Let’s write a module which will start WinAMP when system is idle and stop it when system is in use.
Steps:
1. Use Empty module from SDK.
2. Fill out data for function GetModuleInfo:
- Code: Select all
// Module information
function GetModuleInfo(Language: String):TModuleInfo;stdcall;
var
Buffer:array [byte] of char;
begin
with Result do begin
if GetModuleFileName(hInstance,@Buffer,SizeOf(Buffer)-1)>0 then
begin
// Путь к модулю
FileName:=ExtractFileName(StrPas(Buffer));
Path:=ExtractFilePath(StrPas(Buffer));
Name:='WinAMP';
Description:='This module play music while computer idle';
Data:='02.02.2008';
Author:='Nikolai Kurkov';
AuthorEmail:='nikkurkov@gmail.com';
end;
end;
end;
3. Before launch, information about where WinAMP is installed needs to be collected, let’s do that:
- Code: Select all
Uses Registry;
Var WinAMPPath: String; PlayList: String; Process, Thread: Cardinal;
// Initialization
procedure Initialize;stdcall;
var
Reg: TRegistry;
begin
Reg:=TRegistry.Create;
Reg.RootKey:=HKEY_LOCAL_MACHINE;
if Reg.OpenKeyReadOnly('\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Winamp_is1') then
WinAMPPath:=Reg.ReadString('Inno Setup: App Path')
else
WinAMPPath:='';
end;
4. In order for module to work WinAMP is required, right? Let’s check:
- Code: Select all
// Compatible test
function Compatible: Boolean;stdcall;
begin
Result:=FileExists(WinAMPPath+'\winamp.exe');
end;
5. Now, settings window, where playlist is selected, needs to be created:
- Code: Select all
// Show module settings
procedure Settings;stdcall;
begin
// Create new form
SettingsForm := TSettingsForm.Create(Application);
SettingsForm.OpenDialog1.FileName:=PlayList;
SettingsForm.Edit1.Text:=PlayList;
// Show form
SettingsForm.ShowModal;
// If "Ok" choosen in settings window
if SettingsForm.ModalResult= mrOk then
begin
PlayList:=SettingsForm.OpenDialog1.FileName;
// Save settings
{Save action}
end;
SettingsForm.Free;
end;
6. After that, write the main function: launch.
a) I create procedure to run executable file like winamp.exe:
- Code: Select all
// Run procedure
procedure Startz;
const
ReadBuffer = 2400;
var
Security: TSecurityAttributes;
start: TStartUpInfo;
ProcessInfo: TProcessInformation;
ExitCode: Cardinal;
begin
with Security do
begin
nlength := SizeOf(TSecurityAttributes);
binherithandle := true;
lpsecuritydescriptor := nil;
end;
FillChar(Start, Sizeof(Start), #0);
start.cb := SizeOf(start);
start.dwFlags := STARTF_USESTDHANDLES +
STARTF_USESHOWWINDOW;
start.wShowWindow := SW_HIDE;
// Create process
if CreateProcess(nil, PChar(WinAMPPath+'\winamp.exe '+Playlist),
@Security,
@Security,
true,
NORMAL_PRIORITY_CLASS,
nil,
nil,
start,
ProcessInfo) then
begin
with ProcessInfo do
begin
Process:=ProcessInfo.hProcess;
Thread:=ProcessInfo.hThread;
WaitForInputIdle(Process, INFINITE); // waiting for close
WaitforSingleObject(ProcessInfo.hProcess, INFINITE);
GetExitCodeProcess(ProcessInfo.hProcess, ExitCode);
CloseHandle(Thread);
CloseHandle(Process);
end;
end;
end;
b) Then just call this procedure to run Winamp with parameters:
- Code: Select all
// Start module
function StartPlugin: Boolean;stdcall;
begin
Startz;
end;
7. Stop and pause functions are also required, they will be identical:
- Code: Select all
// Stop plugin
function StopPlugin: Boolean;stdcall;
begin
TerminateProcess(Process, 0);
end;
// Pause plugin
function PausePlugin:Boolean;stdcall;
begin
TerminateProcess(Process, 0);
end;
8. Module is ready! Now add icons (winamp.bmp (16x16) and winamp -icon64.png (64x64). It can be compiled and ready to use.
I also attached original code for Delphi for this example to this article.
See also:
Program for testing modules
Empty module
