So im trying to get a variable added to screen and the id fro that is in a widget Im going to add, so if for example I have this:
from kivy.app import App
from kivy.lang import Builder
from kivy.properties import StringProperty
kv = """
Screen:
cal:cal
side: side
GridLayout:
rows: 1
cols:2
spacing:0
GridLayout:
rows: 5
cols:1
Button:
text: "Cube"
# on_press: app.mode = self.text
on_press: app.setMode(self)
Button:
text: "Cuboid"
on_press: app.setMode(self)
Button:
text: "Cylinder"
on_press: app.setMode(self)
Button:
text: "Cone"
on_press: app.setMode(self)
Button:
text: "Sphere"
on_press: app.setMode(self)
FloatLayout:
Label:
text: "The Volume and surface area of a {}:".format(app.mode)
pos_hint: {"x":0.1, "y":0.8}
text_size: self.size
FloatLayout:
id:cal
Label:
text:"Side:"
pos_hint: {"x":1.1, "y":0.7}
text_size: self.size
Label:
text:"Volume:"
pos_hint: {"x":1.1, "y":0.65}
text_size: self.size
Label:
text:"Surface Area:"
pos_hint: {"x":1.1, "y":0.6}
text_size: self.size
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.7}
id: side
text: app.sideText
on_text_validate: app.Cube_on_side_change(self)
Label:
text: app.volume
pos_hint: {"x":1.27, "y":0.65}
text_size: self.size
Label:
text: app.surface_area
pos_hint: {"x":1.355, "y":0.6}
text_size: self.size
"""
cube = """
FloatLayout:
Label:
text:"Side:"
pos_hint: {"x":1.1, "y":0.7}
text_size: self.size
Label:
text:"Volume:"
pos_hint: {"x":1.1, "y":0.65}
text_size: self.size
Label:
text:"Surface Area:"
pos_hint: {"x":1.1, "y":0.6}
text_size: self.size
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.7}
id: side
text: app.sideText
on_text_validate: app.Cube_on_side_change(self)
Label:
text: app.volume
pos_hint: {"x":1.27, "y":0.65}
text_size: self.size
Label:
text: app.surface_area
pos_hint: {"x":1.355, "y":0.6}
text_size: self.size"""
cuboid = """
FloatLayout:
id:main
Label:
text:"Length:"
pos_hint: {"x":1.1, "y":0.7}
text_size: self.size
Label:
text:"Breadth:"
pos_hint: {"x":1.1, "y":0.65}
text_size: self.size
Label:
text:"Height:"
pos_hint: {"x":1.1, "y":0.6}
text_size: self.size
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.7}
id: length
text: app.sideText
on_text_validate: app.Cuboid_on_side_change(self)
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.65}
id: breadth
text: app.sideText
on_text_validate: app.Cube_on_side_change(self)
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.6}
id: height
text: app.sideText
on_text_validate: app.Cuboid_on_side_change()
Label:
text: "Volume:"
pos_hint: {"x":1.1, "y":0.55}
text_size: self.size
Label:
text: "Surface Area:"
pos_hint: {"x":1.1, "y":0.5}
text_size: self.size
Label:
text: app.volume
pos_hint: {"x":1.27, "y":0.55}
text_size: self.size
Label:
text: app.surface_area
pos_hint: {"x":1.355, "y":0.5}
text_size: self.size"""
cone = """
FloatLayout:
Label:
text:"Radius:"
pos_hint: {"x":1.1, "y":0.7}
text_size: self.size
Label:
text:"Height:"
pos_hint: {"x":1.1, "y":0.65}
text_size: self.size
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.7}
id: Radius
text: app.sideText
on_text_validate: app.Cuboid_on_side_change(self)
TextInput:
size_hint: (.4, None)
height: 26
multiline: False
pos_hint: {"x":1.24, "y":0.65}
id: height
text: app.sideText
on_text_validate: app.Cube_on_side_change(self)
Label:
text: "Volume:"
pos_hint: {"x":1.1, "y":0.6}
text_size: self.size
Label:
text: "Surface Area:"
pos_hint: {"x":1.1, "y":0.55}
text_size: self.size
Label:
text: app.volume
pos_hint: {"x":1.27, "y":0.6}
text_size: self.size
Label:
text: app.surface_area
pos_hint: {"x":1.355, "y":0.55}
text_size: self.size
"""
screens = {
"Cube": cube,
"Cuboid": cuboid,
"Cone": cone
}
class MyApp(App):
sideText = StringProperty("")
surface_area = StringProperty("0 cm²")
volume = StringProperty("0 cm³")
mode = StringProperty("Cube")
def build(self):
self.screen = Builder.load_string(kv)
return self.screen
def setMode(self, btn):
self.volume = "0 cm³"
self.surface_area = "0 cm³"
self.mode = btn.text
self.screen.cal.clear_widgets()
self.screen.cal.add_widget(Builder.load_string(screens[self.mode]))
def Cube_on_side_change(self, instance):
try:
value = float(instance.text)
num = True
except ValueError:
# failed to convert
num = False
print("Numbers only idiot.")
def cubeCalc(val):
return {
"volume": val * val * val,
"surface_area": (val * val) * 6
}
if num:
result = cubeCalc(value)
self.volume = "{:.2f} cm³".format(result["volume"])
self.surface_area = "{:.2f} cm²".format(result["surface_area"])
def Cuboid_on_side_change(self):
height = self.screen.cal.ids.main.height.text
try:
value = float(height)
num = True
except ValueError:
# failed to convert
num = False
print("Numbers only idiot.")
def cubeCalc(val):
return {
"volume": val * val * val,
"surface_area": (val * val) * 6
}
if num:
result = cubeCalc(value)
self.volume = "{:.2f} cm³".format(result["volume"])
self.surface_area = "{:.2f} cm²".format(result["surface_area"])
if __name__ == "__main__":
MyApp().run()
on_text_validate of the TextInput with id:height in the string cuboid, I want to get the text from the text input with something like: self.screen.main.height.text, however, to do that I would have to add main:main and height:height to Screen. How would I do this?
I suggest refactoring your code. Rather than re-inventing the capabilities of ScreenManager, just use ScreenManager. In your kv string, replace the FloatLayout with:
ScreenManager:
CubeScreen:
CuboidScreen:
ConeScreen:
and use your additional kv strings (like cube) as the basis for additional rules in your kv string. Something like:
<CubeScreen>:
Label:
text: "The Volume and surface area of a Cube:"
pos_hint: {"x":0.1, "y":0.8}
text_size: self.size
FloatLayout:
Label:
text:"Side:"
pos_hint: {"x":0.1, "y":0.7}
text_size: self.size
.
.
.
And define each Screen class in your py, like:
class CubeScreen(Screen):
def get_cube_area(self):
.
.
.
And in each of the new classes (like CubeScreen) you can define methods for calculating area, volume, etc, and you can access the TextInputs easily using their ids. And your on_text_validate in each Screen can just call the appropriate method from that Screen (like on_text_validate: root.get_cube_area()).