We Keep Coding

How to reference other class methods in kivy

I'm new to stack overflow but I've been programming in python for a couple years. One thing I havent done much of is object oriented programming. I just started learning kivy and I think I might have screwed up the root of my program by organizing it wrong. I used classes to define each label, button, layout...etc. now I'm wondering how I can reference the attributes of each text input to use what's filled in for other methods I want to define.
Example: have a button when pressed gets the input from two different text inputs and adds them together and a label displays it.
You can see what I've tried in my code but I'm having a hell of a time figuring out how to reference all these things from different classes.
I hope my code is understandable...sorry its lengthy but I want you to see the whole scope of what I did. I'm really hoping I can get a solution to where I can keep my organization and have certain things only show up under their own files but I understand if I have to change a lot of things...
Main.py
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.label import Label
from kivy.uix.tabbedpanel import TabbedPanel
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import ObjectProperty
from kivy.uix.gridlayout import GridLayout
from kivy.uix.anchorlayout import AnchorLayout
from kivy.uix.togglebutton import ToggleButton
from kivy.uix.relativelayout import RelativeLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.screenmanager import ScreenManager, Screen
from os import listdir
from kivy.core.window import Window
#load all files with 'kv' in folder
kv_path = './kv/'
for kv in listdir(kv_path):
Builder.load_file(kv_path+kv)
#move the keyboard below text input
Window.softinput_mode = 'below_target'
#classes for savings and loan screens
class SaveButton(Button):
pass
class LoanButton(Button):
pass
class Calculate(Button):
def add(self):
total = SaveDepositInput.inideposit +GoalAmountInput.amount
return total
pass
class TotalsLabel(Label):
pass
#layout classes
class MainBoxLayout(BoxLayout):
pass
class InsideAnchorLayout(AnchorLayout):
pass
class OneColGridlayout(GridLayout):
pass
class AColGridLayout(GridLayout):
pass
class TwoColGridLayout(GridLayout):
pass
class WidgetRelativeLayout(RelativeLayout):
pass
#Toggle Buttons
class DailyToggle(ToggleButton):
pass
class WeeklyToggle(ToggleButton):
pass
class BiWeeklyToggle(ToggleButton):
pass
class MonthlyToggle(ToggleButton):
pass
class YearlyToggle(ToggleButton):
pass
class NoneToggle(ToggleButton):
pass
class Monthly2Toggle(ToggleButton):
pass
class Yearly2Toggle(ToggleButton):
pass
#classes for screen change
class SaveScreen(Screen):
pass
class LoanScreen(Screen):
pass
class SaveLoanTabs(TabbedPanel):
pass
#classes for savings screen
class OutputLabel(Label):
pass
class GoalOutputLabel(Label):
pass
class NoReinvestLabel(Label):
pass
class SaveInstructLabel(Label):
pass
class SaveDepositLabel(Label):
pass
class SaveDepositInput(TextInput):
def inideposit(self):
initial = root.TextInput.text
deposit = int(initial)
return deposit
pass
class SaveYearsLabel(Label):
pass
class SaveYearsInput(TextInput):
pass
class SaveMonthsInput(TextInput):
pass
class ChooseCompoundLabel(Label):
pass
class SaveInterestLabel(Label):
pass
class SaveInterestInput(TextInput):
pass
class RepeatDepositLabel(Label):
pass
class RepeatDeposit2Label(Label):
pass
class RepeatDepositInput(TextInput):
pass
class YearsLabel(Label):
pass
class MonthsLabel(Label):
pass
class GoalAmount(Label):
pass
class GoalAmountInput(TextInput):
def amount(self):
initial = root.TextInput.text
goal = int(initial)
return goal
pass
#classes for loan screen
class LoanOutputLabel(Label):
pass
class LoanInstructLabel(Label):
pass
class LoanAmountLabel(Label):
pass
class LoanAmountInput(TextInput):
pass
# Create the screen manager
sm = ScreenManager()
sm.add_widget(SaveScreen(name='save'))
sm.add_widget(LoanScreen(name='loan'))
#class to run app
class InterestApp(App):
def build(self):
self.title = "Compound Interest and Loan Application"
return sm
#run app
if __name__ == "__main__":
InterestApp().run()
Main.kv file(mostly used for layout formatting)
<SaveScreen>:
MainBoxLayout:
GridLayout:
cols: 2
SaveButton:
on_press: root.manager.current = 'save'
LoanButton:
on_press: root.manager.current = 'loan'
InsideAnchorLayout:
GridLayout:
cols: 1
canvas:
Color:
rgba: .7,1,.7,1
Rectangle:
size: self.size
pos: self.pos
SaveInstructLabel:
InsideAnchorLayout:
TwoColGridLayout:
SaveDepositLabel:
SaveDepositInput:
InsideAnchorLayout:
AColGridLayout:
ChooseCompoundLabel:
InsideAnchorLayout:
AColGridLayout:
cols: 3
DailyToggle:
MonthlyToggle:
YearlyToggle:
InsideAnchorLayout:
TwoColGridLayout:
SaveInterestLabel:
SaveInterestInput:
InsideAnchorLayout:
AColGridLayout:
RepeatDepositLabel:
InsideAnchorLayout:
AColGridLayout:
cols: 5
NoneToggle:
WeeklyToggle:
BiWeeklyToggle:
Monthly2Toggle:
Yearly2Toggle:
InsideAnchorLayout:
TwoColGridLayout:
RepeatDeposit2Label:
RepeatDepositInput:
InsideAnchorLayout:
TwoColGridLayout:
size_hint_y: None
height: dp(50)
SaveYearsLabel:
TwoColGridLayout:
YearsLabel:
SaveYearsInput:
MonthsLabel:
SaveMonthsInput:
InsideAnchorLayout:
TwoColGridLayout:
GoalAmount:
GoalAmountInput:
InsideAnchorLayout:
GridLayout:
cols: 1
canvas:
Color:
rgba: .5,1,1,1
Rectangle:
size: self.size
pos: self.pos
size_hint: None, None
height: dp(80)
width: self.parent.width - dp(15)
TotalsLabel:
OutputLabel:
GoalOutputLabel:
NoReinvestLabel:
InsideAnchorLayout:
AColGridLayout:
Calculate:
<LoanScreen>:
MainBoxLayout:
TwoColGridLayout:
SaveButton:
on_press: root.manager.current = 'save'
LoanButton:
on_press: root.manager.current = 'loan'
Buttons.kv
<SaveButton>:
id: 'save'
text: "[u]Save[/u]"
color: 1, .9, 0, 1
background_normal: ''
background_color: (.5, .5, .5, 1) if self.state == 'normal' else (0, .75, 1, 1)
group: 'menu'
markup: True
<LoanButton>:
text: "[u]Loan[/u]"
markup: True
color: 1, .9, 0, 1
background_normal: ''
background_color: (.5, .5, .5, 1) if self.state == 'normal' else (0, .75, 1, 1)
group: 'menu'
<DailyToggle>:
text: 'Daily'
group: 'compound'
<MonthlyToggle>:
text: 'Monthly'
group: 'compound'
<YearlyToggle>:
text: 'Yearly'
group: 'compound'
<WeeklyToggle>:
text: 'Weekly'
group: 'repeat'
<Yearly2Toggle>:
text: 'Yearly'
group: 'repeat'
<Monthly2Toggle>:
text: 'Monthly'
group: 'repeat'
<BiWeeklyToggle>:
text: 'Bi-Weekly'
group: 'repeat'
<NoneToggle>:
text: 'None'
group: 'repeat'
<Calculate>:
text: '[u][b]Calculate[/b][/u]'
markup: True
on_release: self.add
Labels.kv
<SaveInstructLabel>:
text: "[b]This is the Savings screen. It will calculate compounded interest over a period of time and tell you the result. Follow each prompt to calculate.[/b]"
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
markup: True
<SaveDepositLabel>:
text: "Enter initial deposit amount:"
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<ChooseCompoundLabel>:
text: "Choose frequency of compounding interest:"
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<SaveInterestLabel>:
text: 'Enter the interest APY:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<RepeatDepositLabel>:
text: 'How often will you make a deposit:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<SaveYearsLabel>:
text: 'Enter the amount of years and months you will have this account build:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
font_size: dp(15)
<YearsLabel>:
text: 'Years:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'right'
color: 0,0,0,1
<MonthsLabel>:
text: 'Months:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'right'
color: 0,0,0,1
<GoalAmount>:
text: '(Optional)Enter an amount you would like to reach:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<OutputLabel>:
text: app.Calculate.add
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<GoalOutputLabel>:
text: 'total years to reach goal'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<NoReinvestLabel>:
text: 'if you didnt reinvest'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<TotalsLabel>:
text: '[u][b]TOTALS:[/b][/u]'
markup: True
valign: 'middle'
halign: 'center'
color: 0,0,0,1
<RepeatDeposit2Label>:
text: 'Enter recurring deposit amount:'
text_size: root.width, None
size: self.texture_size
valign: 'middle'
halign: 'center'
color: 0,0,0,1
Textboxes.kv
<SaveDepositInput>:
multiline: False
hint_text: '$0.00'
input_filter: 'float'
size_hint_y: None
height: dp(25)
<SaveInterestInput>:
multiline: False
hint_text: '0.0'
input_filter: 'float'
size_hint_y: None
height: dp(25)
<SaveYearsInput>:
multiline: False
hint_text: '0'
input_filter: 'int'
size_hint_y: None
height: dp(25)
<SaveMonthsInput>:
multiline: False
hint_text: '0'
input_filter: 'int'
size_hint_y: None
height: dp(25)
<GoalAmountInput>:
multiline: False
hint_text: '$0.00'
input_filter: 'float'
size_hint_y: None
height: dp(25)
<RepeatDepositInput>:
multiline: False
hint_text: '$0.00'
input_filter: 'float'
size_hint_y: None
height: dp(25)
And Layouts.kv
<MainBoxLayout>:
spacing: dp(2)
orientation: 'vertical'
canvas.before:
Color:
rgba: .7,1,.7,1
Rectangle:
size: self.size
pos: self.pos
<TwoColGridLayout>:
cols: 2
size_hint: .95, .70
canvas:
Color:
rgba: .5,1,1,1
Rectangle:
size: self.size
pos: self.pos
<OneColGridLayout>:
cols: 1
<AColGridLayout>:
cols: 1
size_hint: .95,.70
canvas:
Color:
rgba: .5,1,1,1
Rectangle:
size: self.size
pos: self.pos
<WidgetRelativeLayout>:
<InsideAnchorLayout>:
anchor_x: 'center'

In your Calculate Button, the add method is trying to call static methods, but the methods you name are actually instance methods. So you need to call them as instance methods. That means that you must have the instances of SaveDepositInput and GoalAmountInput. Since all of these things are in your SaveScreen, you can easily reference them using ids. To do this you cn add an id to SaveDepositInput in your SaveScreen:
InsideAnchorLayout:
TwoColGridLayout:
SaveDepositLabel:
SaveDepositInput:
id: save_deposit_input
and for the GoalInputAmount:
InsideAnchorLayout:
TwoColGridLayout:
GoalAmount:
GoalAmountInput:
id: goal_amount_input
then, in order to access these from the Calculate Button:
InsideAnchorLayout:
AColGridLayout:
Calculate:
gai: goal_amount_input
sdi: save_deposit_input
Then, the CalculateButton class becomes:
class Calculate(Button):
def add(self):
total = self.sdi.inideposit() + self.gai.amount()
return total
A couple other issues. The CalculateButton in your Buttons.kv should be:
<Calculate>:
text: '[u][b]Calculate[/b][/u]'
markup: True
on_release: self.add()
( you were missing the ())
And you have a similar class vs instance issue with your OutputLabel in your Labels.kv.

Kivy Buttons and Labels size based on display size

I'm trying to figure out how to make my buttons and labels fix perfectly depending on my display size. So if the phone display is different, it will always be in fixed size.
Python Code:
import kivy
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
class OpeningScreen(Screen):
pass
class LoginScreen(Screen):
pass
class SignupScreen(Screen):
pass
class ScreenManagement(ScreenManager):
pass
AppKv = Builder.load_file("App.kv")
class MyApp(App):
def build(self):
return AppKv
if __name__ == '__main__':
MyApp().run()
Kv code:
#: import FadeTransition kivy.uix.screenmanager.FadeTransition
#: import hex kivy.utils.get_color_from_hex
#------------------------------------------------------------#
ScreenManagement:
transition: FadeTransition()
OpeningScreen:
LoginScreen:
SignupScreen:
#------------------------------------------------------------#
<OpeningScreen>:
name: "OpeningScreen"
canvas:
Color:
rgb: 1, 1, 1
Rectangle:
pos: self.pos
size: self.size
Label:
text: "Welcome"
color: 1,1,1,1
font_size: 45
size_hint: 0.2,0.1
pos_hint: {"x":0.40, "top":0.995}
Button:
size: 100,75
on_release: app.root.current = "LoginScreen"
text: "Login"
font_size: 50
color: 1,1,1,1
background_color: (0,0,0,1)
background_normal: ""
background_down: ""
size_hint: 0.3,0.2
pos_hint: {"x":0.35, "top":0.7}
Button:
size: 100,75
on_release: app.root.current = "SignupScreen"
text: "Sign up"
font_size: 50
color: 1,1,1,1
background_color: (0,0,0,1)
background_normal: ""
background_down: ""
size_hint: 0.3,0.2
pos_hint: {"x":0.35, "top":0.4}
#------------------------------------------------------------#
<LoginScreen>:
name: "LoginScreen"
canvas:
Color:
rgb: 1, 1, 1
Rectangle:
pos: self.pos
size: self.size
Label:
text: "Login In"
color: 0,0,0,1
font_size: 45
size_hint: 0.2,0.1
pos_hint: {"x":0.40, "top":0.995}
#------------------------------------------------------------#
<SignupScreen>:
name: "SignupScreen"
canvas:
Color:
rgb: 1, 1, 1
Rectangle:
pos: self.pos
size: self.size
Label:
text: "Sign Up"
color: 0,0,0,1
font_size: 45
size_hint: 0.2,0.1
pos_hint: {"x":0.40, "top":0.995}
I would really appreciate if anyone could help me with this. I was trying to find out how to do this but I couldn't

Button and Label sizes can be set using several different approaches:
Use Kivy Metrics. You can set sizes using dp (for example dp(100)), this is a Density-independent Pixel size. There is also a sp (used similarly) that is Scale-independent Pixels (normally used for font sizes)
Use self.texture_size. You can set sizes using this as size: self.texture_size. This will make your Button and Label widgets just large enough to fit the text in it. You can add some padding by using something like:
width: self.texture_size[0] + dp(10)
height: self.texture_size[1] + dp(10)
Use size_hint. This will ensure that the Button and Label widgets take up the same percentage of your display, regardless of the device.
Don't forget to set size_hint to None, None for the first two above to work.

Boxlayouts in Scrollview

I would like to ask your help.
The scrollable structure under the link is what I want to generate.
As the Scrollview accept only one element, I used a GridLayout. Somehow I cannot put any Boxlayout in the GridLayout.
Could you help me? Did I made a mistake? Should I use maybe an other Layout? if yes, which one?
Thank you.
Here is the output of my .kv file: http://imgur.com/etilRPg
Here is the result, if I change cols:1 to cols:2 : http://imgur.com/ihWla4Y
Here is the code I tried in the .kv file:
#:kivy 1.8.0
RootWidget:
# import container
container: container
# fill container
BoxLayout:
id: container
orientation: 'vertical'
padding: 0
spacing: 3
ScrollView:
size_hint: 1, 1
pos_hint: {'center_x': .5, 'center_y': .5}
GridLayout:
cols: 1
padding: 0
spacing: 3
size_hint: 1, None
height: self.minimum_height
do_scroll_x: False
BoxLayout:
height: 260
orientation: 'horizontal'
canvas.before:
Color:
rgb: 0.7, 0.7, 0.9
Rectangle:
size: self.size
pos: self.pos
BoxLayout:
height: 260
orientation: 'horizontal'
canvas.before:
Color:
rgb: 0.7, 0.7, 0.9
Rectangle:
size: self.size
pos: self.pos
BoxLayout:
height: 260
orientation: 'horizontal'
canvas.before:
Color:
rgb: 0.7, 0.7, 0.9
Rectangle:
size: self.size
pos: self.pos
#type
Label:
height: 260
size_hint: 1, None
text: 'Typ'
BoxLayout:
height: 260
orientation: 'horizontal'
canvas.before:
Color:
rgb: 0.7, 0.7, 0.9
Rectangle:
size: self.size
pos: self.pos

If you want to set height or width or anything else with sizing you need to do something first in a widget you want to set it for:
size_hint: None, None
This will disable setting those properties according to parent's size and some other stuff i.e. number of widgets in parent (three widgets = parent's size / 3 for each) at least for layouts such as BoxLayout or GridLayout. Check docs for more.
Alternatively use size_hint_x: None or size_hint_y: None and let the other part be set automatically if you only want to set one of height or width.

Kivy (kv language) StackLayout Issue and Boundary Issue

I'm new to Kivy and still working out the best way to use it. Currently, I'm taking an example from their repo (textsize demo) and attempting to use layout concepts in a personal project.
At the end of the day, all I want is a "navbar" at the top of my screen and a content section below it. At the moment, I'm trying to accomplish this with a BoxLayout which includes a StackLayout (nav items) and a GridLayout (other content).
My Code Snippet:
<WindowWidget>:
BoxLayout:
orientation: 'vertical'
StackLayout:
Label:
text: 'Test1'
Label:
text: 'Test1.1'
Label:
text: 'Test2'
This code produces this: Kivy Screenshot.
I don't understand why label 1.1 is pushed down on top of label 2 rather than appearing beside label 1.
I added the following code taken from the kivy examples hoping the height setting would add some clarity, but I get the error below:
Code:
<StackLayout>:
size_hint_y: None
spacing: dp(6)
padding: dp(6), dp(4)
height: self.minimum_height
Error:
Warning, too much iteration done before the next frame. Check your
code, or increase the Clock.max_iteration attribute
This is caused by my inclusion of the "height: self.minimum_height" line. However, this works in the demo, so I'm not sure how I managed to screw it up. I'll include the example's kv code below for reference.
The original:
BoxLayout:
orientation: 'vertical'
HeadingLabel:
text: 'These modify all demonstration Labels'
StackLayout:
# Button is a subclass of Label and can be sized to text in the same way
Button:
text: 'Reset'
on_press: app.reset_words()
ToggleButton:
text: 'Shorten'
on_state:
app.shorten=self.state=='down'
ToggleButton:
text: 'max_lines=3'
on_state:
app.max_lines=3 if self.state=='down' else 0
Spinner:
text: 'bottom'
values: 'bottom', 'middle', 'top'
on_text: app.valign=self.text
Spinner:
text: 'left'
values: 'left', 'center', 'right', 'justify'
on_text: app.halign=self.text
GridLayout:
id: grid_layout
cols: 2
height: cm(6)
size_hint_y: None
HeadingLabel:
text: "Default, no text_size set"
HeadingLabel:
text: 'text_size bound to size'
DemoLabel:
id: left_content
disabled_color: 0, 0, 0, 0
DemoLabel:
id: right_content
text_size: self.size
padding: dp(6), dp(6)
ToggleButton:
text: 'Disable left'
on_state:
left_content.disabled=self.state=='down'
# Need one Widget without size_hint_y: None, so that BoxLayout fills
# available space.
HeadingLabel:
text: 'text_size width set, size bound to texture_size'
text_size: self.size
size_hint_y: 1
DemoLabel:
id: bottom_content
# This Label wraps and expands its height to fit the text because
# only text_size width is set and the Label size binds to texture_size.
text_size: self.width, None
size: self.texture_size
padding: mm(4), mm(4)
size_hint_y: None
# The column heading labels have their width set by the parent,
# but determine their height from the text.
<HeadingLabel#Label>:
bold: True
padding: dp(6), dp(4)
valign: 'bottom'
height: self.texture_size[1]
text_size: self.width, None
size_hint_y: None
<ToggleButton,Button>:
padding: dp(10), dp(8)
size_hint: None, None
size: self.texture_size
# This inherits Button and the modifications above, so reset size
<Spinner>:
size: sp(68), self.texture_size[1]
<DemoLabel#Label>:
halign: app.halign
valign: app.valign
shorten: app.shorten
max_lines: app.max_lines
canvas:
Color:
rgb: 68/255.0, 164/255.0, 201/255.0
Line:
rectangle: self.x, self.y, self.width, self.height
<StackLayout>:
size_hint_y: None
spacing: dp(6)
padding: dp(6), dp(4)
height: self.minimum_height
TYIA

How to bind using kivy only?

I want to create a Widget changing only the text of a label inside it, but all the ways I find how to change this are by changing it in the python code instead of reusing only Kivy objects.
So I have a widget like the following:
<AmiLabel#Label>
color: .1, .5, .8, 1
font_size: 16
<AmiTextInput#TextInput>
font_size: 16
<PropertyInputForm>:
BoxLayout:
size: root.size
pos: root.pos
orientation: 'horizontal'
AmiLabel:
text: 'Folder Location'
size_hint_x: .5
AmiTextInput:
text: 'None'
size_hint_x: .5
<MainFormWidget>:
BoxLayout:
size: root.size
pos: root.pos
id: foo_bar
padding: 5
spacing: 5
canvas:
Color:
rgb: (1, 1, 1)
Rectangle:
pos: self.pos
size: self.size
orientation: 'vertical'
AmiLabel:
height: 36
size_hint_x: 1
size_hint_y: None
text: 'Project Name'
PropertyInputForm:
height: 36
size_hint_x: 1
size_hint_y: None
# I WANT TO CHANGE THE TEXT OF THE LABEL IN HERE
PropertyInputForm:
height: 36
size_hint_x: 1
size_hint_y: None
# I WANT TO CHANGE THE TEXT OF THE LABEL IN HERE
All I want to is change the text of the label from another widget in another level without touching the python code.
¿Is that possible?

One simple way would be to add a new property to your PropertyInputForm and reference or set that.
<PropertyInputForm>:
new_text_property: ''
BoxLayout:
size: root.size
pos: root.pos
orientation: 'horizontal'
AmiLabel:
text: root.new_text_property
size_hint_x: .5
AmiTextInput:
text: 'None'
size_hint_x: .5
and later
PropertyInputForm:
height: 36
size_hint_x: 1
size_hint_y: None
new_text_property: 'whatever'
You may also need to declare new_text_property in the python class to have it be a StringProperty rather than an ObjectProperty, though even that is I think not necessary in kivy 1.8.