White Background during SlideTransition

[todestoast]

The Problem

As seen above during the transitions the background suddenly becomes white.

What have I tried?

• set background color for both Screens
• set clearcolor for ScreenManager
• set Background Color for ScreenManager
• also tested with native kivy elements (no KivyMD) - this has no effect

My Code md.kv:

#:import C kivy.utils.get_color_from_hex
#: import ScreenManager kivy.uix.screenmanager.ScreenManager
<MainWindow>:
    name: "main"
    canvas:
        Color:
            rgba: C('#18294a')
        Rectangle:
            pos: self.pos
            size: self.size

    FloatLayout:
        Label:
            text:"Connect to this computer"
            font_size: 20
            color: C('#ffffff')
            pos_hint: {"x":.08, "y":.3}
            size_hint: 0.35, 0.15

        Label:
            text:"Connect to another computer"
            font_size: 20
            color: C('#ffffff')
            pos_hint: {"x":.58, "y":.3}
            size_hint: 0.35, 0.15

       MDIconButton:
            ripple_scale: 0
            #md_bg_color: app.theme_cls.primary_color
            theme_text_color: "Custom"
            text_color: C('#ffffff') 
            icon: "arrow-down-bold"
            user_font_size:"200sp"
            #md_bg_color: C('#ffffff') 
            pos_hint:{"x":0.1,"y":0.4}
            size_hint: .3, .3
            on_release:
                root.manager.transition.direction = "down"
                root.connectTo()

                
        MDIconButton:
            ripple_scale: 0
            #md_bg_color: app.theme_cls.primary_color
            theme_text_color: "Custom"
            text_color: C('#ffffff') 
            icon: "arrow-up-bold"
            user_font_size:"200sp"
            #md_bg_color: C('#ffffff') 
            pos_hint:{"x":0.6,"y":0.4}
            size_hint: .3, .3
            on_release:
                root.manager.transition.direction = "up"
                root.connectTo()

<ConnectToWindow>:
    name: "connectTo"
    canvas:
        Color:
            rgba: C('#18294a')
        Rectangle:
            pos: self.pos
            size: self.size

ScreenManager:
    clearcolor: C('#18294a')
    canvas:
        Color:
            rgba: C('#18294a')
        Rectangle:
            size: self.size
            pos: self.pos
    id: sm

main.py:

sm = ScreenManager(transition=SlideTransition())

class MainWindow(Screen):
    def connectTo(self):
        sm.current = "connectTo"


    def establishConnect(self):
        sm.current = "main"

class MyMainApp(MDApp):
    def build(self):
        kv = Builder.load_file("md.kv")
        screens = [MainWindow(name="main"),ConnectToWindow(name="connectTo")]
        for screen in screens:
            sm.add_widget(screen)

        sm.current = "main"
        return sm



if __name__ == "__main__":
    MyMainApp().run()

[neo-mashiro]

I have the same problem, but I guess it is supposed to work like this, the slide transition is not seamless.

You can use the CardTransition, which is seamless, but I found that WipeTransition is more elegant.

[andrzejs]

Hi todestoast, Try this:

#:import C kivy.utils.get_color_from_hex
#:import ScreenManager kivy.uix.screenmanager.ScreenManager

  <MainWindow>:
      name: "main"
      FloatLayout:
          canvas:
                  Color:
                      rgba: C('#18294a')
                  Rectangle:
                      pos: self.pos
                      size: self.size

.....

Block canvas should be after FloatLayout:

Andrzej

[Serelue]

I solved it by writing the code like this

from kivy.core.window import Window

Window.clearcolor = (1, 0, 0, 1)

https://kivy.org/doc/stable/api-kivy.core.window.html#kivy.core.window.WindowBase.clearcolor

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