wxWidgets/wxPython/demo/wxValidator.py

from wxPython.wx        import *
from wxPython.lib.grids import wxFlexGridSizer

import string

#----------------------------------------------------------------------

ALPHA_ONLY = 1
DIGIT_ONLY = 2

class MyValidator(wxPyValidator):
    def __init__(self, flag=None, pyVar=None):
        wxPyValidator.__init__(self)
        self.flag = flag
        EVT_CHAR(self, self.OnChar)

    def Clone(self):
        return MyValidator(self.flag)

    def Validate(self, win):
        tc = self.GetWindow()
        val = tc.GetValue()
        if self.flag == ALPHA_ONLY:
            for x in val:
                if x not in string.letters:
                    return false

        elif self.flag == DIGIT_ONLY:
            for x in val:
                if x not in string.digits:
                    return false

        return true


    def OnChar(self, event):
        key = event.KeyCode()
        if key < WXK_SPACE or key == WXK_DELETE or key > 255:
            event.Skip()
            return
        if self.flag == ALPHA_ONLY and chr(key) in string.letters:
            event.Skip()
            return
        if self.flag == DIGIT_ONLY and chr(key) in string.digits:
            event.Skip()
            return

        if not wxValidator_IsSilent():
            wxBell()

        # Returning without calling even.Skip eats the event before it
        # gets to the text control
        return

#----------------------------------------------------------------------

class TestValidatorPanel(wxPanel):
    def __init__(self, parent):
        wxPanel.__init__(self, parent, -1)
        self.SetAutoLayout(true)
        VSPACE = 10

        fgs = wxFlexGridSizer(0, 2)

        fgs.Add(1,1);
        fgs.Add(wxStaticText(self, -1, "These controls have validators that limit\n"
                             "the type of characters that can be entered."))

        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)

        label = wxStaticText(self, -1, "Alpha Only: ")
        fgs.Add(label, 0, wxALIGN_RIGHT|wxCENTER)

        fgs.Add(wxTextCtrl(self, -1, "", validator = MyValidator(ALPHA_ONLY)))

        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)

        label = wxStaticText(self, -1, "Digits Only: ")
        fgs.Add(label, 0, wxALIGN_RIGHT|wxCENTER)
        fgs.Add(wxTextCtrl(self, -1, "", validator = MyValidator(DIGIT_ONLY)))

        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)
        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)
        fgs.Add(0,0)
        b = wxButton(self, -1, "Test Dialog Validation")
        EVT_BUTTON(self, b.GetId(), self.OnDoDialog)
        fgs.Add(b)

        border = wxBoxSizer()
        border.Add(fgs, 1, wxGROW|wxALL, 25)
        self.SetSizer(border)
        self.Layout()

    def OnDoDialog(self, evt):
        dlg = TestValidateDialog(self)
        dlg.ShowModal()
        dlg.Destroy()


#----------------------------------------------------------------------

class TextObjectValidator(wxPyValidator):
     """ This validator is used to ensure that the user has entered something
         into the text object editor dialog's text field.
     """
     def __init__(self):
         """ Standard constructor.
         """
         wxPyValidator.__init__(self)



     def Clone(self):
         """ Standard cloner.

             Note that every validator must implement the Clone() method.
         """
         return TextObjectValidator()


     def Validate(self, win):
         """ Validate the contents of the given text control.
         """
         textCtrl = self.GetWindow()
         text = textCtrl.GetValue()

         if len(text) == 0:
             wxMessageBox("A text object must contain some text!", "Error")
             textCtrl.SetFocus()
             return false
         else:
             return true


     def TransferToWindow(self):
         """ Transfer data from validator to window.

             The default implementation returns false, indicating that an error
             occurred.  We simply return true, as we don't do any data transfer.
         """
         return true # Prevent wxDialog from complaining.


     def TransferFromWindow(self):
         """ Transfer data from window to validator.

             The default implementation returns false, indicating that an error
             occurred.  We simply return true, as we don't do any data transfer.
         """
         return true # Prevent wxDialog from complaining.

#----------------------------------------------------------------------

class TestValidateDialog(wxDialog):
    def __init__(self, parent):
        wxDialog.__init__(self, parent, -1, "Validated Dialog")

        self.SetAutoLayout(true)
        VSPACE = 10

        fgs = wxFlexGridSizer(0, 2)

        fgs.Add(1,1);
        fgs.Add(wxStaticText(self, -1,
                             "These controls must have text entered into them.  Each\n"
                             "one has a validator that is checked when the Okay\n"
                             "button is clicked."))

        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)

        label = wxStaticText(self, -1, "First: ")
        fgs.Add(label, 0, wxALIGN_RIGHT|wxCENTER)

        fgs.Add(wxTextCtrl(self, -1, "", validator = TextObjectValidator()))

        fgs.Add(1,VSPACE); fgs.Add(1,VSPACE)

        label = wxStaticText(self, -1, "Second: ")
        fgs.Add(label, 0, wxALIGN_RIGHT|wxCENTER)
        fgs.Add(wxTextCtrl(self, -1, "", validator = TextObjectValidator()))


        buttons = wxBoxSizer(wxHORIZONTAL)
        buttons.Add(wxButton(self, wxID_OK, "Okay"), 0, wxALL, 10)
        buttons.Add(wxButton(self, wxID_CANCEL, "Cancel"), 0, wxALL, 10)

        border = wxBoxSizer(wxVERTICAL)
        border.Add(fgs, 1, wxGROW|wxALL, 25)
        border.Add(buttons)
        self.SetSizer(border)
        border.Fit(self)
        self.Layout()


#----------------------------------------------------------------------

def runTest(frame, nb, log):
    win = TestValidatorPanel(nb)
    return win

#----------------------------------------------------------------------









overview = """\
wxValidator is the base class for a family of validator classes that mediate between a class of control, and application data.

A validator has three major roles:

1. to transfer data from a C++ variable or own storage to and from a control;

2. to validate data in a control, and show an appropriate error message;

3. to filter events (such as keystrokes), thereby changing the behaviour of the associated control.

Validators can be plugged into controls dynamically.

"""