how to maximize scrollbar in Kivy python?

问题:

I am using multiTab in kivy. How to enlarge the scrollbar so that scrollbar can be moved(up_down) by mouse. I am using BoxLayout and RecycleView. The code below was working with gridLayout, but not in BoxLayout:

layout.bind(minimum_height=layout.setter('height'))

回答1:

Here is an example of how to extend ScrollView to also get a dragable slider.

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.lang import Builder
from kivy.uix.label import Label

Builder.load_string("""
<ScrollSlider>:
    ScrollView:
        id: scrlvw
        bar_width: 0
        GridLayout:
            id: grid
            size_hint_y:None
            cols:1
            height: self.minimum_height
            scroll_y: slider.value
            on_touch_move: slider.value = self.scroll_y
    Slider:
        size_hint_x: None
        width: root.width*0.2
        id: slider
        min: 0
        max: 1
        orientation: 'vertical'
        value: scrlvw.scroll_y
        on_value: scrlvw.scroll_y = self.value

""")


class ScrollSlider(BoxLayout):

    def custom_add(self, widget):
        self.ids.grid.add_widget(widget)

class MyApp(App):


    def build(self):
        scrollslider = ScrollSlider()
        for i in range(1, 100):
            scrollslider.custom_add(Label(text=str(i), height=100, size_hint_y=None))
        return scrollslider

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

You need to use the custom_add to add widgets in the ScrollSlider or add them to the GridLayout in kivy.

I took some inspiration from the link @Edvardas Dlugauskas provided.

The code you provided does not work with BoxLayout because BoxLayout just takes the size of its parent. To be able to scroll you need to add sth into ScrollView which is larger than the ScrollView itself.