Kivymd Custom Input Dialog. problem with getting text - kivy

Question

I am creating an Input Dialog using kivymd. Whenever I try to fetch the text from the text field, it doesn't output the text, rather it seems like the text is not there. (the dialog just pops up ok and the buttons are working fine).
part of the kivy code
<Content>
MDTextField:
id: pin
pos_hint: {"center_x": 0.5, "center_y": 0.5}
color_mode: 'custom'
line_color_focus: [0,0,1,1]
part of the python code
class Content(FloatLayout):
pass
class MenuScreen(Screen):
def __init__(self, **kwargs):
super(MenuScreen, self).__init__(**kwargs)
def show_confirmation_dialog(self):
# if not self.dialog:
self.dialog = MDDialog(
title="Enter Pin",
type="custom",
content_cls=Content(),
buttons=[
MDFlatButton(
text="cancel",on_release=self.callback
),
MDRaisedButton(
text="[b]ok[/b]",
on_release=self.ok,
markup=True,
),
],
size_hint_x=0.7,
auto_dismiss=False,
)
self.dialog.open()
def callback(self, *args):
self.dialog.dismiss()
def ok(self, *args):
pin = Content().ids.pin.text
if pin == "":
toast("enter pin")
else:
toast(f"pin is {pin}")

Answer 1

You can call the Content class to a variable and use it in the MDDialog.content_cls.
def show_custom_dialog(self):
content_cls = Content() # call the class to a variable
self.cdialog = MDDialog(content_cls=content_cls,
type='custom', title='Enter Pin'
)
self.cdialog.buttons = [
MDFlatButton(text='cancel',on_release=self.close_dialog),
MDRaisedButton(text='Ok',
on_release=lambda x:self.get_data(x,content_cls))
]
self.cdialog.open()
Then create a function that will get the event_button and the content class as arguments by use of lambda expression in the button as shown above.
def get_data(self,instance_btn, content_cls):
textfield = content_cls.ids.pin
# get input
value = textfield._get_text()
# do stufs here
toast(value)
At this point you can extract any id in the Content class.I hope this helps.
Refer below for full code
from kivmd.app import MDApp
from kivymd.uix.floatlayout import MDFloatLayout
from kivymd.uix.dialog import MDDialog
from kivymd.uix.button import MDFlatButton, MDRaisedButtom
from kivy.lang.builder impor Builder
from kivy.toast import toast
kv = '''
MDBoxLayout:
orientation : 'vertical'
MDFlatbutton:
text : 'Dialog'
pos_hint : {'center_x':.5'}
on_release : app.show_custom_dialog()
<Content>:
MDTextField:
id : pin
pos_hint : {'center_x':.5,'center_y':.5}
'''
class Content(MDFloatLayout):
pass
class InputDialogApp(MDApp):
cdialog = None
def build(self):
return Builder.load_string(kv)
def show_custom_dialog(self):
content_cls = Content()
self.cdialog = MDDialog(title='Enter Pin',
content_cls=content_cls,
type='custom')
self.cdialog.buttons = [
MDFlatButton(text="Cancel",on_release=self.close_dialog),
MDRaisedButton(text="Ok",on_release=lambda x:self.get_data(x,content_cls))
]
self.cdialog.open()
def close_dialog(self, instance):
if self.cdialog:
self.cdialog.dismiss()
def get_data(self, instance_btn, content_cls):
textfield = content_cls.ids.pin
value = textfield._get_text()
# do stuffs here
toast(value)
self.close_dialog(instance_btn)
if __name__ == '__main__':
InputDialogApp().run()

Answer 2

I was also having this problem, and the comment by edwin helped a lot. However, one suggestion. instead of formatting it with buttons = [...] inside of MDDialog as opposed to after, like so self.cdialog = MDDialog(..., buttons = [...]) since otherwise the buttons dont show up but other than that it should work!