Hello all,

No idea whether somebody has encountered similar problem.
I am setting the windows icon(on the top-left side of the application window) with QApplication::setWindowIcon(const QIcon&)
The icon file which is used is ICO format under windows system.

before I imported QT, the Windows function i used could correctly decide which image in the .ico file should be used (under proper resolution).

Qt Code: 
  1. hAppIcon = LoadIcon(Instance(), ":icons/app.ico");
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I was expecting QIcon also do the right job, but it failed.

Qt Code: 
  1. QApplication::setWindowIcon(QIcon(QPixmap(":icons/app.ico")));
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seems that QIcon only reads the first image from app.ico and displays it on the window.
e.g. the first image from app.ico is with size 48*48 but actually for the window the one with size 16*16 should be used.

by reading the documentation of QPixmap, it doesnt support .ico format. On the other hand, there are lots of sample codes on the internet in which .ico are used in QPixmap.
It confused me so much. any ideas?