在Kivy中调整大小会在小部件之间留出空白

Question

I've created a basic GUI, to test scrollview and get a platform to build on further. When resizing my window, there comes black space above my widgets, and there is also a lot of black space between them.

I've tried with "anchor" and "pos" but can't get the widgets to stay in the top of the window.

class GUI(App):
    def build(self):
        root = FloatLayout(size_hint=(1, None), size=(Window.width, Window.height))
        sidepanel = BoxLayout(orientation="vertical", size_hint=(None, 1), pos_hint={"x": 0.0, "y": 0.0})
        scroll = ScrollView(pos_hint={"x": 0.2, "y": 0.0})
        layout = BoxLayout(orientation="vertical", spacing=10, size_hint_y=None)

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

        for i in range(50):
            btn = Button(text=str(i), size_hint_y=None, height=30)
            layout.add_widget(btn)


        sidepanel.add_widget(Button(text="Import Photos", size_hint=(1,0.2)))
        sidepanel.add_widget(Button(text="Create Report", size_hint=(1,0.2)))
        sidepanel.add_widget(Button(text="Save?", size_hint=(1,0.2)))
        sidepanel.add_widget(Button(text="Button 4", size_hint=(1,0.2)))


        scroll.add_widget(layout)


        root.add_widget(sidepanel)
        root.add_widget(scroll)

        return root

I would expect the sidepanel to stay the same size, and the scrollview containing "layout" to resize with the window. And all widgets should stay in the top.

Standard window

Resized window

Answer 1

Your issue is stemming from your size specifications in your 'root' floatlayout. Try using:

root = FloatLayout()

where you don't specify any size instructions. It will know how to resize itself properly automatically with the window. Generally you want to avoid using both size_hint and size together on the same widget. Same goes for pos_hint and pos .