Python / Lua Script: Detect if a modifier is pressed when running a script



  • Hello,

    How can I detect if a modifier was pressed when the user executed a script?

    Detecting a right-click would be better (i.e. execute the script on both left/right-click and detect the button).

    BTW, there seems to be a bug in Python Script: if you press Ctrl when running a script, the “File not found. Create it?” message is displayed.
    It works fine in @dail’s Lua Script.

    Thank you.

    Best regards.



  • Hi @Yaron,

    not 100% sure what you want to achieve but my regex tester script
    may give you an idea what needs to be done to capture key presses. Check Hook class.

    About the bug, where is the script stored?

    Cheers
    Claudia



  • Hello again,

    BTW, there seems to be a bug in Python Script: if you press Ctrl when running a script, the “File not found. Create it?” message is displayed.

    Correction: Ctrl+left-click opens the file instead of running the script.
    If the file name is Hebrew, it can not be found and hence the message.



  • Hello Claudia,

    Thanks for replying. I do appreciate it.

    I’d like to have a slightly different behavior in case Alt is pressed.
    I’ll have a look in your script.

    And the bug is actually a problem in handling the Hebrew file name.

    Best regards.



  • Hello Claudia,

    After a quick look in your script:
    Is using ctypes the only way to detect if a modifier was pressed?
    Can’t it be achieved with some keys module?

    And allow me to clarify:
    I want to know if a modifier was pressed when starting the script. NOT when it’s already running.

    Thanks again.
    BR



  • Hi Yaron,

    no, unfortunately neither scintilla nor notepad provide a keyup/keydown event which could be
    consumed.
    The only way, I know, is using ctypes and I think python modules which would offer this would also
    call win api to get the events.

    And allow me to clarify:
    I want to know if a modifier was pressed when starting the script. NOT when it’s already running.

    So you need to have the keyboard logger registered within startup.py ;-)

    Cheers
    Claudia



  • Hello Claudia,

    Thank you for the detailed explanation. I appreciate it.

    So you need to have the keyboard logger registered within startup.py

    I haven’t thoroughly learned the script yet.

    If I have a bool altPressed in startup.py, I’d need to set it to false on Alt-UP only after some timeout. Is that correct?

    BR



  • Yaron,
    in your case, if I understand it correctly, I would use

        if msg in [WM_KEYDOWN, WM_SYSKEYDOWN]: 
    

    to set the boolean true and

        elif msg in [WM_KEYUP,WM_SYSKEYUP]: 
    

    to set it to false

    and you need to handle the cases when alt together with other modifiers is pressed.

    Cheers
    Claudia



  • @Yaron

    Detecting a right-click would be better (i.e. execute the script on both left/right-click and detect the button).

    sorry, I missed this one.
    So you do have defined a button in the toolbar, correct?
    And when clicking with left mouse = normal run but when clicking with right mouse then advanced run?

    Cheers
    Claudia



  • If I have a bool altPressed in startup.py, I’d need to set it to false on Alt-UP only after some timeout. Is that correct?

    Or setting it to false only in the altDependentScript.
    I’ll think about it.

    You’ve been very helpful as always. :)
    Thank you very much.

    BR



  • Yaron, in case you want to get the mouse clicks see here.

    Cheers and good night
    Claudia



  • Hello again Claudia,

    Detecting a right-click would be better (i.e. execute the script on both left/right-click and detect the button).

    sorry, I missed this one.
    So you do have defined a button in the toolbar, correct?
    And when clicking with left mouse = normal run but when clicking with right mouse then advanced run?

    That’s correct.

    in case you want to get the mouse clicks see here.

    Getting the specific command/button position would be too much. :)

    Thanks again. Highly appreciated.

    Good night.



  • As far as LuaScript goes you’d probably be alot more limited as you have to use what Scintilla/Notepad++ provides which you can catch double clicks and get the modifier keys but don’t think there’s a way to distinguish between left or right click. You could also register the same function with more than one keyboard shortcut, such as “F5”, “Ctrl+F5”, “Alt+F5”, etc…but this is not ideal.

    Python gives more possibilities as far as interacting with the OS so this is probably your better option depending what you need exactly.



  • Hello @dail,

    Thank you for the additional info. I appreciate it.

    If I understand it correctly, SCN_DOUBLECLICK is only relevant to the editor.
    Double-click could have been useful, but I need it for a command or a toolbar button.

    And thanks again for the great Lua Script plugin.
    BTW, Ctrl+left-click to open the file instead of running the script could be a nice addition to Lua Script.
    What do you think?

    BR



  • but I need it for a command or a toolbar button.

    Oh! Now I see what you are doing. In this case PythonScript is your best option.

    Ctrl+left-click to open the file instead of running the script could be a nice addition to Lua Script.

    Honestly I don’t even know if would be possible. Since individual functions are registered instead of files, there is nothing that associates where a function is defined.



  • Hello @dail,

    Oh! Now I see what you are doing. In this case PythonScript is your best option.

    A simple example for what I meant:
    A script TypeLetter types a letter in the editor. Using Customize Toolbar, I’ve assigned a toolbar button to the script.
    I want it to normally type A but if Alt is down when pressing the toolbar button type B.

    Claudia’s suggestion is a good option, but I think I’d have to use some timeout.
    Using another script Toggle TypeLetter Mode is another option which should work well in Lua Script too.

    Since individual functions are registered instead of files…

    I didn’t think about that. :)

    Thanks again.
    BR



  • Hello Yaron

    a quick script about what I meant with mouse click capture.

    In one script you intercept the window proc (needs to be called first, startup.py might be good choice)

    from ctypes import windll, byref, wintypes, WINFUNCTYPE, Structure, sizeof
    
    WndProcType = WINFUNCTYPE(wintypes.LONG,
                              wintypes.HWND,
                              wintypes.UINT,
                              wintypes.WPARAM,
                              wintypes.LPARAM)
    GWL_WNDPROC = -4
    
    WNDENUMPROC = WINFUNCTYPE(wintypes.BOOL,
                              wintypes.HWND,
                              wintypes.LPARAM)
    
    
    _g = globals()
    CAPTURE_MOUSE_CLICK = _g.get('CAPTURE_MOUSE_CLICK', False)
    OLD_WND_PROC = _g.get('OLD_WND_PROC', None)
    LEFT_MOUSE_CLICK_MOD = False
    
    class Hook():
    
        def EnumCallback(self, hwnd, lparam):
            curr_class = (wintypes.WCHAR * 256)()
            windll.user32.GetClassNameW(hwnd, curr_class, 256)
            if curr_class.value.lower() == 'toolbarwindow32':
                self.toolbar_handle = hwnd
                return False
            return True
    
        def __init__(self):
            self.toolbar_handle = None
            parent = windll.user32.FindWindowA('Notepad++',None)
            windll.user32.EnumChildWindows(parent, WNDENUMPROC(self.EnumCallback), 0)
    
            self.oldWndProc = None
    
            self.SHIFT_PRESSED = False
            self.CTRL_PRESSED = False
            self.ALT_PRESSED = False
    
        def register(self):
            if self.toolbar_handle:
                self.new_wnd_proc = WndProcType(self.sciWndProc)
                windll.kernel32.SetLastError(0)
                self.oldWndProc = windll.user32.SetWindowLongA(self.toolbar_handle, GWL_WNDPROC, self.new_wnd_proc)
    
                if self.oldWndProc:
                    global OLD_WND_PROC
                    OLD_WND_PROC = self.oldWndProc
                else:
                    _err = 'GetLastError:{}'.format(windll.kernel32.GetLastError())
                    notepad.messageBox('Could not register hook:\n{}\n'.format(_err) +
                                        'Shortcuts won\'t work',
                                        'Register Hook Failure', 0)
            else:
                console.write('no toolbar_handle found')
    
        def unregister(self):
            if OLD_WND_PROC:
                self.oldWndProc = OLD_WND_PROC
                windll.kernel32.SetLastError(0)
                dummy = windll.user32.SetWindowLongA(self.toolbar_handle, GWL_WNDPROC, self.oldWndProc)
                if not dummy:
                    _err = 'GetLastError:{}'.format(windll.kernel32.GetLastError())
                    notepad.messageBox('Could not unregister hook:\n{}\n'.format(_err) +
                                        'It is recommended to save data and restart npp to prevent data loss',
                                        'Unregister Hook Failure', 0)
    
            else:
                console.write('ERROR no saved window proc found')
    
        def sciWndProc(self, hWnd, msg, wParam, lParam):
            if msg == 0x0201: # WM_LBUTTONDOWN
                global LEFT_MOUSE_CLICK_MOD
                if wParam == 5: # 0x0001 LButton + 0x0004 Shift
                    console.write('left mouse click while holding shift\n')
                    LEFT_MOUSE_CLICK_MOD = True
                else:
                    console.write('left mouse click\n')
                    LEFT_MOUSE_CLICK_MOD = False
    
            return windll.user32.CallWindowProcA (self.oldWndProc, hWnd, msg, wParam, lParam)
    
    # -----------------------------------------------------------------------------
    _hook = Hook()
    if not CAPTURE_MOUSE_CLICK:
        _hook.register()
        CAPTURE_MOUSE_CLICK = True
        console.write('registered')
    else:
        _hook.unregister()
        CAPTURE_MOUSE_CLICK = False
        console.write('unregistered')
    

    in another script something like

    import datetime
    print datetime.datetime.now()
    print 'LEFT_MOUSE_CLICK_MOD:{}'.format(LEFT_MOUSE_CLICK_MOD)
    

    The first script gets the handle of the toolbar and hooks it message queue.
    Once you click a button the global variable is set and the second script gets executed.

    Cheers
    Claudia



  • Hello Claudia,

    Sorry for the late reply. I was not by my PC.
    And thank you for the beautiful script. I appreciate your kindness.

    Now that you capture both the click and the modifier, there’s no need to use timeout and it works like a charm.

    Two follow-up questions with your permission:

    1. Customize Toolbar inserts a separator on pressing Shift and left-clicking a toolbar button.
      Which module should I import in order to use GetKeyState() and detect Alt?

    2. The little programming experience I have is from Firefox.
      In that browser adding a right-click functionality to a toolbar button is done as follows:

    • Get A specific toolbar button object.
    • Add a click listener to that button and assign your own action to right-click.

    I suppose this procedure would be more complex in NPP.

    Actually you can replace in your script

    if wParam == 5: # 0x0001 LButton + 0x0004 Shift
    

    with

    if wParam == 3: # 0x0001 LButton + 0x0002 MK_RBUTTON
    

    and then if you hold the right button down and left-click - you can execute the script in “alternative mode”.


    Another simple (and not as elegant) way to run a script in two modes:
    In startup (py or lua) add testScriptDefaultMode = True.
    Create a script Toggle TestScript Default Mode containing two lines:

    global testScriptDefaultMode 
    testScriptDefaultMode = not testScriptDefaultMode 
    

    In TestScript check if testScriptDefaultMode:.

    Assign a simple shortcut (e.g. Alt+Spacebar) to Toggle TestScript Default Mode and use it to quickly toggle the modes…


    Thanks again.
    Have a nice weekend.



  • @Yaron

    Customize Toolbar inserts a separator on pressing Shift and left-clicking a toolbar button.
    Which module should I import in order to use GetKeyState() and detect Alt?

    The function is also called GetKeyState and is in user32.dll.
    You need to provide the virtual key code to get the state, so something like

    alt_state = windll.user32.GetKeyState(0x12)
    

    but using wine, I was not able to press alt and do left click with mouse.
    Would be interesting to see if this works on Windows.

    The little programming experience I have is from Firefox.
    In that browser adding a right-click functionality to a toolbar button is done as follows:
    Get A specific toolbar button object.
    Add a click listener to that button and assign your own action to right-click.
    I suppose this procedure would be more complex in NPP.

    I think so too. Out of my mind, you would need to find notepad++ window handle,
    enumerate child windows to get toolbar, enumerate toolbar child windows to get
    the button in question (not sure how to identify), register a function which hooks into
    buttons message queue and I don’t know what happens if another program accesses toolbar
    to modify (or add/delete) a button?? I’m pretty sure it can be done but I’m not convinced
    it should be done.

    Another possible solution to run script in alternate mode would be to use a
    inputbox (prompt method) ;-) (also not as elegant but most painless version) :-D

    Cheers
    Claudia



  • Hello Claudia,

    The function is also called GetKeyState and is in user32.dll.

    Great. Thank you.

    but using wine, I was not able to press alt and do left click with mouse.
    Would be interesting to see if this works on Windows.

    alt_state = windll.user32.GetKeyState(0x12)
    if alt_state < 0:
    

    Works perfectly.

    Out of my mind, you would need to find notepad++ window handle…

    Your confirmation that this is indeed rather complex is important.

    Another possible solution to run script in alternate mode would be to use a
    inputbox

    So I have multiple choices now. :)
    Being a “mouse-oriented” user, your script detecting if the right button was down when left-clicking would probably fit me best.

    Thanks again for your time and clever ideas. I do appreciate it.
    BR


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