www.pudn.com > HIDClass.zip > MouseReader.pas

unit MouseReader; 
 
interface 
 
uses 
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 
  HidControllerClass, StdCtrls; 
 
type 
  TForm1 = class(TForm) 
    ListBox1: TListBox; 
    JvHidDeviceController1: TJvHidDeviceController; 
    Label1: TLabel; 
    Label2: TLabel; 
    Label3: TLabel; 
    Buttons: TLabel; 
    DeltaX: TLabel; 
    DeltaY: TLabel; 
    procedure JvHidDeviceController1DeviceChange(Sender: TObject); 
  private 
    { Private declarations } 
  public 
    { Public declarations } 
    DevList: TList; 
  end; 
 
  TMouseReport = packed record 
    ReportID: Byte; 
    Buttons:  Byte; 
    DeltaX:   Shortint; 
    DeltaY:   Shortint; 
    Dummy:    array [0..11] of Byte; 
  end; 
 
  TMouseThread = class(TThread) 
  private 
    Dev:      TJvHidDevice; 
    DevIndex: Integer; 
    Data:     TMouseReport; 
  public 
    procedure Execute; override; 
    procedure HandleMouseData; 
  end; 
 
var 
  Form1: TForm1; 
 
implementation 
 
{$R *.DFM} 
 
procedure TForm1.JvHidDeviceController1DeviceChange(Sender: TObject); 
var 
  I: Integer; 
  Trd: TMouseThread; 
  HidDev: TJvHidDevice; 
begin 
  // an HID device has been plugged or unplugged 
  // we kill all threads and create ne ones 
  if DevList = nil then 
    DevList := TList.Create; 
  for i := 0 to DevList.Count - 1 do 
  begin 
    Trd := DevList.Items[I]; 
    // freeing the HID device closes its file handles 
    // and the pending ReadFileEx will fail allowing 
    // the thread to terminate 
    // a pending ReadFile would not fail but wait forever 
    Trd.Dev.Free; 
    Trd.Terminate; 
  end; 
  DevList.Clear; 
  ListBox1.Clear; 
  // get all devices we are interested in 
  while JvHidDeviceController1.CheckOutByClass(HidDev, cHidMouseClass) do 
  begin 
    // start a thread for each device 
    Trd := TMouseThread.Create(True); 
    with Trd do 
    begin 
      // initialize threads data 
      FreeOnTerminate := True; 
      Dev := HidDev; 
      DevIndex := DevList.Count; 
      DevList.Add(Trd); 
      ListBox1.Items.Add(HidDev.ProductName); 
      // let the thread run 
      Resume; 
    end; 
  end; 
end; 
 
procedure TMouseThread.HandleMouseData; 
begin 
  // select the device the data comes from 
  Form1.ListBox1.ItemIndex := DevIndex; 
  // show the data read 
  Form1.Buttons.Caption := Format('%.2x',[Data.Buttons]); 
  Form1.DeltaX.Caption  := Format('%d',  [Data.DeltaX]); 
  Form1.DeltaY.Caption  := Format('%d',  [Data.DeltaY]); 
end; 
 
procedure TMouseThread.Execute; 
 
  procedure Dummy(ErrorCode: DWORD; Count: DWORD; Ovl: POverlapped); stdcall; 
  begin 
  end; 
 
begin 
  while not Terminated do 
  begin 
    // read mouse data 
    Dev.ReadFileEx(Data, Dev.Caps.InputReportByteLength, @Dummy); 
    // wait for read to complete 
    while (not Terminated) and (SleepEx(5000, True) <> WAIT_IO_COMPLETION) do 
      { nothing }; 
    // show data read 
    if not Terminated then 
      Synchronize(HandleMouseData); 
  end; 
end; 
 
end.