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copied!<p>This does what you want.</p> <p>First, you need a program that runs in the background and listens to, and responds to, keystrokes. Like this:</p> <pre><code>program Project1; uses Windows, Messages, ShellAPI; var W: HWND; M: MSG; const WM_SETHOTKEY = WM_APP + 1; WM_UNSETHOTKEY = WM_APP + 2; AppName = 'Rejbrand Hot Key Listener'; const FileNames: array[0..1] of string = ('notepad.exe', 'pbrush.exe'); begin if FindWindow('STATIC', PChar(AppName)) <> 0 then Exit; W := CreateWindow('STATIC', PChar(AppName), 0, 0, 0, 100, 100, HWND_MESSAGE, 0, HInstance, nil); while GetMessage(M, W, 0, 0) do case M.message of WM_HOTKEY: ShellExecute(0, nil, PChar(FileNames[M.wParam]), nil, nil, SW_SHOWNORMAL); WM_SETHOTKEY: RegisterHotKey(W, M.wParam, M.lParam shr 16, M.lParam and $FFFF); WM_UNSETHOTKEY: UnregisterHotKey(W, M.wParam); end; end. </code></pre> <p>(To create this program, select New/VCL Forms Application, and then remove the main form from the project. Then select Project/View Source and remove the <code>Application.Initialize</code> nonsense. The program should look like the above.)</p> <p>The above program listens to the messages <code>WM_SETHOTKEY</code> that registers a new Windows hotkey, <code>WM_UNSETHOTKEY</code> that removes a previously registered hotkey, and <code>WM_HOTKEY</code> that is sent by Windows when a registered hotkey is activated by the end-user. The first two messages are defined by me, in this application.</p> <p>To register a hotkey, send the message <code>WM_SETHOTKEY</code> to the window <code>W</code>. The <code>wParam</code> of the message should be the index (in the <code>FileNames</code> array) of the program to start. The <code>lParam</code> should be of the form $MMMMKKKK where $MMMM are the modifiers (<kbd>Ctrl</kbd>, <kbd>Alt</kbd>, <kbd>Shift</kbd>) and $KKKK the virtual-key code of the hotkey. To remove a hotkey, send a <code>WM_UNSETHOTKEY</code> message with the program index as <code>wParam</code> to <code>W</code>.</p> <h1>Sample usage</h1> <p>From <em>any</em> application, you can do (assuming that Project1.exe is running in the background)</p> <pre><code>const WM_SETHOTKEY = WM_APP + 1; WM_UNSETHOTKEY = WM_APP + 2; const MODIFIER_ALT = MOD_ALT shl 16; MODIFIER_CTRL = MOD_CONTROL shl 16; MODIFIER_SHIFT = MOD_SHIFT shl 16; procedure TForm1.RegisterHotkeys; var w: HWND; begin w := FindWindow('STATIC', 'Rejbrand Hot Key Listener'); PostMessage(w, WM_UNSETHOTKEY, 0, MODIFIER_CTRL + MODIFIER_ALT + ord('N')); PostMessage(w, WM_SETHOTKEY, 1, MODIFIER_CTRL + MODIFIER_ALT + ord('P')); end; </code></pre> <p>Now, even if you close this new program, notepad.exe and pbrush.exe will start on <kbd>Ctrl</kbd> + <kbd>Alt</kbd> + <kbd>N</kbd> and <kbd>Ctrl</kbd> + <kbd>Alt</kbd> + <kbd>P</kbd>, respectively.</p> <h1>Some more discussion</h1> <p>Notice that, when compiled, Project1.exe is only 20 kB small! This is <em>tiny</em> for an application made in Delphi!</p> <p>To unregister a previously registered hotkey, do</p> <pre><code>PostMessage(w, WM_UNSETHOTKEY, N, 0); </code></pre> <p>where N, in this example, is = 0 for notepad and = 1 for pbrush.</p> <p>To quit project1.exe, do</p> <pre><code>PostMessage(w, WM_QUIT, 0, 0); </code></pre> <p>But, of course, if you quit project1.exe, all hotkeys are unregistered by Windows.</p> <p>You might want to do</p> <pre><code>procedure TForm1.RegisterHotkeys; var w: HWND; begin w := FindWindow('STATIC', 'Rejbrand Hot Key Listener'); if w = 0 then MessageBox('Error: Rejbrand Hot Key Listener not running!'); PostMessage(w, WM_UNSETHOTKEY, 0, MODIFIER_CTRL + MODIFIER_ALT + ord('N')); PostMessage(w, WM_SETHOTKEY, 1, MODIFIER_CTRL + MODIFIER_ALT + ord('P')); end; </code></pre> <p>or even start project1.exe if you cannot find the window.</p>

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