Color Picker is a simple
application that
retrieves the
color codes
from any area of
your
desktop
(including any running
applications). The program
can copy that code - by
pressing the SPACE key - to
clipboard either in Hex
(0x...) or in HTML
compatible
color code
(#...). The
color is shown
even if the program has lost
focus, but you can't copy
the value to clipboard. You
can choose if you want the
application's window to be
modal (stay on top) or not.
Initially I make the window
modal. In
OnInitDialog
:
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SetWindowPos(&wndTopMost,0,0,0,0,SWP_SHOWWINDOW|SWP_NOSIZE|SWP_NOMOVE);
I use a timer to refresh the
color code of the
current pixel pointed by the
mouse pointer.
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SetTimer(m_nTimer,10,NULL);
To
retrieve the
color code of any
pixel on the
screen we must
get the device context of
the entire
screen. We can
make that with:
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HDC hDC;
hDC = CreateDC("DISPLAY",0,0,0);
The
CreateDC
function creates a device
context (DC) for a device by
using it's name. After we
take the handle to the
device context of the entire
display, we can get the
position of the cursor.
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CPoint point;
GetCursorPos(&point);
And finally we can
get
the
color code of
that point!
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COLORREF color;
color = GetPixel(hDC,point.x,point.y);
After that we can release
the device context:
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DeleteDC(hDC);
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C++/ MFC Products
