMAP_TYPE_CUR)); 

   FYI, I defined the structure dj::captured_file like so:

    struct captured_file { const char *name; const unsigned long size; const void *contents; captured_file(const char*fn, size_t sz, const void*c) : name(fn) , contents(c) , size(sz) {} }; 

See also, Embedding PNG Images into Windows RC Files

I found some other documentation.

Resources and Application Icon All applications using wxMSW should have a Windows resource file (.rc extension) and this file should include include/wx/msw/wx.rc file which defines resources used by wxWidgets itself.

Among other things, wx.rc defines some standard icons, all of which have names starting with the "wx" prefix. This normally ensures that any icons defined in the application's own resource file come before them in alphabetical order which is important because Explorer (Windows shell) selects the first icon in alphabetical order to use as the application icon which is displayed when viewing its file in the file manager. So if all the icons defined in your application start with "x", "y" or "z", they won't be used by Explorer. To avoid this, ensure that the icon which is meant to be used as the main application icon has a name preceding "wxICON" in alphabetical order.

http://docs.wxwidgets.org/3.1.0/page_port.html

Answer 2

Here is how you should do it:

#include "happyFace.xpm"
wxBitmap bitmap = wxBitmap( happyFace ); // assuming the variable name is "happyFace" inside the xpm

Then you will use bitmap object just like usual. Assuming that the file happyFace.xpm is available for compilation.