在python 2.7中,每次Tkinter Text小部件中发生更改时,我都试图获取回调。
程序基于此处的代码使用多个帧:Switch between two frames in tkinter
回调部分取自以下示例:http://code.activestate.com/recipes/464635-call-a-callback-when-a-tkintertext-is-modified/
两种代码都可以单独很好地工作,但是将这两种代码结合起来对我来说很难。这是我尝试使用尽可能简单的代码。
import Tkinter as tk
class Texter(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
container = tk.Frame(self)
container.pack()
self.frames = {}
for F in (ConnectPage, EditorPage):
frame = F(container, self)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky="nsew")
page_name = EditorPage.__name__
self.frames[page_name] = frame
self.show_frame(ConnectPage)
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
def get_page(self, page_name):
return self.frames[page_name]
class ConnectPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
button1 = tk.Button(self, text="SecondPage",
command=lambda: controller.show_frame(EditorPage))
button1.grid(row=2, column=3, padx=15)
class EditorPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.text = tk.Text(self, height=25, width=80)
self.text.grid(column=0, row=0, sticky="nw")
button2 = tk.Button(self, text="FirstPage",
command=lambda: controller.show_frame(ConnectPage))
button2.grid(row=2, column=3, padx=15)
self.clearModifiedFlag()
self.bind_all('<<Modified>>', self._beenModified)
def _beenModified(self, event=None):
if self._resetting_modified_flag: return
self.clearModifiedFlag()
print("Hello!")
#self.beenModified(event)
def clearModifiedFlag(self):
self._resetting_modified_flag = True
try:
self.tk.call(self._w, 'edit', 'modified', 0)
finally:
self._resetting_modified_flag = False
if __name__ == '__main__':
gui = Texter()
gui.mainloop()
我尝试仅从回调示例中提取必要的部分。修改文本后,代码会执行回调(如果self.tk.call(self._w,'edit','modified',0)行被注释掉),但不会重置已修改标志有效,因此仅注册第一个修改。
目前,我收到以下错误:第67行,在clearModifiedFlag中self.tk.call(self._w,'edit','modified',0)_tkinter.TclError:错误的选项“ edit”:必须是cget或configure
在回调示例代码中,“ edit”工作正常。
编辑:这是工作代码
import Tkinter as tk
class Texter(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
container = tk.Frame(self)
container.pack()
self.frames = {}
for F in (ConnectPage, EditorPage):
frame = F(container, self)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky="nsew")
page_name = EditorPage.__name__
self.frames[page_name] = frame
self.show_frame(ConnectPage)
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
def get_page(self, page_name):
return self.frames[page_name]
class ConnectPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
button1 = tk.Button(self, text="SecondPage",
command=lambda: controller.show_frame(EditorPage))
button1.grid(row=2, column=3, padx=15)
class EditorPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.text = CustomText(self, height=25, width=80)
self.text.grid(column=0, row=0, sticky="nw")
self.text.bind("<<TextModified>>", self.onModification)
button2 = tk.Button(self, text="FirstPage",
command=lambda: controller.show_frame(ConnectPage))
button2.grid(row=2, column=3, padx=15)
def onModification(self, event):
print("Yellow!")
class CustomText(tk.Text):
def __init__(self, *args, **kwargs):
"""A text widget that report on internal widget commands"""
tk.Text.__init__(self, *args, **kwargs)
# create a proxy for the underlying widget
self._orig = self._w + "_orig"
self.tk.call("rename", self._w, self._orig)
self.tk.createcommand(self._w, self._proxy)
def _proxy(self, command, *args):
cmd = (self._orig, command) + args
result = self.tk.call(cmd)
if command in ("insert", "delete", "replace"):
self.event_generate("<<TextModified>>")
return result
if __name__ == '__main__':
gui = Texter()
gui.mainloop()
我建议一种更简单的方法。您可以为窗口小部件设置代理,并在该代理内可以检测到何时插入或删除了任何内容。您可以使用该信息来生成虚拟事件,该事件可以像其他任何事件一样绑定。
让我们开始创建一个自定义文本窗口小部件类,您将像使用其他任何文本窗口小部件一样使用它:
import Tkinter as tk
class CustomText(tk.Text):
def __init__(self, *args, **kwargs):
"""A text widget that report on internal widget commands"""
tk.Text.__init__(self, *args, **kwargs)
# create a proxy for the underlying widget
self._orig = self._w + "_orig"
self.tk.call("rename", self._w, self._orig)
self.tk.createcommand(self._w, self._proxy)
def _proxy(self, command, *args):
cmd = (self._orig, command) + args
result = self.tk.call(cmd)
if command in ("insert", "delete", "replace"):
self.event_generate("<<TextModified>>")
return result
此示例中的代理执行三件事:
您可以像使用任何其他文本小部件一样完全使用此小部件,并具有可以绑定到<<TextModified>>
的附加优点。
例如,如果要在文本小部件中显示字符数,可以执行以下操作:
root = tk.Tk()
label = tk.Label(root, anchor="w")
text = CustomText(root, width=40, height=4)
label.pack(side="bottom", fill="x")
text.pack(side="top", fill="both", expand=True)
def onModification(event):
chars = len(event.widget.get("1.0", "end-1c"))
label.configure(text="%s chars" % chars)
text.bind("<<TextModified>>", onModification)
root.mainloop()