Reputation: 443
Let's say I have a kivy program where the first screen has three buttons, each of which takes you to a different screen. Each of those screens contains a button that takes you to a final screen (the same screen). The final screen has a "back" button. How do I make the "back" button on the final screen take you back to the previous screen (the 1 of 3 mentioned above)? Below is a crude diagram to better help visualize my question.
Screen 1
Start Screen --> Screen 2 --> Final Screen
Screen 3
As of now the "back" button on the final screen takes you back to the Start screen, but this is not what I want.
My python code:
from kivy.app import App
from kivy.uix.screenmanager import Screen, ScreenManager
class MyScreenManager(ScreenManager):
pass
# Branch Screen, takes you to S1, S2, or S3
class BRANCH(Screen):
pass
class S1(Screen):
pass
class S2(Screen):
pass
class S3(Screen):
pass
class FINAL_SCREEN(Screen):
pass
class MAINApp(App):
def build(self):
return MyScreenManager()
if __name__ == '__main__':
MAINApp().run()
My kivy language code:
#:kivy 1.0.9
<MyScreenManager>:
BRANCH:
name: 'branch'
S1:
name: 'screen1'
S2:
name: 'screen2'
S3:
name: 'screen3'
FINAL_SCREEN:
name: 'final_screen'
<BRANCH>
FloatLayout:
Button:
text: 'Screen-1'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.75}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen1'
Button:
text: 'Screen-2'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.40}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen2'
Button:
text: 'Screen-3'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.05}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen3'
<S1>
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'this is SCREEN-1'
color: 1, 1, 1, 1
Button:
text: 'Forward'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
<S2>
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'me este SCREEN-2'
color: 1, 1, 1, 1
Button:
text: 'Onward'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
<S3>
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'something SCREEN-3'
color: 1, 1, 1, 1
Button:
text: 'Lets Go'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
<FINAL_SCREEN>
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'Final Screen'
color: 1, 1, 1, 1
Button:
text: 'Back'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'right'
root.manager.current = 'branch'
Any help or advice is greatly appreciated.
Upvotes: 0
Views: 1447
Reputation: 3048
Here is one solution using a StringProperty on the Final
Screen.
I am setting it when going to the final screen
root.manager.ids.final.previous = root.name
When going back I am using it to go to this screen
root.manager.current = root.previous
This is your whole app
from kivy.app import App
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.lang import Builder
from kivy.properties import StringProperty
kv_str = """
MyScreenManager:
BRANCH:
name: 'branch'
S1:
name: 'screen1'
S2:
name: 'screen2'
S3:
name: 'screen3'
FINAL_SCREEN:
id: final
name: 'final_screen'
<BRANCH>
FloatLayout:
Button:
text: 'Screen-1'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.75}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen1'
Button:
text: 'Screen-2'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.40}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen2'
Button:
text: 'Screen-3'
color: 1.0, 0.6, 0.0, 1
font_size: 30
size_hint_x: 0.50
size_hint_y: 0.25
pos_hint: {'x': 0.20, 'y': 0.05}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'screen3'
<S1>:
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'this is SCREEN-1'
color: 1, 1, 1, 1
Button:
text: 'Forward'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
root.manager.ids.final.previous = root.name
<S2>:
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'me este SCREEN-2'
color: 1, 1, 1, 1
Button:
text: 'Onward'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
root.manager.ids.final.previous = root.name
<S3>:
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'something SCREEN-3'
color: 1, 1, 1, 1
Button:
text: 'Lets Go'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'left'
root.manager.current = 'final_screen'
root.manager.ids.final.previous = root.name
<FINAL_SCREEN>:
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'Final Screen'
color: 1, 1, 1, 1
Button:
text: 'Back'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
root.manager.transition.direction = 'right'
root.manager.current = root.previous
"""
class MyScreenManager(ScreenManager):
pass
# Branch Screen, takes you to S1, S2, or S3
class BRANCH(Screen):
pass
class S1(Screen):
pass
class S2(Screen):
pass
class S3(Screen):
pass
class FINAL_SCREEN(Screen):
previous = StringProperty()
class MAINApp(App):
def build(self):
return Builder.load_string(kv_str)
if __name__ == '__main__':
MAINApp().run()
I tried previous()
as suggested in the comments
<FINAL_SCREEN>:
FloatLayout:
Label:
pos_hint: {'x': 0.00, 'y': 0.20}
font_size: 35
text: 'Final Screen'
color: 1, 1, 1, 1
Button:
text: 'Back'
color: 1.0, 0.6, 0.0, 1
font_size: 20
size_hint_x: 0.20
size_hint_y: 0.20
pos_hint: {'x': 0.40, 'y': 0.15}
on_release:
print(root.manager.previous())
root.manager.current = root.manager.previous()
Strangely, it will always return screen3 and I therefore used the version above.
Upvotes: 2