Exemple #1
0
    def test_trace(self):
        v = Variable(self.root)
        vname = str(v)
        trace = []

        def read_tracer(*args):
            trace.append(('read', ) + args)

        def write_tracer(*args):
            trace.append(('write', ) + args)

        tr1 = v.trace_add('read', read_tracer)
        tr2 = v.trace_add(['write', 'unset'], write_tracer)
        self.assertEqual(sorted(v.trace_info()), [(('read', ), tr1),
                                                  (('write', 'unset'), tr2)])
        self.assertEqual(trace, [])

        v.set('spam')
        self.assertEqual(trace, [('write', vname, '', 'write')])

        trace = []
        v.get()
        self.assertEqual(trace, [('read', vname, '', 'read')])

        trace = []
        info = sorted(v.trace_info())
        v.trace_remove('write', tr1)  # Wrong mode
        self.assertEqual(sorted(v.trace_info()), info)
        with self.assertRaises(TclError):
            v.trace_remove('read', 'spam')  # Wrong command name
        self.assertEqual(sorted(v.trace_info()), info)
        v.get()
        self.assertEqual(trace, [('read', vname, '', 'read')])

        trace = []
        v.trace_remove('read', tr1)
        self.assertEqual(v.trace_info(), [(('write', 'unset'), tr2)])
        v.get()
        self.assertEqual(trace, [])

        trace = []
        del write_tracer
        gc.collect()
        v.set('eggs')
        self.assertEqual(trace, [('write', vname, '', 'write')])

        trace = []
        del v
        gc.collect()
        self.assertEqual(trace, [('write', vname, '', 'unset')])
Exemple #2
0
    def test_trace(self):
        v = Variable(self.root)
        vname = str(v)
        trace = []
        def read_tracer(*args):
            trace.append(('read',) + args)
        def write_tracer(*args):
            trace.append(('write',) + args)
        tr1 = v.trace_add('read', read_tracer)
        tr2 = v.trace_add(['write', 'unset'], write_tracer)
        self.assertEqual(sorted(v.trace_info()), [
                         (('read',), tr1),
                         (('write', 'unset'), tr2)])
        self.assertEqual(trace, [])

        v.set('spam')
        self.assertEqual(trace, [('write', vname, '', 'write')])

        trace = []
        v.get()
        self.assertEqual(trace, [('read', vname, '', 'read')])

        trace = []
        info = sorted(v.trace_info())
        v.trace_remove('write', tr1)  # Wrong mode
        self.assertEqual(sorted(v.trace_info()), info)
        with self.assertRaises(TclError):
            v.trace_remove('read', 'spam')  # Wrong command name
        self.assertEqual(sorted(v.trace_info()), info)
        v.get()
        self.assertEqual(trace, [('read', vname, '', 'read')])

        trace = []
        v.trace_remove('read', tr1)
        self.assertEqual(v.trace_info(), [(('write', 'unset'), tr2)])
        v.get()
        self.assertEqual(trace, [])

        trace = []
        del write_tracer
        gc.collect()
        v.set('eggs')
        self.assertEqual(trace, [('write', vname, '', 'write')])

        trace = []
        del v
        gc.collect()
        self.assertEqual(trace, [('write', vname, '', 'unset')])
Exemple #3
0
def SaveVar(var: _TK.Variable, master=None, value=None, name=None, filename='data.pkl') \
        -> (_TK.Variable):
    """Save tkinter variable data in a pickle file and load the 
    same value when the program is executed next time. 

    #### If the content of the file changes, it might not load correct values \
        to the assigned variables. To avoid this issue use `name` to \
        refer to the exact assigned values later.

    ### Args:
    - `var`: Give the `tkinter.Variable` class like (`tk.StringVar`, `tk.IntVar`).
    - `master`: Parent widget.
    - `value`: Set value.
    - `name`: Set a name to group variables or to refer to assigned value when loaded.
    - `filename`: Set the name of the save file. (To make the file invisible in the \
            directory start the name of the file with "." like ".cache-savevar")

    ### Return:
    - returns the tk.Variable instance passed to `var` argument.

    ### Example:
        root = tk.Tk()
        var1 = SaveVar(tk.StringVar,'Enter Username','Var1','.cache-savevar')
        var2 = SaveVar(tk.StringVar,'Enter Password','Var2','.cache-savevar')
        tk.Entry(root,textvariable=var1).pack()
        tk.Entry(root,textvariable=var2).pack()
        root.mainloop()"""
    def update_val(*args):
        """Internal function for updating the value for variable"""
        try:  # try/except , if the file doesn't exists.
            open1 = open(filename, 'rb')
            tmpdict = pkl.load(open1)  # load saved dictionary data.
            # Block of code to check for the right value.
            if tmpdict.get(str(var)):
                old, default = tmpdict.get(str(var))
                new = var.get()
                if new != default:
                    var.set(new)
                elif new == default and not startup[0]:
                    var.set(default)
                else:
                    var.set(old)
            tmpdict.update({str(var): (var.get(), defaultval)})
            open1.close()
        except Exception as e:
            tmpdict = {}
            tmpdict[str(var)] = (var.get(), defaultval)

        open2 = open(filename, 'wb')
        pkl.dump(tmpdict, open2)
        startup[0] = False
        open2.close()

    startup = [True]
    if not(filename.endswith('.pickle') or filename.endswith('.pkl')) \
            and not filename.startswith('.'):
        filename = filename + '.pkl'
    var = var(master=master, value=value, name=name)
    defaultval = var.get()  # get a default value of the variable
    update_val()
    for mode, cbname in (var.trace_info()):
        if mode[0] == 'write' and update_val.__name__ in cbname:
            try:
                var.trace_remove('write', cbname)
            except:
                pass
    res = var.trace_add('write', update_val)
    return var