Get system brightness event in windows - c++

Question

Can somebody will guide me how to get brightness changes event using vc++ in windows system?
or I need to get brightness slider value whenever it will change.
Any help will be very appreciated.
Thanks in advance.

Answer 1

A late answer but since I have been looking for the same thing. Although it is true that controlling brightness is not a Windows task but sometimes a driver's task and could also be related directly to ACPI calls, we can still get some information from Windows about its changes by implementing WMI Events. In particular, you will need to implement WmiMonitorBrightnessEvent which will give you the information you need whenever Windows receives an event of brightness change. The sample code below is a direct conversion to C++/CLI of the C# code in #RRUZ answer here where he made use of WmiMonitorBrightnessEvent.
EventWatcherAsync.h
#pragma once
using namespace System;
using namespace System::Management;
ref class EventWatcherAsync
{
public:
void WmiEventHandler(Object^ sender, EventArrivedEventArgs^ e);
EventWatcherAsync();
};
EventWatcherAsync.cpp
#include "stdafx.h"
#include "EventWatcherAsync.h"
void EventWatcherAsync::WmiEventHandler(Object^ sender, EventArrivedEventArgs^ e)
{
Console::WriteLine("Active : " + e->NewEvent->Properties["Active"]->Value->ToString());
Console::WriteLine("Brightness : " + e->NewEvent->Properties["Brightness"]->Value->ToString());
Console::WriteLine("InstanceName : " + e->NewEvent->Properties["InstanceName"]->Value->ToString());
}
EventWatcherAsync::EventWatcherAsync()
{
try
{
System::String^ ComputerName = "localhost";
System::String^ WmiQuery;
ManagementEventWatcher^ Watcher;
ManagementScope^ Scope;
if (ComputerName != "localhost")
{
ConnectionOptions^ Conn = gcnew ConnectionOptions();
Conn->Username = "";
Conn->Password = "";
Conn->Authority = "ntlmdomain:DOMAIN";
Scope = gcnew ManagementScope(String::Format("\\\\{0}\\root\\WMI", ComputerName), Conn);
}
else
Scope = gcnew ManagementScope(String::Format("\\\\{0}\\root\\WMI", ComputerName));
Scope->Connect();
WmiQuery = "Select * From WmiMonitorBrightnessEvent";
Watcher = gcnew ManagementEventWatcher(Scope, gcnew EventQuery(WmiQuery));
Watcher->EventArrived += gcnew EventArrivedEventHandler(this, &EventWatcherAsync::WmiEventHandler);
Watcher->Start();
Console::Read();
Watcher->Stop();
}
catch (Exception^ e)
{
Console::WriteLine("Exception {0} Trace {1}", e->Message, e->StackTrace);
}
}
Main.cpp
#include "stdafx.h"
#include "EventWatcherAsync.h"
using namespace System;
int main(array<System::String ^> ^args)
{
Console::WriteLine("Listening {0}", "WmiMonitorBrightnessEvent");
Console::WriteLine("Press Enter to exit");
EventWatcherAsync^ eventWatcher = gcnew EventWatcherAsync();
Console::Read();
return 0;
}