I'm trying to build an App thats uses certain input Parameters and when hitting a submit button it uses a logic to generate output paramters. I managed to build the app and the input and the triggering via a submit button. Now i want to generate the output, for beginning with an easy logic. I looked up several similar solutions, but somehow they don't work for me. For some reason my .kv file doen't get the updated value for the label text with the error: "ValueError: Label.text accept only str" Eventough everything is declared as a string in the .py. If i change it in the kv to str("...") I get some code line which i guess is the intern id of the attribute but not the assigned value i want to get. I hope you can help. Pls don't be too harsh, I#M new to python and kivy...
main .py, shuldn't be part of the problem Peenomat.py
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.anchorlayout import AnchorLayout
from kivy.core.text import LabelBase
Builder.load_file('Statusbar.kv')
Builder.load_file('Inputparameters.kv')
Builder.load_file('Outputparameters.kv')
#Layout
class Peenomat(AnchorLayout):
pass
class PeenomatApp(App):
def build(self):
return Peenomat()
if __name__=="__main__":
PeenomatApp().run()
.py with the classes and methods for the logic StatusBar.py
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from kivy.properties import ObjectProperty
from kivy.properties import StringProperty
from kivy.app import App
class InputParameters(GridLayout):
verfahren = ObjectProperty(None)
def on_state(self, togglebutton):
tb = togglebutton
if tb.state == 'down':
self.verfahren = tb.text
self.verfahren = tb.text
print(self.verfahren)
return self.verfahren
class StatusBar(BoxLayout):
#InputGrößen
group_mode = False
prozess = ObjectProperty(None)
vorbehandlung = ObjectProperty(None)
material = ObjectProperty(None)
haerte = ObjectProperty(None)
rauheit = ObjectProperty(None)
#OutputGrößen
frequenz = StringProperty(None)
def btn_submit(self):
ip = App.get_running_app().root.ids._input_parameters
print("Haerte:", ip.haerte.value, "Rauheit:", ip.rauheit.value, "Material:", ip.material.text, "Vorbehandlung:", ip.vorbehandlung.text)
if ip.haerte.value < 50:
self.frequency = str(180)
elif ip.haerte.value < 60:
self.frequency = str(200)
else:
self.frequency = str(220)
#control to see if right value is taken
print(self.frequency, "Hz")
def btn_clear(self):
np = App.get_running_app().root.ids._input_parameters
np.pro1.state = "normal"
np.pro2.state = "normal"
np.pro3.state = "normal"
np.material.text = "Auswahl treffen"
np.haerte.value = 55
np.rauheit.value = 5.5
the .kv file that can't get the label text: outputparameters.kv
#: import statusbar StatusBar
<OutputParameters@GridLayout>
#Initialisierung .py zu .kv
frequenz: _frequenz
Label:
text:'Frequenz:'
font_size:
Label:
id: _frequenz
text: root.frequenz
font_size: 20
the .kv file with the submit button, shouldn't be part of the problem either, worked perfectly fine before implementing the part ehre i try to update the text statusbar.kv
#: import statusbar StatusBar
<StatusBar@BoxLayout>
orientation:'horizontal'
Button:
text: 'Clear'
on_press: root.btn_clear()
Button:
text: 'Submit'
on_press: root.btn_submit()
the file where i put in all the inputparameters, rather important: Inputparameters.kv
#: import statusbar StatusBar
<InputParameters@GridLayout>
#Initialisierung .py zu .kv Ids
prozess: _prozess
pro1: _prozess1
pro2: _prozess2
pro3: _prozess3
vorbehandlung: _vorbehandlung
material: _material
haerte: _haerte
rauheit: _rauheit
#Prozess
Label:
text:'Prozess:
BoxLayout:
orientation: 'horizontal'
id: _prozess
ToggleButton:
id:_prozess1
text:'P-MOH'
group: "proc_group"
on_state: root.on_state(self)
ToggleButton:
id:_prozess2
text:'E-MOH'
group: "proc_group"
on_state: root.on_state(self)
ToggleButton:
id:_prozess3
text:'PE-MOH'
group: "proc_group"
on_state: root.on_state(self)
#Material
Label:
text: 'Material:'
Spinner:
id: _material
text: ""
values:
# Herstellschritte
Label:
text:'Fertigungsschritte:'
Spinner:
id: _vorbehandlung
text:
values:
# Haerte
Label:
text:'Haerte:'
BoxLayout:
orientation: 'vertical'
Label:
text: str(_haerte.value)
Slider:
id: _haerte
# Rauheit
Label:
text:'Rauheit:
BoxLayout:
orientation: 'vertical'
Label:
text:
Slider:
id: _rauheit
and the file where my layout is embedded (also rather necessary) peenomat.kv
<Peenomat>
AnchorLayout:
anchor_x: 'left'
anchor_y: 'bottom'
GridLayout:
cols: 1
canvas.before:
Color:
Rectangle:
pos: self.pos
size: self.size
InputParameters:
id:_input_parameters
StatusBar:
id:_status_bar
OutputParameters:
id:_output_parameters
I really hope you can help, have been struggeling with this for a while and it should rather be easy...thanks in advance!
In your kv rule for <OutputParameters@GridLayout> you have a line:
frequenz: _frequenz
which sets frequenz to be a reference to the Label with the id of _frequenz. Then in that Label you are setting text using:
text: root.frequenz
So, you are trying to set the text of the Label to a reference to that Label
I suggest trying something like this:
<OutputParameters@GridLayout>
#Initialisierung .py zu .kv
frequenz: _frequenz
frequency: ''
And change the Label to:
Label:
id: _frequenz
text: root.frequency
font_size: 20
But to actually change the value shown in the label, you will need a reference to the instance of OutputParameters, using something like:
App.get_running_app().root.ids._output_parameters.frequency = str(500)