screensaver/monitor turns off when calling mouse_event

Question

Good day,

    I have a code that moves the cursor in a specified x and y coordinates. When I run it, sometimes the monitor turns off but sometimes it works normally. Tested it on a different PC , instead their screen saver turns on upon running the program. Does anybody know what is wrong?

Thanks!

Answer 1

May be the screen saver is running when you have kept the system idle. More over do not use the mouse_event.This function has been superseded. Use SendInput instead. And when your program starts call the SystemParametersInfo with the SPI_SETBLOCKSENDINPUTRESETS, so that the screensaver will not be activated while your program is using the SendInput() function.

Answer 2

Thank you! So does that mean that everytime SendInput in used the screen saver will activate? I used SendInput to simulate a left click, when it triggers the screen saver also triggers.

Answer 3

lemonsito wrote:

Thank you! So does that mean that everytime SendInput in used the screen saver will activate? I used SendInput to simulate a left click, when it triggers the screen saver also triggers.

 

What will happen if you disable the screesaver and then run your program.

Answer 4

I've got the same/similar problem

 

I'm using SendInput(mouse stuff) to simulate user input for testing of a program I am working on.

 

if there is a screen saver enabled on the PC (XP,2003,Vista), then frequently the screen saver starts when I use SendInput - not after the screensaver timeout (which is 15mins) - and if power saving is enabled on the monitor, then the monitor also shuts off.

 

it is happening within seconds of me starting that function of the program.

 

I have tried adding

SystemParametersInfo(SPI_SETBLOCKSENDINPUTRESETS,FALSE,NULL,FALSE);

 but no different.

 

only current reliable workaround is to disable screen saver and monitor power saving.

Answer 5

just found the soltuon I think .....

 

http://groups.google.com.au/group/comp.os.ms-windows.programmer.win32/browse_thread/thread/f59ee6bab139413e/f3dadd558777c707?hl=en&lnk=st&q=SendInput+bug#f3dadd558777c707

 

need to zero the time member

 

Answer 6

I had exactly the same problem with my application - built with Delphi XE2 - with SendInput-function at XP, Win7 and Win8.

Now, when I use ZeroMemory-function for tagINPUT-structure before feeding mouse xy-coordinates and flags to it, screen stays on normally. So weird..as far as I know Delphi should reset the memory area used beforehand. Thanks for the link!