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✎ CARVE FLESH

EDITING: WidgetRedirector.py

from tkinter import *

class WidgetRedirector:

"""Support for redirecting arbitrary widget subcommands.

Some Tk operations don't normally pass through Tkinter.  For example, if a
    character is inserted into a Text widget by pressing a key, a default Tk
    binding to the widget's 'insert' operation is activated, and the Tk library
    processes the insert without calling back into Tkinter.

Although a binding to <Key> could be made via Tkinter, what we really want
    to do is to hook the Tk 'insert' operation itself.

When a widget is instantiated, a Tcl command is created whose name is the
    same as the pathname widget._w.  This command is used to invoke the various
    widget operations, e.g. insert (for a Text widget). We are going to hook
    this command and provide a facility ('register') to intercept the widget
    operation.

In IDLE, the function being registered provides access to the top of a
    Percolator chain.  At the bottom of the chain is a call to the original
    Tk widget operation.

"""
    def __init__(self, widget):
        self._operations = {}
        self.widget = widget            # widget instance
        self.tk = tk = widget.tk        # widget's root
        w = widget._w                   # widget's (full) Tk pathname
        self.orig = w + "_orig"
        # Rename the Tcl command within Tcl:
        tk.call("rename", w, self.orig)
        # Create a new Tcl command whose name is the widget's pathname, and
        # whose action is to dispatch on the operation passed to the widget:
        tk.createcommand(w, self.dispatch)

def __repr__(self):
        return "WidgetRedirector(%s<%s>)" % (self.widget.__class__.__name__,
                                             self.widget._w)

def close(self):
        for operation in list(self._operations):
            self.unregister(operation)
        widget = self.widget; del self.widget
        orig = self.orig; del self.orig
        tk = widget.tk
        w = widget._w
        tk.deletecommand(w)
        # restore the original widget Tcl command:
        tk.call("rename", orig, w)

def register(self, operation, function):
        self._operations[operation] = function
        setattr(self.widget, operation, function)
        return OriginalCommand(self, operation)

def unregister(self, operation):
        if operation in self._operations:
            function = self._operations[operation]
            del self._operations[operation]
            if hasattr(self.widget, operation):
                delattr(self.widget, operation)
            return function
        else:
            return None

def dispatch(self, operation, *args):
        '''Callback from Tcl which runs when the widget is referenced.

If an operation has been registered in self._operations, apply the
        associated function to the args passed into Tcl. Otherwise, pass the
        operation through to Tk via the original Tcl function.

Note that if a registered function is called, the operation is not
        passed through to Tk.  Apply the function returned by self.register()
        to *args to accomplish that.  For an example, see ColorDelegator.py.

'''
        m = self._operations.get(operation)
        try:
            if m:
                return m(*args)
            else:
                return self.tk.call((self.orig, operation) + args)
        except TclError:
            return ""

class OriginalCommand:

def __init__(self, redir, operation):
        self.redir = redir
        self.operation = operation
        self.tk = redir.tk
        self.orig = redir.orig
        self.tk_call = self.tk.call
        self.orig_and_operation = (self.orig, self.operation)

def __repr__(self):
        return "OriginalCommand(%r, %r)" % (self.redir, self.operation)

def __call__(self, *args):
        return self.tk_call(self.orig_and_operation + args)

def main():
    root = Tk()
    root.wm_protocol("WM_DELETE_WINDOW", root.quit)
    text = Text()
    text.pack()
    text.focus_set()
    redir = WidgetRedirector(text)
    global previous_tcl_fcn
    def my_insert(*args):
        print("insert", args)
        previous_tcl_fcn(*args)
    previous_tcl_fcn = redir.register("insert", my_insert)
    root.mainloop()
    redir.unregister("insert")  # runs after first 'close window'
    redir.close()
    root.mainloop()
    root.destroy()

if __name__ == "__main__":
    main()

CANCEL

Name	Type	Size	Modified	Actions
↩ ..	DIR	—	—
📁 __pycache__/	DIR	—	2025-02-17 05:50
📁 Icons/	DIR	—	2025-02-17 05:50
📁 idle_test/	DIR	—	2025-02-17 05:50
📄 __init__.py	PY	37 B	2024-04-17 16:58	EDIT
📄 __main__.py	PY	109 B	2024-04-17 16:58	EDIT
📄 aboutDialog.py	PY	6.4 KB	2024-04-17 16:58	EDIT
📄 AutoComplete.py	PY	8.9 KB	2024-04-17 16:58	EDIT
📄 AutoCompleteWindow.py	PY	17.3 KB	2024-04-17 16:58	EDIT
📄 AutoExpand.py	PY	2.4 KB	2024-04-17 16:58	EDIT
📄 Bindings.py	PY	3.4 KB	2024-04-17 16:58	EDIT
📄 CallTips.py	PY	5.8 KB	2024-04-17 16:58	EDIT
📄 CallTipWindow.py	PY	5.8 KB	2024-04-17 16:58	EDIT
📄 ChangeLog	?	55.1 KB	2017-09-19 07:32	EDIT
📄 ClassBrowser.py	PY	6.2 KB	2024-04-17 16:58	EDIT
📄 CodeContext.py	PY	8.2 KB	2024-04-17 16:58	EDIT
📄 ColorDelegator.py	PY	10.2 KB	2024-04-17 16:58	EDIT
📄 config-extensions.def	DEF	2.7 KB	2017-09-19 07:32	EDIT
📄 config-highlight.def	DEF	1.7 KB	2017-09-19 07:32	EDIT
📄 config-keys.def	DEF	7.3 KB	2017-09-19 07:32	EDIT
📄 config-main.def	DEF	2.5 KB	2017-09-19 07:32	EDIT
📄 configDialog.py	PY	51.6 KB	2024-04-17 16:58	EDIT
📄 configHandler.py	PY	28.6 KB	2024-04-17 16:58	EDIT
📄 configHelpSourceEdit.py	PY	6.6 KB	2024-04-17 16:58	EDIT
📄 configSectionNameDialog.py	PY	4.2 KB	2024-04-17 16:58	EDIT
📄 CREDITS.txt	TXT	1.8 KB	2017-09-19 07:32	EDIT
📄 Debugger.py	PY	16 KB	2024-04-17 16:58	EDIT
📄 Delegator.py	PY	665 B	2024-04-17 16:58	EDIT
📄 dynOptionMenuWidget.py	PY	1.3 KB	2024-04-17 16:58	EDIT
📄 EditorWindow.py	PY	64.8 KB	2024-04-17 16:58	EDIT
📄 extend.txt	TXT	3.6 KB	2017-09-19 07:32	EDIT
📄 FileList.py	PY	3.7 KB	2024-04-17 16:58	EDIT
📄 FormatParagraph.py	PY	7 KB	2024-04-17 16:58	EDIT
📄 GrepDialog.py	PY	4 KB	2024-04-17 16:58	EDIT
📄 help.txt	TXT	11.7 KB	2017-09-19 07:32	EDIT
📄 HISTORY.txt	TXT	10.1 KB	2017-09-19 07:32	EDIT
📄 HyperParser.py	PY	10.3 KB	2024-04-17 16:58	EDIT
📄 idle.py	PY	400 B	2024-04-17 16:58	EDIT
📄 idle.pyw	PYW	671 B	2017-09-19 07:32	EDIT
📄 IdleHistory.py	PY	4 KB	2024-04-17 16:58	EDIT
📄 idlever.py	PY	23 B	2024-04-17 16:58	EDIT
📄 IOBinding.py	PY	19.4 KB	2024-04-17 16:58	EDIT
📄 keybindingDialog.py	PY	12.1 KB	2024-04-17 16:58	EDIT
📄 macosxSupport.py	PY	7 KB	2024-04-17 16:58	EDIT
📄 MultiCall.py	PY	17.1 KB	2024-04-17 16:58	EDIT
📄 MultiStatusBar.py	PY	783 B	2024-04-17 16:58	EDIT
📄 NEWS.txt	TXT	33.6 KB	2017-09-19 07:32	EDIT
📄 ObjectBrowser.py	PY	3.7 KB	2024-04-17 16:58	EDIT
📄 OutputWindow.py	PY	4.3 KB	2024-04-17 16:58	EDIT
📄 ParenMatch.py	PY	6.5 KB	2024-04-17 16:58	EDIT
📄 PathBrowser.py	PY	2.8 KB	2024-04-17 16:58	EDIT
📄 Percolator.py	PY	2.6 KB	2024-04-17 16:58	EDIT
📄 PyParse.py	PY	19 KB	2024-04-17 16:58	EDIT
📄 PyShell.py	PY	56.5 KB	2024-04-17 16:58	EDIT
📄 README.txt	TXT	2.4 KB	2017-09-19 07:32	EDIT
📄 RemoteDebugger.py	PY	11.7 KB	2024-04-17 16:58	EDIT
📄 RemoteObjectBrowser.py	PY	964 B	2024-04-17 16:58	EDIT
📄 ReplaceDialog.py	PY	5.7 KB	2024-04-17 16:58	EDIT
📄 rpc.py	PY	20.5 KB	2024-04-17 16:58	EDIT
📄 RstripExtension.py	PY	1 KB	2024-04-17 16:58	EDIT
📄 run.py	PY	13.4 KB	2024-04-17 16:58	EDIT
📄 ScriptBinding.py	PY	7.9 KB	2024-04-17 16:58	EDIT
📄 ScrolledList.py	PY	3.9 KB	2024-04-17 16:58	EDIT
📄 SearchDialog.py	PY	2 KB	2024-04-17 16:58	EDIT
📄 SearchDialogBase.py	PY	5.1 KB	2024-04-17 16:58	EDIT
📄 SearchEngine.py	PY	7.4 KB	2024-04-17 16:58	EDIT
📄 StackViewer.py	PY	3.5 KB	2024-04-17 16:58	EDIT
📄 tabbedpages.py	PY	17.7 KB	2024-04-17 16:58	EDIT
📄 textView.py	PY	3.5 KB	2024-04-17 16:58	EDIT
📄 TODO.txt	TXT	8.3 KB	2017-09-19 07:32	EDIT
📄 ToolTip.py	PY	2.7 KB	2024-04-17 16:58	EDIT
📄 TreeWidget.py	PY	14.9 KB	2024-04-17 16:58	EDIT
📄 UndoDelegator.py	PY	10.1 KB	2024-04-17 16:58	EDIT
📄 WidgetRedirector.py	PY	4.4 KB	2024-04-17 16:58	EDIT
📄 WindowList.py	PY	2.4 KB	2024-04-17 16:58	EDIT
📄 ZoomHeight.py	PY	1.3 KB	2024-04-17 16:58	EDIT