Window capture using WM_PRINT and Python

[arN]

Hi !

I'm a Java developper and I wish to make a capture of an offscreen
window (on WinXP). It's not possible in Java, so I use a python script
and WM_PRINT, but it doesn't seem to work.

Could someone have a look at my script and give me any advise ?

TIA

--
Arnaud
my python script : python snap.py GraphicalContext_handle image_handle
--------------------------------------------------------------------------------------------------
snap.py :
"
import win32api, win32con, sys

win32api.SendMessage(sys.argv[2], win32con.WM_PAINT, sys.argv[3], 0)
win32api.SendMessage(sys.argv[2], win32con.WM_PRINT, sys.argv[3],
win32con.PRF_CHILDREN | win32con.PRF_CLIENT | win32con.PRF_OWNED)
"

------------------------------------------------------------------------------------------------
snippet from Snapshot.java :
"
public static Image snapshot(Composite bean) {
GC gc = new GC(bean);
final Image image = new Image (null, bean.getBounds().width,
bean.getBounds().height);
String commmand = "python snap.py " + gc.handle + " " + image.handle;

Runtime rt = Runtime.getRuntime();
try {
Process p = rt.exec(command);
} catch (.....)

gc.dispose();
return image;
}
"

 

[Roger Upole]

Do you get any kind of traceback when you start a process that way?
There's not much info to go on.

Sys.argv parameters are passed as strings. You'll need to do an int() on
them
before you can use them as handles. Also, not all handles are portable
between processes. Your device context handle might not be valid
even if you make it an int.

hth
Roger

Hi !

I'm a Java developper and I wish to make a capture of an offscreen window
(on WinXP). It's not possible in Java, so I use a python script and
WM_PRINT, but it doesn't seem to work.

Could someone have a look at my script and give me any advise ?

TIA

--
Arnaud
my python script : python snap.py GraphicalContext_handle image_handle
--------------------------------------------------------------------------------------------------
snap.py :
"
import win32api, win32con, sys

win32api.SendMessage(sys.argv[2], win32con.WM_PAINT, sys.argv[3], 0)
win32api.SendMessage(sys.argv[2], win32con.WM_PRINT, sys.argv[3],
win32con.PRF_CHILDREN | win32con.PRF_CLIENT | win32con.PRF_OWNED)
"

------------------------------------------------------------------------------------------------
snippet from Snapshot.java :
"
public static Image snapshot(Composite bean) {
GC gc = new GC(bean);
final Image image = new Image (null, bean.getBounds().width,
bean.getBounds().height);
String commmand = "python snap.py " + gc.handle + " " + image.handle;

Runtime rt = Runtime.getRuntime();
try {
Process p = rt.exec(command);
} catch (.....)

gc.dispose();
return image;
}
"