How to put multiple columns into a kivy RecycleView?

Question

I want to put the data of a (csv-)table into a kivy recycleview.

I managed to insert multiple columns with one row, if i assign a fixed text to the Labels in the kv, but i can't get it to fill the labels with data from a dictionary list. This is the code so far, that i use to test the concept:

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.boxlayout import BoxLayout
import csv

items = [{'SP1': 'Artikelnummer', 'SP2': 'Name', 'SP3': 'Groesse'},
    {'SP1': '510001', 'SP2': 'Big Pump', 'SP3': '1.50 L'},
    {'SP1': '523001', 'SP2': 'Leonie Still', 'SP3': '1.50 L'},
    {'SP1': '641301', 'SP2': 'Cola Mix', 'SP3': '1.50 L'}
]

class Tabelle(BoxLayout):
    def __init__(self, **kwargs):
        super(Tabelle, self).__init__(**kwargs)

    def insert_SP(self, data):
        for i in data:
            self.spalte1_SP = i['SP1']
            #print(self.spalte1_SP)
            self.spalte2_SP = i['SP2']
            self.spalte3_SP = i['SP3']

Builder.load_string('''
<Tabelle>:
    orientation: 'horizontal'
    spalte1_SP: 'spalte1'
    spalte2_SP: 'spalte2'
    spalte3_SP: 'spalte3'
    Label:
        id: Spalte1
        text: root.spalte1_SP
    Label:
        id: Spalte2
        text: root.spalte2_SP
    Label:
        id: Spalte3
        text: root.spalte3_SP

<RV>:
    viewclass: 'Tabelle'
    RecycleBoxLayout:
        default_size: None, dp(20)
        default_size_hint: 1, None
        size_hint_y: None
        height: self.minimum_height
        orientation: 'vertical'
''')

class RV(RecycleView):
    def __init__(self, **kwargs):
        super(RV, self).__init__(**kwargs)
        #self.data = []
        x = Tabelle()
        x.insert_SP(items)

class TestApp(App):
    def build(self):
        return RV()

if __name__ == '__main__':
    TestApp().run()

I expect to see the data from items in 3 columns, but they stay empty for some reason.

Answer 1

Based on the previous solution, here's a code whose interpretation is much easier. Additionally, one of the column is a checkbox.

Result:

Python file:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout

# data
items = [{'number': '510001', 'name': 'Big Pump', 'size': '1.50 L', 'in_stock': True},
         {'number': '523001', 'name': 'Leonie Still', 'size': '1.60 L', 'in_stock': False},
         {'number': '641301', 'name': 'Apple Mix', 'size': '1.30 L', 'in_stock': True},
         {'number': '681301', 'name': 'Orange Mix', 'size': '1.40 L', 'in_stock': True}
        ]


class MultiFieldLine(BoxLayout):
    # class layout defined in kv file
    pass


class AppGUI(GridLayout):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self.rv.data = [{'label_1': str(x['number']), 'label_2': str(x['name']), 'label_3': str(x['size']), 'checkbox_1': x['in_stock']} for x in items]


class ExploreRecycleViewMultipleFieldApp(App):
    def build(self):
        return AppGUI()


if __name__ == '__main__':
    ExploreRecycleViewMultipleFieldApp().run()

KV file:

<MultiFieldLine>:
    orientation: 'horizontal'
    label_1: ''
    label_2: ''
    label_3: ''
    checkbox_1: False
    Label:
        text: root.label_1
    Label:
        text: root.label_2
    Label:
        text: root.label_3
    CheckBox:
        active: root.checkbox_1
<AppGUI>: # inherit from GridLayout
    rv: rv_id
    cols:  1
    rows: 2
    GridLayout: # col titles
        cols: 4
        rows: 1
        size_hint_y: 0.04
        Label:
            text: 'Number'
        Label:
            text: 'Name'
        Label:
            text: 'Size'
        Label
            text: 'In stock'
    GridLayout: # data
        cols: 1
        rows: 1
        size_hint_y: 0.96
        RecycleView:
            id: rv_id
            viewclass: 'MultiFieldLine'
            RecycleBoxLayout:
                default_size: None, dp(20)
                default_size_hint: 1, None
                size_hint_y: None
                height: self.minimum_height
                orientation: 'vertical'

The version below adds row selection as well as a larger label width for the name column and a method in the gui class called each time a line is selected.:

Result:

Python file:

from kivy.app import App
from kivy.properties import BooleanProperty
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout

# data
from kivy.uix.recycleboxlayout import RecycleBoxLayout
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
from kivy.uix.recycleview.views import RecycleDataViewBehavior

items = [{'number': '510001', 'name': 'Big Pump', 'size': '1.50 L', 'in_stock': True},
         {'number': '523001', 'name': 'Leonie Still very, very,very long, long name', 'size': '1.60 L', 'in_stock': False},
         {'number': '641301', 'name': 'Apple Mix', 'size': '1.30 L', 'in_stock': True},
         {'number': '681301', 'name': 'Orange Mix', 'size': '1.40 L', 'in_stock': True}
        ]


class MultiFieldLine(RecycleDataViewBehavior, BoxLayout):
    ''' class layout defined in kv file '''
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)
    
    def refresh_view_attrs(self, rv, index, data):
        ''' Catch and handle the view changes '''
        self.rv = rv
        self.appGUI = rv.appGUI
        self.index = index
        
        return super(MultiFieldLine, self).refresh_view_attrs(
            rv, index, data)
    
    def on_touch_down(self, touch):
        ''' Add selection on touch down '''
        if super(MultiFieldLine, 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):
        # instance variable used in .kv file to change the selected item
        # color !
        self.selected = is_selected
  
        if is_selected:
            self.appGUI.outputSelectedData(rv.data[index])


class SelectableRecycleBoxLayout(FocusBehavior, LayoutSelectionBehavior,
                                 RecycleBoxLayout):
    ''' Adds selection and focus behaviour to the view. '''
    
    # required to authorise unselecting a selected item
    touch_deselect_last = BooleanProperty(True)


class AppGUI(GridLayout):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self.rv.data = [{'label_1': str(x['number']), 'label_2': str(x['name']), 'label_3': str(x['size']), 'checkbox_1': x['in_stock']} for x in items]

    def outputSelectedData(self, data):
    # method called when a line is selected
        print(data)

class ExploreRecycleViewMultipleFieldBoxLayoutApp(App):
    def build(self):
        return AppGUI()


if __name__ == '__main__':
    ExploreRecycleViewMultipleFieldBoxLayoutApp().run()

KV file:

<MultiFieldLine>: # inherit from RecycleDataViewBehavior and BoxLayout
    orientation: 'horizontal'
    label_1: ''
    label_2: ''
    label_3: ''
    checkbox_1: False
    # add selection background
    canvas.before:
        Color:
            rgba: (1, 0, 0, 1) if self.selected else (.0, 0.9, .1, .3)
        Rectangle:
            pos: self.pos
            size: self.size
        Color:
            rgba: (0, 0.9, .1, .3)
    Label:
        size_hint_x: 0.1
        text: root.label_1
    Label:
        size_hint_x: 0.7
        text: root.label_2
    Label:
        size_hint_x: 0.1
        text: root.label_3
    CheckBox:
        size_hint_x: 0.1
        active: root.checkbox_1
<AppGUI>: # inherit from GridLayout
    rv: rv_id
    cols:  1
    rows: 2
    GridLayout: # col titles
        cols: 4
        rows: 1
        size_hint_y: 0.04
        Label:
            size_hint_x: 0.1
            text: 'Number'
        Label:
            size_hint_x: 0.7
            text: 'Name'
        Label:
            size_hint_x: 0.1
            text: 'Size'
        Label
            size_hint_x: 0.1
            text: 'In stock'
    GridLayout: # data
        cols: 1
        rows: 1
        size_hint_y: 0.96
        RecycleView:
            id: rv_id
            appGUI: root
            viewclass: 'MultiFieldLine'
            SelectableRecycleBoxLayout:
                default_size: None, dp(20)
                default_size_hint: 1, None
                size_hint_y: None
                height: self.minimum_height
                orientation: 'vertical'

Answer 2

It is empty because data was not populated.

Solution

• Remove all codings in class Tabelle()
• Add pass into class Tabelle()
• Add the following into constructor, __init__() of class RV()

Snippets

self.data = [{'spalte1_SP': str(x['SP1']), 'spalte2_SP': str(x['SP2']), 'spalte3_SP': str(x['SP3'])} for x in items]

Kivy RecycleView » data

The view is generatad by processing the data, essentially a list of dicts, and uses these dicts to generate instances of the viewclass as required.

data

The data used by the current view adapter. This is a list of dicts whose keys map to the corresponding property names of the viewclass.

data is an AliasProperty that gets and sets the data used to generate the views.

Example

main.py

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.boxlayout import BoxLayout

items = [{'SP1': 'Artikelnummer', 'SP2': 'Name', 'SP3': 'Groesse'},
         {'SP1': '510001', 'SP2': 'Big Pump', 'SP3': '1.50 L'},
         {'SP1': '523001', 'SP2': 'Leonie Still', 'SP3': '1.50 L'},
         {'SP1': '641301', 'SP2': 'Cola Mix', 'SP3': '1.50 L'}
         ]


class Tabelle(BoxLayout):
    pass


Builder.load_string('''
<Tabelle>:
    orientation: 'horizontal'
    spalte1_SP: 'spalte1'
    spalte2_SP: 'spalte2'
    spalte3_SP: 'spalte3'
    Label:
        id: SP1
        text: root.spalte1_SP
    Label:
        id: SP2
        text: root.spalte2_SP
    Label:
        id: SP3
        text: root.spalte3_SP

<RV>:
    viewclass: 'Tabelle'
    RecycleBoxLayout:
        default_size: None, dp(20)
        default_size_hint: 1, None
        size_hint_y: None
        height: self.minimum_height
        orientation: 'vertical'
''')


class RV(RecycleView):
    def __init__(self, **kwargs):
        super(RV, self).__init__(**kwargs)
        self.data = [{'spalte1_SP': str(x['SP1']), 'spalte2_SP': str(x['SP2']), 'spalte3_SP': str(x['SP3'])} for x in items]


class TestApp(App):
    def build(self):
        return RV()


if __name__ == '__main__':
    TestApp().run()

Output