Kivy RecycleView SelectableButton Does not switch to a Dynamic Layout Page - python-3.x

Question

Am working on a Project that has a RecycleView that contains details of patients.My aim is that when i click on a specific patient on the recycleView row, it should take me to specific dynamic page layout containing specific details of the selected patient in the RecycleView without using the Screen Manager, the switching of dynamic pages.how can i go about this?
i have created a method called change_dynamic_Layout() for switching dynamic pages and it works fine when using the normal button to call it. I have used a print statement in the method to show if the method is executed or not. But when i use the SelectableButton,the print statement is executed but the statement for changing page-layout is not. No errors is shown and the dynamic page does not change. Here is the code try to run it and see what am talking about?
Demo.py
from kivy.app import App
from kivy.properties import ObjectProperty, StringProperty, ListProperty,
NumericProperty
from kivy.uix.behaviors import ButtonBehavior
from kivy.graphics import Color, Rectangle
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from kivy.factory import Factory
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.properties import BooleanProperty
from kivy.uix.recycleboxlayout import RecycleBoxLayout
from kivy.uix.recyclegridlayout import RecycleGridLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
lost = Builder.load_file('Demo.kv')
class SelectableRecycleGridLayout(FocusBehavior, LayoutSelectionBehavior,
RecycleGridLayout):
''' Adds selection and focus behaviour to the view. '''
class SelectableButton(RecycleDataViewBehavior, Button):
''' Add selection support to the Label '''
index = None
selected = BooleanProperty(False)
selectable = BooleanProperty(True)
def refresh_view_attrs(self, rv, index, data):
''' Catch and handle the view changes '''
self.index = index
return super(SelectableButton, self).refresh_view_attrs(
rv, index, data)
def on_touch_down(self, touch):
''' Add selection on touch down '''
if super(SelectableButton, self).on_touch_down(touch):
return True
if self.collide_point(*touch.pos) and self.selectable:
return self.parent.select_with_touch(self.index, touch)
def apply_selection(self, rv, index, is_selected):
''' Respond to the selection of items in the view. '''
self.selected = is_selected
#selectablebutton to call the change_dynamic_Layout() method in patient class
def on_enter(self):
layout=Patient()
layout.change_dynamic_Layout()
class victor(BoxLayout):
pass
class Patient(Screen):
manage_prescription: ObjectProperty(None)
#Method to change the dynamic pagelayout
def change_dynamic_Layout(self):
layout = Factory.victor()
self.manage_prescription.clear_widgets()
self.manage_prescription.add_widget(layout)
print ('pressed')
class DemoApp(App):
title = 'Hospital Management System'
def build(self):
n= Patient()
return n
if __name__ == "__main__":
DemoApp().run()
demo.kv
<Patient>:
manage_prescription:manage_prescription
BoxLayout:
GridLayout :
cols:1
BoxLayout:
id:manage_prescription
orientation:'vertical'
BoxLayout:
size_hint_y:None
height:40
Button:
text:"NO."
font_size: 25
Button:
text:"Date"
font_size: 25
Button:
text:"Patient"
font_size: 25
Button:
text:"Doctor"
font_size: 25
on_press: root.change_dynamic_Layout()
BoxLayout:
RecycleView:
bar_width: 10
bar_color: 1, 0, 0, 1 # red
bar_inactive_color: 0, 0, 1, 1 # blue
#effect_cls: "ScrollEffect"
scroll_type: ['bars']
viewclass: 'SelectableButton'
data:[{'text': str(x)} for x in range(20)]
SelectableRecycleGridLayout:
cols:4
default_size: None, dp(56)
default_size_hint:1, None
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
multiselect: True
touch_multiselect: True
<victor>:
Label:
text:" Switched to specific page for patient's details"
<SelectableButton>:
# Draw a background to indicate selection
canvas.before:
Color:
rgba: (.0, 0.9, .1, .3) if self.selected else (1, 1, 1, 1)
Rectangle:
pos: self.pos
size: self.size
on_press: root.on_enter()
Any insight or help is much appreciated, thanks in advance.

Answer 1

The problem is that your on_enter method of the SelectableButton is creating a new Patient layout (Screen), and calling the change_dynamic_Layout method of that new Patient Screen. That newly created Patient Screen is not the one displayed in your app, so it has no effect on what you see. You actually want to call change_dynamic_Layout on the displayed Patient Screen. One way of doing this is to access it via App.get_running_app().root. So that your on_enter method can be changed to:
def on_enter(self):
#layout=Patient()
layout = App.get_running_app().root
layout.change_dynamic_Layout()
Here is the entire python file:
from kivy.app import App
from kivy.properties import ObjectProperty, StringProperty, ListProperty, NumericProperty
from kivy.uix.behaviors import ButtonBehavior
from kivy.graphics import Color, Rectangle
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from kivy.factory import Factory
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.properties import BooleanProperty
from kivy.uix.recycleboxlayout import RecycleBoxLayout
from kivy.uix.recyclegridlayout import RecycleGridLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
lost = Builder.load_file('Demo.kv')
class SelectableRecycleGridLayout(FocusBehavior, LayoutSelectionBehavior,
RecycleGridLayout):
''' Adds selection and focus behaviour to the view. '''
class SelectableButton(RecycleDataViewBehavior, Button):
''' Add selection support to the Label '''
index = None
selected = BooleanProperty(False)
selectable = BooleanProperty(True)
def refresh_view_attrs(self, rv, index, data):
''' Catch and handle the view changes '''
self.index = index
return super(SelectableButton, self).refresh_view_attrs(
rv, index, data)
def on_touch_down(self, touch):
''' Add selection on touch down '''
if super(SelectableButton, self).on_touch_down(touch):
return True
if self.collide_point(*touch.pos) and self.selectable:
return self.parent.select_with_touch(self.index, touch)
def apply_selection(self, rv, index, is_selected):
''' Respond to the selection of items in the view. '''
self.selected = is_selected
#selectablebutton to call the change_dynamic_Layout() method in patient class
def on_enter(self):
#layout=Patient()
layout = App.get_running_app().root
layout.change_dynamic_Layout()
class victor(BoxLayout):
pass
class Patient(Screen):
manage_prescription: ObjectProperty(None)
#Method to change the dynamic pagelayout
def change_dynamic_Layout(self):
layout = Factory.victor()
self.manage_prescription.clear_widgets()
self.manage_prescription.add_widget(layout)
print ('pressed')
class DemoApp(App):
title = 'Hospital Management System'
def build(self):
n= Patient()
return n
if __name__ == "__main__":
DemoApp().run()
And here is the Demo.kv:
<Patient>:
manage_prescription:manage_prescription
BoxLayout:
GridLayout :
cols:1
BoxLayout:
id:manage_prescription
orientation:'vertical'
BoxLayout:
size_hint_y:None
height:40
Button:
text:"NO."
font_size: 25
Button:
text:"Date"
font_size: 25
Button:
text:"Patient"
font_size: 25
Button:
text:"Doctor"
font_size: 25
on_press: root.change_dynamic_Layout()
BoxLayout:
RecycleView:
bar_width: 10
bar_color: 1, 0, 0, 1 # red
bar_inactive_color: 0, 0, 1, 1 # blue
#effect_cls: "ScrollEffect"
scroll_type: ['bars']
viewclass: 'SelectableButton'
data:[{'text': str(x)} for x in range(20)]
SelectableRecycleGridLayout:
cols:4
default_size: None, dp(56)
default_size_hint:1, None
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
multiselect: True
touch_multiselect: True
<victor>:
Label:
text:" Switched to specific page for patient's details"
<SelectableButton>:
# Draw a background to indicate selection
canvas.before:
Color:
rgba: (.0, 0.9, .1, .3) if self.selected else (1, 1, 1, 1)
Rectangle:
pos: self.pos
size: self.size
on_press: root.on_enter()