Build openssl with mingw to support Windows XP
Using pre-built openssl such as this one always causes trouble. They may require vc runtime dll like msvcr120.dll that is not available on deployed machine, or they are not compatible […]
How to check if an .exe/.dll is 32 bit or 64 bit?
Open the file with a text editor such as notepad++, the occurrence of “PE L” in the first several lines indicates it is 32 bit, while “PE d†” indicates 64 […]
qt imageformats folder
Many qt image related classes allow you to load an image from a file such as: QIcon ButtonIcon(“myprogrammingnotes.com.ico”); button->setIcon(ButtonIcon); Or, QPixmap pixmap(“myprogrammingnotes.com.ico”); QIcon ButtonIcon(pixmap); button->setIcon(ButtonIcon); That is very convenient. But […]
How to add app icon in Qt?
If you do not set an icon for your qt project, the built exe has a default icon, which seems a blank window. If you run the program, the icon […]
The FORMATETC structure of print screen clipboard
On windows, when you press the print-screen key, the screenshot is saved into system clipboard in 3 formats:CF_BITMAP, CF_DIB, and CF_DIBV5. The FORMATETC structure for these formats are: {2,1,-1,0,16}, {8,1,-1,0,5}, […]
build qt with ssl support
If you does not provide any parameter when configuring qt, the qt binaries you build will not support ssl. When you build a project that needs ssl, you will get […]
make install after building qt
After building qt from source, you may want to install the build results by running “mingw32-make install”. But wait a minute, you do not really need to install the generated […]
Difference between qmake CONFIG and qtConfig
qmake variable CONFIG contains the conditions that are evaluated to true. CONFIG += abcdefg abcdefg:xxxxxqtConfig is a qmake test function which returns true if the tested feature is an enabled […]
qmake module dependency – $$sort_depends and $$resolve_depends
There exists dependency relationship between qt modules. Some modules can only be built after some other modules are built. This is not only because some modules use the libs/header files […]
gcc error output format
When compiling, gcc may output many error messages which are dazzling. Although you can locate the error in the source code in the end, you may never notice the details […]