Extended Mouse Hook Demo by KodeZwerg
lazarus / 67-Windows

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KodeZwerg · 2022-12-14 00:24

Since I have corrected an example from here and showed in this thread,
what just covered the left mouse button up event, here is a full
example to discuss or freely use.

I hope you like it and it is understandable.
Full Demo Project in attachment, just source I show you here.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i unit
Unit1; (*Getting Pixel coordinate and color under mouse cursor routine
plus mousehook, rewritten by KodeZwerg used Resources for
hookhttps://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-
winuser-msllhookstructhttps://learn.microsoft.com/en-us/previous-versi
ons/windows/desktop/legacy/ms644986(v=vs.85)https://learn.microsoft.co
m/en-us/windows/win32/api/winuser/nf-winuser-
setwindowshookexwhttps://learn.microsoft.com/en-
us/windows/win32/api/winuser/nf-winuser-
callnexthookexhttps://learn.microsoft.com/en-
us/windows/win32/api/winuser/nf-winuser-unhookwindowshookexused
Resources for GetPixelhttps://learn.microsoft.com/en-
us/windows/win32/api/wingdi/nf-wingdi-
createdcwhttps://learn.microsoft.com/en-
us/windows/win32/api/wingdi/nf-wingdi-
getpixelhttps://learn.microsoft.com/en-us/windows/win32/api/wingdi/nf-
wingdi-deletedc*)  {$mode objfpc}{$H+} interface uses  Windows, //
hooks with windows api  Classes, SysUtils, Forms, Controls, Graphics,
Dialogs, StdCtrls; type   { TForm1 }   TForm1 = class(TForm)   
Label1: TLabel;    Label2: TLabel;    Label3: TLabel;    Label4:
TLabel;    Label5: TLabel;    Label6: TLabel;    procedure
FormCreate(Sender: TObject);    procedure FormDestroy(Sender:
TObject);  strict private  private  public  end; type  // structure
for pixel information  TMyPixel = packed record    R, G, B : Byte;   
X, Y    : LongInt;    Color   : TColor;  end;  // structure for low
level mouse events  TMSLLHOOKSTRUCT = record    pt          : TPoint; 
  mouseData   : DWORD;    flags       : DWORD;    time        :
DWORD;    dwExtraInfo : ULONG_PTR;  end;  PMSLLHOOKSTRUCT =
^TMSLLHOOKSTRUCT; // mouse hook message handlerfunction
LowLevelMouseProc(nCode: LongInt; wParam: WPARAM; lParam: LPARAM):
LRESULT; StdCall;// get pixel informationsfunction MyGetPixel(const X,
Y: LongInt; var MyPixel: TMyPixel): Boolean; var  Form1: TForm1; 
mHook: HHOOK; // the hook, if 0 or -1 then its
garbage implementation {$R *.lfm} function LowLevelMouseProc(nCode:
LongInt; wParam: WPARAM; lParam: LPARAM): LRESULT; StdCall;var  msLL:
PMSLLHOOKSTRUCT absolute lParam;  Pixel : TMyPixel;begin  if ((mHook =
0) or (mHook = INVALID_HANDLE_VALUE)) then    Exit(0);  Result :=
CallNextHookEx(mHook, nCode, wParam, lParam);  with msLL^ do    begin 
    // react on mouse messages      case wParam of        WM_MOUSEMOVE
    : if MyGetPixel(pt.X, pt.Y, Pixel) then                          
 begin                               Form1.Label1.Caption :=
Format('X: %d - Y: %d', [Pixel.X, Pixel.Y]);                         
    Form1.Label2.Caption := Format('R: %d - G: %d - B: %d - Color:
%d', [Pixel.R, Pixel.G, Pixel.B, Pixel.Color]);                      
     end;        WM_LBUTTONDOWN   : Form1.Label6.Caption :=
'WM_LBUTTONDOWN pressed';        WM_LBUTTONUP     : begin            
               if MyGetPixel(pt.X, pt.Y, Pixel) then                 
            begin                                 Form1.Label3.Caption
:= Format('X: %d - Y: %d', [Pixel.X, Pixel.Y]);                      
         Form1.Label4.Caption := Format('R: %d - G: %d - B: %d -
Color: %d', [Pixel.R, Pixel.G, Pixel.B, Pixel.Color]);               
              end;                             Form1.Label6.Caption :=
'WM_LBUTTONUP pressed';                           end;       
WM_MBUTTONDOWN   : Form1.Label6.Caption := 'WM_MBUTTONDOWN pressed'; 
     WM_MBUTTONUP     : Form1.Label6.Caption := 'WM_MBUTTONUP
pressed';        WM_RBUTTONDOWN   : Form1.Label6.Caption :=
'WM_RBUTTONDOWN pressed';        WM_RBUTTONUP     :
Form1.Label6.Caption := 'WM_RBUTTONUP pressed';        WM_MOUSEWHEEL 
 : if (SmallInt(HiWord(mouseData)) >= 0) then // positive = away from
user, negativ = toward to user                           
 Form1.Label6.Caption := 'WM_MOUSEWHEEL (up) triggered'              
             else                             Form1.Label6.Caption :=
'WM_MOUSEWHEEL (down) triggered';        WM_XBUTTONDOWN   : if
(HiWord(mouseData) = 1) then // 1 = xbutton1, 2 = xbutton2           
                Form1.Label6.Caption := 'WM_XBUTTONDOWN (down)
pressed'                             else                           
 Form1.Label6.Caption := 'WM_XBUTTONDOWN (up) pressed';       
WM_XBUTTONUP     : if (HiWord(mouseData) = 1) then // 1 = xbutton1, 2
= xbutton2                             Form1.Label6.Caption :=
'WM_XBUTTONUP (down) pressed'                             else       
                    Form1.Label6.Caption := 'WM_XBUTTONUP (up)
pressed';        else          Form1.Label6.Caption := 'Unknown mouse
event! (' + IntToStr(wParam) + ')'; // here you can identify more
stuff      end;    end;end; function MyGetPixel(const X, Y: LongInt;
var MyPixel: TMyPixel): Boolean;var  DC : HDC;begin  DC            :=
Windows.CreateDCW(PWideChar('DISPLAY'), nil, nil, nil);  if ((DC = 0)
or (DC = INVALID_HANDLE_VALUE)) then    Exit(False);  MyPixel.X     :=
X;  MyPixel.Y     := Y;  MyPixel.Color := Windows.GetPixel(DC, X, Y); 
MyPixel.R     := MyPixel.Color and $000000FF;  MyPixel.G     :=
(MyPixel.Color shr 8) and $000000FF;  MyPixel.B     := (MyPixel.Color
shr 16) and $000000FF;  Result        := Windows.DeleteDC(DC);end; {
TForm1 } procedure TForm1.FormCreate(Sender: TObject);const 
LWH_MOUSE_LL = LongInt(14); // 14 = low level mouse messagesbegin  //
setup hook  mHook := SetWindowsHookExW(LWH_MOUSE_LL,
@LowLevelMouseProc, hInstance, 0);  if ((mHook = 0) or (mHook =
INVALID_HANDLE_VALUE)) then    ShowMessage('Problem during Hook
install!' + sLineBreak +                'Error: ' +
SysErrorMessage(GetLastError));end; procedure
TForm1.FormDestroy(Sender: TObject);begin  // release hook  if ((mHook
<> 0) and (mHook <> INVALID_HANDLE_VALUE)) then    if (not
UnhookWindowsHookEx(mHook)) then      ShowMessage('Problem during Hook
uninstall!' + sLineBreak +                  'Error: ' +
SysErrorMessage(GetLastError));end; end.
Enjoy!

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KodeZwerg · 2022-12-14 09:05

Small update:

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i        
WM_XBUTTONDOWN   : case HiWord(mouseData) of                         
  1: Form1.Label6.Caption := 'WM_XBUTTONDOWN (down) pressed';        
                   2: Form1.Label6.Caption := 'WM_XBUTTONDOWN (up)
pressed';                             else                           
  Form1.Label6.Caption := 'WM_XBUTTONDOWN (' +
IntToStr(HiWord(mouseData)) + ') pressed';                         
 end;        WM_XBUTTONUP     : case HiWord(mouseData) of            
               1: Form1.Label6.Caption := 'WM_XBUTTONUP (down)
pressed';                             2: Form1.Label6.Caption :=
'WM_XBUTTONUP (up) pressed';                             else        
                     Form1.Label6.Caption := 'WM_XBUTTONUP (' +
IntToStr(HiWord(mouseData)) + ') pressed';                         
 end;

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fabiopesaju · 2022-12-14 13:31

this works on linux?

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Handoko · 2022-12-14 13:33

No. It has Windows in the uses clause. See the code in the first post,
line #24.

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KodeZwerg · 2022-12-14 14:21

Quote from: fabiopesaju on December 14, 2022, 02:31:41 pmthis works on
linux?Maybe compiling for Windows OS and running on Linux Wine will
work, total untested.

Quote from: Handoko on December 14, 2022, 02:33:59 pmNo. It has
Windows in the uses clause. See the code in the first post, line #24.I
also was thinking that my first lines speak for themself, I am
referring to Microsoft Windows Api pages 

If someone has code for other OS, please feel free to add your project
in here

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winni · 2022-12-14 15:56

Hi!

This is the simple way that works with all OS:

* Get the screen coordinates:  MyPoint := Mouse.CursorPos
* take a screenshot and load it into a TBitmap
* Get the color from MyBitmap.canvas.pixels[x,y]
* free the bitmap

Done

Winni

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KodeZwerg · 2022-12-15 00:48

Quote from: winni on December 14, 2022, 04:56:29 pmHi!

This is the simple way that works with all OS:
Hello Winni!
I am excited to see a simple "how" 
Quote from: winni on December 14, 2022, 04:56:29 pm* Get the screen
coordinates:  MyPoint := Mouse.CursorPos
Ugh... before I "get" a screen coordinate I need an Event, like "left
mouse button was clicked inside/outside of my app"
Where is the "simple way" that works with all OS please?
Quote from: winni on December 14, 2022, 04:56:29 pm* take a screenshot
and load it into a TBitmap
* Get the color from MyBitmap.canvas.pixels[x,y]
* free the bitmap

Done

Winni
Thanks for sharing your wisdom but it covers 0% about my threads topic
"Extended Mouse Hook" 

Please update your suggestion with an easy on all OS detecting mouse
events code